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/*
* This file is part of FastClasspathScanner.
*
* Author: Luke Hutchison
*
* Hosted at: https://github.com/lukehutch/fast-classpath-scanner
*
* --
*
* The MIT License (MIT)
*
* Copyright (c) 2016 Luke Hutchison
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
* documentation files (the "Software"), to deal in the Software without restriction, including without
* limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or substantial
* portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
* LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO
* EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
* AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
* OR OTHER DEALINGS IN THE SOFTWARE.
*/
package io.github.lukehutch.fastclasspathscanner;
import java.io.File;
import java.lang.annotation.Annotation;
import java.lang.annotation.RetentionPolicy;
import java.net.URL;
import java.util.List;
import java.util.Set;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import io.github.lukehutch.fastclasspathscanner.classloaderhandler.ClassLoaderHandler;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.ClassAnnotationMatchProcessor;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.ClassMatchProcessor;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.FieldAnnotationMatchProcessor;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.FileMatchContentsProcessor;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.FileMatchContentsProcessorWithContext;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.FileMatchProcessor;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.FileMatchProcessorWithContext;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.FilenameMatchProcessor;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.ImplementingClassMatchProcessor;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.MethodAnnotationMatchProcessor;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.StaticFinalFieldMatchProcessor;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.SubclassMatchProcessor;
import io.github.lukehutch.fastclasspathscanner.matchprocessor.SubinterfaceMatchProcessor;
import io.github.lukehutch.fastclasspathscanner.scanner.ClassLoaderFinder;
import io.github.lukehutch.fastclasspathscanner.scanner.FailureHandler;
import io.github.lukehutch.fastclasspathscanner.scanner.ScanResult;
import io.github.lukehutch.fastclasspathscanner.scanner.ScanResultProcessor;
import io.github.lukehutch.fastclasspathscanner.scanner.ScanSpec;
import io.github.lukehutch.fastclasspathscanner.scanner.Scanner;
import io.github.lukehutch.fastclasspathscanner.utils.AutoCloseableExecutorService;
import io.github.lukehutch.fastclasspathscanner.utils.JarUtils;
import io.github.lukehutch.fastclasspathscanner.utils.LogNode;
import io.github.lukehutch.fastclasspathscanner.utils.VersionFinder;
/**
* Uber-fast, ultra-lightweight Java classpath scanner. Scans the classpath by parsing the classfile binary format
* directly rather than by using reflection. (Reflection causes the classloader to load each class, which can take
* an order of magnitude more time than parsing the classfile directly.)
*
*
* Documentation:
*
*
* https://github.com/lukehutch/fast-classpath-scanner/wiki
*/
public class FastClasspathScanner {
/**
* The scanning specification (whitelisted and blacklisted packages, etc.), as passed into the constructor.
*/
private final String[] scanSpecArgs;
/** The scanning specification, parsed. */
private ScanSpec scanSpec;
/** The unique classpath elements. */
private List classpathElts;
/** The unique classpath element URLs. */
private List classpathEltURLs;
/** The FastClasspathScanner version. */
private static String version;
/**
* The default number of worker threads to use while scanning. This number gave the best results on a relatively
* modern laptop with SSD, while scanning a large classpath.
*/
private static final int DEFAULT_NUM_WORKER_THREADS = 6;
/** If non-null, log while scanning */
private LogNode log;
// -------------------------------------------------------------------------------------------------------------
/**
* Construct a FastClasspathScanner instance. You can pass a scanning specification to the constructor to
* describe what should be scanned -- see the docs for info:
*
*
* https://github.com/lukehutch/fast-classpath-scanner/wiki/2.-Constructor
*
*
* The scanSpec, if non-empty, prevents irrelevant classpath entries from being unecessarily scanned, which can
* be time-consuming.
*
*
* Note that calling the constructor does not start the scan, you must separately call .scan() to perform the
* actual scan.
*
* @param scanSpec
* The constructor accepts a list of whitelisted package prefixes / jar names to scan, as well as
* blacklisted packages/jars not to scan, where blacklisted entries are prefixed with the '-'
* character. See https://github.com/lukehutch/fast-classpath-scanner/wiki/2.-Constructor for info.
*/
public FastClasspathScanner(final String... scanSpec) {
this.scanSpecArgs = scanSpec;
}
/**
* Get the version number of FastClasspathScanner.
*
* @return the FastClasspathScanner version, or "unknown" if it could not be determined.
*/
public static final String getVersion() {
if (version == null) {
version = VersionFinder.getVersion();
}
return version;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Lazy initializer for scanSpec. (This is lazy so that you have a chance to call verbose() before the ScanSpec
* constructor tries to log something.)
*/
private synchronized ScanSpec getScanSpec() {
if (scanSpec == null) {
scanSpec = new ScanSpec(scanSpecArgs, log == null ? null : log.log("Parsing scan spec"));
}
return scanSpec;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Switches on verbose mode for debugging purposes if verbose == true. Call immediately after calling the
* constructor if you want full log output. Prints debug info to System.err.
*
* @param verbose
* Whether or not to give verbose output.
* @return this (for method chaining).
*/
public FastClasspathScanner verbose(final boolean verbose) {
if (verbose) {
if (log == null) {
log = new LogNode();
}
} else {
log = null;
}
return this;
}
/**
* Switches on verbose mode for debugging purposes. Call immediately after calling the constructor if you want
* full log output. Prints debug info to System.err.
*
* @return this (for method chaining).
*/
public FastClasspathScanner verbose() {
verbose(true);
return this;
}
/**
* If ignoreFieldVisibility is true, causes FastClasspathScanner to ignore field visibility, enabling it to see
* private, package-private and protected fields. This affects finding classes with fields of a given type, as
* well as matching static final fields with constant initializers, and saving FieldInfo for the class. If
* false, fields must be public to be indexed/matched.
*
* @param ignoreFieldVisibility
* Whether or not to ignore the field visibility modifier.
* @return this (for method chaining).
*/
public FastClasspathScanner ignoreFieldVisibility(final boolean ignoreFieldVisibility) {
getScanSpec().ignoreFieldVisibility = ignoreFieldVisibility;
return this;
}
/**
* This method causes FastClasspathScanner to ignore field visibility, enabling it to see private,
* package-private and protected fields. This affects finding classes with fields of a given type, as well as
* matching static final fields with constant initializers, and saving FieldInfo for the class. If false, fields
* must be public to be indexed/matched.
*
* @return this (for method chaining).
*/
public FastClasspathScanner ignoreFieldVisibility() {
ignoreFieldVisibility(true);
return this;
}
/**
* If ignoreMethodVisibility is true, causes FastClasspathScanner to ignore method visibility, enabling it to
* see private, package-private and protected methods. This affects finding classes that have methods with a
* given annotation, and also the saving of MethodInfo for the class. If false, methods must be public for the
* containing classes to be indexed/matched.
*
* @param ignoreMethodVisibility
* Whether or not to ignore the method visibility modifier.
* @return this (for method chaining).
*/
public FastClasspathScanner ignoreMethodVisibility(final boolean ignoreMethodVisibility) {
getScanSpec().ignoreMethodVisibility = ignoreMethodVisibility;
return this;
}
/**
* This method causes FastClasspathScanner to ignore method visibility, enabling it to see private,
* package-private and protected methods. This affects finding classes that have methods with a given
* annotation, and also the saving of MethodInfo for the class. If false, methods must be public for the
* containing classes to be indexed/matched.
*
* @return this (for method chaining).
*/
public FastClasspathScanner ignoreMethodVisibility() {
ignoreMethodVisibility(true);
return this;
}
/**
* If enableMethodAnnotationIndexing is true, enables method annotation indexing, which allows you to call
* ScanResult#getNamesOfClassesWithMethodAnnotation(annotation). (If you add a method annotation match
* processor, this method is called for you.) Method annotation indexing is disabled by default, because it is
* expensive in terms of time, and it is not needed for most uses of FastClasspathScanner.
*
* @param enableMethodAnnotationIndexing
* Whether or not to enable method annotation indexing.
* @return this (for method chaining).
*/
public FastClasspathScanner enableMethodAnnotationIndexing(final boolean enableMethodAnnotationIndexing) {
getScanSpec().enableMethodAnnotationIndexing = enableMethodAnnotationIndexing;
return this;
}
/**
* Enables method annotation indexing, which allows you to call
* ScanResult#getNamesOfClassesWithMethodAnnotation(annotation). (If you add a method annotation match
* processor, this method is called for you.) Method annotation indexing is disabled by default, because it is
* expensive in terms of time, and it is not needed for most uses of FastClasspathScanner.
*
* @return this (for method chaining).
*/
public FastClasspathScanner enableMethodAnnotationIndexing() {
enableMethodAnnotationIndexing(true);
return this;
}
/**
* If enableFieldAnnotationIndexing is true, enables field annotation indexing, which allows you to call
* ScanResult#getNamesOfClassesWithFieldAnnotation(annotation). (If you add a method annotation match processor,
* this method is called for you.) Method annotation indexing is disabled by default, because it is expensive in
* terms of time, and it is not needed for most uses of FastClasspathScanner.
*
* @param enableFieldAnnotationIndexing
* Whether to enable field annotation indexing.
* @return this (for method chaining).
*/
public FastClasspathScanner enableFieldAnnotationIndexing(final boolean enableFieldAnnotationIndexing) {
getScanSpec().enableFieldAnnotationIndexing = enableFieldAnnotationIndexing;
return this;
}
/**
* Enables field annotation indexing, which allows you to call
* ScanResult#getNamesOfClassesWithFieldAnnotation(annotation). (If you add a method annotation match processor,
* this method is called for you.) Method annotation indexing is disabled by default, because it is expensive in
* terms of time, and it is not needed for most uses of FastClasspathScanner.
*
* @return this (for method chaining).
*/
public FastClasspathScanner enableFieldAnnotationIndexing() {
enableFieldAnnotationIndexing(true);
return this;
}
/**
* If enableFieldInfo is true, enables the saving of field info during the scan. This information can be
* obtained using ClassInfo#getFieldInfo(). By default, field info is not saved, because enabling this option
* will cause the scan to take somewhat longer and potentially consume a lot more memory.
*
* @param enableFieldInfo
* If true, save field info while scanning. (Default false.)
* @return this (for method chaining).
*/
public FastClasspathScanner enableFieldInfo(final boolean enableFieldInfo) {
getScanSpec().enableFieldInfo = enableFieldInfo;
return this;
}
/**
* Enables the saving of field info during the scan. This information can be obtained using
* ClassInfo#getFieldInfo(). By default, field info is not saved, because enabling this option will cause the
* scan to take somewhat longer and potentially consume a lot more memory.
*
* @return this (for method chaining).
*/
public FastClasspathScanner enableFieldInfo() {
return enableFieldInfo(true);
}
/**
* If enableMethodInfo is true, enables the saving of method info during the scan. This information can be
* obtained using ClassInfo#getMethodInfo(). By default, method info is not saved, because enabling this option
* will cause the scan to take somewhat longer and potentially consume a lot more memory.
*
* @param enableMethodInfo
* If true, save method info while scanning. (Default false.)
* @return this (for method chaining).
*/
public FastClasspathScanner enableMethodInfo(final boolean enableMethodInfo) {
getScanSpec().enableMethodInfo = enableMethodInfo;
return this;
}
/**
* Enables the saving of method info during the scan. This information can be obtained using
* ClassInfo#getMethodInfo(). By default, method info is not saved, because enabling this option will cause the
* scan to take somewhat longer and potentially consume a lot more memory.
*
* @return this (for method chaining).
*/
public FastClasspathScanner enableMethodInfo() {
return enableMethodInfo(true);
}
/**
* Allows you to scan default packages (with package name "") without scanning sub-packages unless they are
* whitelisted. This is needed because if you add the package name "" to the whitelist, that package and all
* sub-packages will be scanned, which means everything will be scanned. This method makes it possible to
* whitelist just the toplevel (default) package but not its sub-packages.
*
* @param alwaysScanClasspathElementRoot
* If true, always scan the classpath element root, regardless of the whitelist or blacklist.
* @return this (for method chaining).
*/
public FastClasspathScanner alwaysScanClasspathElementRoot(final boolean alwaysScanClasspathElementRoot) {
if (alwaysScanClasspathElementRoot) {
getScanSpec().whitelistedPathsNonRecursive.add("");
getScanSpec().whitelistedPathsNonRecursive.add("/");
} else {
getScanSpec().whitelistedPathsNonRecursive.remove("");
getScanSpec().whitelistedPathsNonRecursive.remove("/");
}
return this;
}
/**
* Allows you to scan default packages (with package name "") without scanning sub-packages unless they are
* whitelisted. This is needed because if you add the package name "" to the whitelist, that package and all
* sub-packages will be scanned, which means everything will be scanned. This method makes it possible to
* whitelist just the toplevel (default) package but not its sub-packages.
*
* @return this (for method chaining).
*/
public FastClasspathScanner alwaysScanClasspathElementRoot() {
return alwaysScanClasspathElementRoot(true);
}
/**
* If strictWhitelist is true, switches FastClasspathScanner to strict mode, which disallows searching/matching
* based on blacklisted classes, and removes "external" classes from result lists returned by ScanSpec#get...()
* methods. (External classes are classes outside of whitelisted packages that are directly referred to by
* classes within whitelisted packages as a superclass, implemented interface or annotation.)
*
*
* See the following for info on external classes, and strict mode vs. non-strict mode:
*
*
* https://github.com/lukehutch/fast-classpath-scanner/wiki/2.-Constructor#external-classes
*
* @param strictWhitelist
* Whether or not to switch to strict mode.
* @return this (for method chaining).
*/
public FastClasspathScanner strictWhitelist(final boolean strictWhitelist) {
getScanSpec().strictWhitelist = strictWhitelist;
return this;
}
/**
* Switches FastClasspathScanner to strict mode, which disallows searching/matching based on blacklisted
* classes, and removes "external" classes from result lists returned by ScanSpec#get...() methods. (External
* classes are classes outside of whitelisted packages that are directly referred to by classes within
* whitelisted packages as a superclass, implemented interface or annotation.)
*
*
* See the following for info on external classes, and strict mode vs. non-strict mode:
*
*
* https://github.com/lukehutch/fast-classpath-scanner/wiki/2.-Constructor#external-classes
*
* @return this (for method chaining).
*/
public FastClasspathScanner strictWhitelist() {
strictWhitelist(true);
return this;
}
/**
* If initializeLoadedClasses is true, classes loaded with Class.forName() are initialized before passing class
* references to MatchProcessors. If false (the default), matched classes are loaded but not initialized before
* passing class references to MatchProcessors (meaning classes are instead initialized lazily on first usage of
* the class).
*
* @param initializeLoadedClasses
* Whether or not to initialize classes before passing class references to MatchProcessors. (The
* default value is false.)
* @return this (for method chaining).
*/
public FastClasspathScanner initializeLoadedClasses(final boolean initializeLoadedClasses) {
getScanSpec().initializeLoadedClasses = initializeLoadedClasses;
return this;
}
/**
* If true (the default), nested jarfiles (jarfiles within jarfiles, which have to be extracted during scanning
* in order to be read) are removed from their temporary directory after the scan has completed. If false,
* temporary files are only removed on JVM exit.
*
*
* This method should be called if you need to access nested jarfiles (e.g. from a Spring classpath) after
* scanning has completed. In particular, if you use ClasspathUtils.getClasspathResourceURL() in a
* FileMatchProcessor and you need to use the returned URLs after scanning has completed, then you should call
* FastClasspathScanner#removeTemporaryFilesAfterScan(false) before calling scan().
*
* @param removeTemporaryFilesAfterScan
* Whether or not to remove temporary files after scanning. (The default value is true.)
* @return this (for method chaining).
*/
public FastClasspathScanner removeTemporaryFilesAfterScan(final boolean removeTemporaryFilesAfterScan) {
getScanSpec().removeTemporaryFilesAfterScan = removeTemporaryFilesAfterScan;
return this;
}
/**
* Disable recursive scanning. Causes only toplevel entries within each whitelisted package to be scanned, i.e.
* sub-packages of whitelisted packages will not be scanned. If no whitelisted packages were provided to the
* constructor, then only the toplevel directory within each classpath element will be scanned.
*
* @return this (for method chaining).
*/
public FastClasspathScanner disableRecursiveScanning() {
return disableRecursiveScanning(true);
}
/**
* If true, disable recursive scanning. Causes only toplevel entries within each whitelisted package to be
* scanned, i.e. sub-packages of whitelisted packages will not be scanned. If no whitelisted packages were
* provided to the constructor, then only the toplevel directory within each classpath element will be scanned.
* If false (the default), whitelisted paths and their subdirectories will be scanned.
*
* @param disableRecursiveScanning
* Whether or not to disable recursive scanning. (The default value is false.)
* @return this (for method chaining).
*/
public FastClasspathScanner disableRecursiveScanning(final boolean disableRecursiveScanning) {
getScanSpec().disableRecursiveScanning = disableRecursiveScanning;
return this;
}
/**
* Manually strip the self extracting executable header from zipfiles (i.e. anything before the magic marker
* "PK", e.g. a Bash script added by Spring-Boot). Slightly increases scanning time, since zipfiles have to be
* opened twice (once as a byte stream, to check if there is an SFX header, then once as a ZipFile, for
* decompression).
*
* Should only be needed in rare cases, where you are dealing with jarfiles with prepended (ZipSFX) headers,
* where your JVM does not already automatically skip forward to the first "PK" marker (Oracle JVM on Linux does
* this automatically).
*
* @return this (for method chaining).
*/
public FastClasspathScanner stripZipSFXHeaders() {
getScanSpec().stripSFXHeader = true;
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Register an extra ClassLoaderHandler. Needed if FastClasspathScanner doesn't know how to extract classpath
* entries from your runtime environment's ClassLoader. See:
*
*
* https://github.com/lukehutch/fast-classpath-scanner/wiki/4.-Working-with-nonstandard-ClassLoaders
*
* @param classLoaderHandlerClass
* The ClassLoaderHandler class to register.
* @return this (for method chaining).
*/
public FastClasspathScanner registerClassLoaderHandler(
final Class classLoaderHandlerClass) {
getScanSpec().registerClassLoaderHandler(classLoaderHandlerClass);
return this;
}
/**
* Override the automatically-detected classpath with a custom path, with path elements separated by
* File.pathSeparatorChar. Causes system ClassLoaders and the java.class.path system property to be ignored.
*
*
* If this method is called, nothing but the provided classpath will be scanned, i.e. this causes ClassLoaders
* to be ignored, as well as the java.class.path system property.
*
* @param overrideClasspath
* The custom classpath to use for scanning, with path elements separated by File.pathSeparatorChar.
* @return this (for method chaining).
*/
public FastClasspathScanner overrideClasspath(final String overrideClasspath) {
getScanSpec().overrideClasspath(overrideClasspath);
return this;
}
/**
* Override the automatically-detected classpath with a custom path. Causes system ClassLoaders and the
* java.class.path system property to be ignored. Works for Iterables of any type whose toString() method
* resolves to a classpath element string, e.g. String, File or Path.
*
*
* If this method is called, nothing but the provided classpath will be scanned, i.e. this causes ClassLoaders
* to be ignored, as well as the java.class.path system property.
*
* @param overrideClasspathElements
* The custom classpath to use for scanning, with path elements separated by File.pathSeparatorChar.
* @return this (for method chaining).
*/
public FastClasspathScanner overrideClasspath(final Iterable overrideClasspathElements) {
final String overrideClasspath = JarUtils.pathElementsToPathStr(overrideClasspathElements);
if (overrideClasspath.isEmpty()) {
throw new IllegalArgumentException("Can't override classpath with an empty path");
}
overrideClasspath(overrideClasspath);
return this;
}
/**
* Override the automatically-detected classpath with a custom path. Causes system ClassLoaders and the
* java.class.path system property to be ignored. Works for arrays of any member type whose toString() method
* resolves to a classpath element string, e.g. String, File or Path.
*
* @param overrideClasspathElements
* The custom classpath to use for scanning, with path elements separated by File.pathSeparatorChar.
* @return this (for method chaining).
*/
public FastClasspathScanner overrideClasspath(final Object... overrideClasspathElements) {
final String overrideClasspath = JarUtils.pathElementsToPathStr(overrideClasspathElements);
if (overrideClasspath.isEmpty()) {
throw new IllegalArgumentException("Can't override classpath with an empty path");
}
overrideClasspath(overrideClasspath);
return this;
}
/**
* Add a classpath element filter. The includeClasspathElement method should return true if the path string
* passed to it is a path you want to scan.
*/
@FunctionalInterface
public interface ClasspathElementFilter {
/**
* @param classpathElementString
* The path string of a classpath element, normalized so that the path separator is '/'. This
* will usually be a file path, but could be a URL, or it could be a path for a nested jar, where
* the paths are separated using '!', in Java convention. "jar:" and/or "file:" will have been
* stripped from the beginning, if they were present in the classpath.
* @return true if the path string passed is a path you want to scan.
*/
public boolean includeClasspathElement(String classpathElementString);
}
/**
* Add a classpath element filter. The provided ClasspathElementFilter should return true if the path string
* passed to it is a path you want to scan.
*
* @param classpathElementFilter
* The filter function to use. This function should return true if the classpath element path should
* be scanned, and false if not.
* @return this (for method chaining).
*/
public FastClasspathScanner filterClasspathElements(final ClasspathElementFilter classpathElementFilter) {
getScanSpec().filterClasspathElements(classpathElementFilter);
return this;
}
/**
* Add a ClassLoader to the list of ClassLoaders to scan.
*
*
* This call is ignored if overrideClasspath() is also called, or if this method is called before
* overrideClassLoaders().
*
*
* This call is ignored if overrideClasspath() is called.
*
* @param classLoader
* The additional ClassLoader to scan.
* @return this (for method chaining).
*/
public FastClasspathScanner addClassLoader(final ClassLoader classLoader) {
getScanSpec().addClassLoader(classLoader);
return this;
}
/**
* Completely override (and ignore) system ClassLoaders and the java.class.path system property.
*
*
* This call is ignored if overrideClasspath() is called.
*
* @param overrideClassLoaders
* The ClassLoaders to scan instead of the automatically-detected ClassLoaders.
* @return this (for method chaining).
*/
public FastClasspathScanner overrideClassLoaders(final ClassLoader... overrideClassLoaders) {
getScanSpec().overrideClassLoaders(overrideClassLoaders);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Ignore parent classloaders (i.e. only obtain paths to scan from classloader(s), do not also fetch paths from
* parent classloader(s)).
*
*
* This call is ignored if overrideClasspath() is called.
*
* @param ignoreParentClassLoaders
* If true, do not fetch paths from parent classloaders.
* @return this (for method chaining).
*/
public FastClasspathScanner ignoreParentClassLoaders(final boolean ignoreParentClassLoaders) {
getScanSpec().ignoreParentClassLoaders = ignoreParentClassLoaders;
return this;
}
/**
* Ignore parent classloaders (i.e. only obtain paths to scan from classloader(s), do not also fetch paths from
* parent classloader(s)).
*
*
* This call is ignored if overrideClasspath() is called.
*
* @return this (for method chaining).
*/
public FastClasspathScanner ignoreParentClassLoaders() {
getScanSpec().ignoreParentClassLoaders = true;
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Causes exceptions thrown inside MatchProcessors to not be re-thrown, wrapped in a MatchProcessorException, at
* the end of a synchronous scan. Instead, any thrown exceptions can be fetched using
* ScanResult.getMatchProcessorExceptions().
*
* @return this (for method chaining).
*/
public FastClasspathScanner suppressMatchProcessorExceptions() {
suppressMatchProcessorExceptions(true);
return this;
}
/**
* If suppressMatchProcessorExceptions is true, exceptions thrown inside MatchProcessors are not re-thrown
* wrapped in a MatchProcessorException at the end of a synchronous scan, and any thrown exceptions can be
* fetched using ScanResult.getMatchProcessorExceptions(). If suppressMatchProcessorExceptions is false, at the
* end of a synchronous scan, if ScanResult.getMatchProcessorExceptions() returns a non-empty list,
* MatchProcessorException is thrown to the caller.
*
* @param suppressMatchProcessorExceptions
* Whether to suppress MatchProcessorExceptions.
* @return this (for method chaining).
*/
public FastClasspathScanner suppressMatchProcessorExceptions(final boolean suppressMatchProcessorExceptions) {
getScanSpec().suppressMatchProcessorExceptions = suppressMatchProcessorExceptions;
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Find the classloader or classloaders most likely to represent the order that classloaders are used to resolve
* classes in the current context. Uses the technique described by Vladimir
* Roubtsov.
*
*
* Generally this will return exactly one ClassLoader, but if it returns more than one, the classloaders are
* listed in the order they should be called in until one of them is able to load the named class. If you can
* call only one ClassLoader, use the first element of the list.
*
*
* If you have overridden the ClassLoader(s), then the override ClassLoader(s) will be returned instead.
*
* @return A list of one or more ClassLoaders, out of the system ClassLoader, the current classloader, or the
* context classloader (or the override ClassLoaders, if ClassLoaders have been overridden).
*/
public ClassLoader[] findBestClassLoader() {
return ClassLoaderFinder.findEnvClassLoaders(getScanSpec(), log).classLoaders;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the provided ClassMatchProcessor for all standard classes, interfaces and annotations found in
* whitelisted packages on the classpath.
*
* @param classMatchProcessor
* the ClassMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchAllClasses(final ClassMatchProcessor classMatchProcessor) {
getScanSpec().matchAllClasses(classMatchProcessor);
return this;
}
/**
* Calls the provided ClassMatchProcessor for all standard classes (i.e. non-interface, non-annotation classes)
* found in whitelisted packages on the classpath.
*
* @param standardClassMatchProcessor
* the ClassMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchAllStandardClasses(final ClassMatchProcessor standardClassMatchProcessor) {
getScanSpec().matchAllStandardClasses(standardClassMatchProcessor);
return this;
}
/**
* Calls the provided ClassMatchProcessor for all interface classes (interface definitions) found in whitelisted
* packages on the classpath.
*
* @param interfaceClassMatchProcessor
* the ClassMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchAllInterfaceClasses(final ClassMatchProcessor interfaceClassMatchProcessor) {
getScanSpec().matchAllInterfaceClasses(interfaceClassMatchProcessor);
return this;
}
/**
* Calls the provided ClassMatchProcessor for all annotation classes (annotation definitions) found in
* whitelisted packages on the classpath.
*
* @param annotationClassMatchProcessor
* the ClassMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchAllAnnotationClasses(final ClassMatchProcessor annotationClassMatchProcessor) {
getScanSpec().matchAllAnnotationClasses(annotationClassMatchProcessor);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the provided SubclassMatchProcessor if classes are found on the classpath that extend the specified
* superclass.
*
* @param superclass
* The superclass to match (i.e. the class that subclasses need to extend to match).
* @param subclassMatchProcessor
* the SubclassMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchSubclassesOf(final Class superclass,
final SubclassMatchProcessor subclassMatchProcessor) {
getScanSpec().matchSubclassesOf(superclass, subclassMatchProcessor);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the provided SubinterfaceMatchProcessor if an interface that extends a given superinterface is found on
* the classpath.
*
* @param superinterface
* The superinterface to match (i.e. the interface that subinterfaces need to extend to match).
* @param subinterfaceMatchProcessor
* the SubinterfaceMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchSubinterfacesOf(final Class superinterface,
final SubinterfaceMatchProcessor subinterfaceMatchProcessor) {
getScanSpec().matchSubinterfacesOf(superinterface, subinterfaceMatchProcessor);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the provided InterfaceMatchProcessor for classes on the classpath that implement the specified
* interface or a subinterface, or whose superclasses implement the specified interface or a sub-interface.
*
* @param implementedInterface
* The interface that classes need to implement.
* @param interfaceMatchProcessor
* the ClassMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchClassesImplementing(final Class implementedInterface,
final ImplementingClassMatchProcessor interfaceMatchProcessor) {
getScanSpec().matchClassesImplementing(implementedInterface, interfaceMatchProcessor);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the provided ClassAnnotationMatchProcessor if classes are found on the classpath that have the
* specified annotation.
*
* @param annotation
* The class annotation to match.
* @param classAnnotationMatchProcessor
* the ClassAnnotationMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchClassesWithAnnotation(final Class annotation,
final ClassAnnotationMatchProcessor classAnnotationMatchProcessor) {
getScanSpec().matchClassesWithAnnotation(annotation, classAnnotationMatchProcessor);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the provided MethodAnnotationMatchProcessor if classes are found on the classpath that have one or more
* methods with the specified annotation.
*
*
* Calls enableMethodAnnotationIndexing() for you.
*
* @param annotation
* The method annotation to match.
* @param methodAnnotationMatchProcessor
* the MethodAnnotationMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchClassesWithMethodAnnotation(final Class annotation,
final MethodAnnotationMatchProcessor methodAnnotationMatchProcessor) {
enableMethodAnnotationIndexing();
getScanSpec().matchClassesWithMethodAnnotation(annotation, methodAnnotationMatchProcessor);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the provided FieldAnnotationMatchProcessor if classes are found on the classpath that have one or more
* fields with the specified annotation.
*
*
* Calls enableFieldAnnotationIndexing() for you.
*
* @param annotation
* The field annotation to match.
* @param fieldAnnotationMatchProcessor
* the FieldAnnotationMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchClassesWithFieldAnnotation(final Class annotation,
final FieldAnnotationMatchProcessor fieldAnnotationMatchProcessor) {
enableFieldAnnotationIndexing();
getScanSpec().matchClassesWithFieldAnnotation(annotation, fieldAnnotationMatchProcessor);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Set annotation visibility (to match the annotation retention policy).
*
* @param annotationVisibility
* The annotation visibility: RetentionPolicy.RUNTIME matches only runtime-visible annotations. The
* default value, RetentionPolicy.CLASS, matches all annotations (both runtime-visible and
* runtime-invisible). RetentionPolicy.SOURCE will cause an IllegalArgumentException to be thrown,
* since SOURCE-annotated annotations are not retained in classfiles.
* @return this (for method chaining).
*/
public FastClasspathScanner setAnnotationVisibility(final RetentionPolicy annotationVisibility) {
if (annotationVisibility == RetentionPolicy.SOURCE) {
throw new IllegalArgumentException("RetentionPolicy.SOURCE annotations are not retained in classfiles");
}
getScanSpec().annotationVisibility = annotationVisibility;
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the given StaticFinalFieldMatchProcessor if classes are found on the classpath that contain static
* final fields that match one of a set of fully-qualified field names, e.g.
* "com.package.ClassName.STATIC_FIELD_NAME".
*
*
* Field values are obtained from the constant pool in classfiles, not from a loaded class using reflection.
* This allows you to detect changes to the classpath and then run another scan that picks up the new values of
* selected static constants without reloading the class. (Class reloading is fraught with issues, see:
* http://tutorials.jenkov.com/java-reflection/dynamic-class-loading-reloading.html )
*
*
* Note: Only static final fields with constant-valued literals are matched, not fields with initializer values
* that are the result of an expression or reference, except for cases where the compiler is able to simplify an
* expression into a single constant at compiletime, such as in the case of string concatenation.
*
*
* Note that the visibility of the fields is not checked if ignoreFieldVisibility() was called before scan().
*
* @param fullyQualifiedStaticFinalFieldNames
* The set of fully-qualified static field names to match.
* @param staticFinalFieldMatchProcessor
* the StaticFinalFieldMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchStaticFinalFieldNames(final Set fullyQualifiedStaticFinalFieldNames,
final StaticFinalFieldMatchProcessor staticFinalFieldMatchProcessor) {
getScanSpec().matchStaticFinalFieldNames(fullyQualifiedStaticFinalFieldNames,
staticFinalFieldMatchProcessor);
return this;
}
/**
* Calls the given StaticFinalFieldMatchProcessor if classes are found on the classpath that contain static
* final fields that match a fully-qualified field name, e.g. "com.package.ClassName.STATIC_FIELD_NAME".
*
*
* Field values are obtained from the constant pool in classfiles, *not* from a loaded class using reflection.
* This allows you to detect changes to the classpath and then run another scan that picks up the new values of
* selected static constants without reloading the class. (Class reloading is fraught with issues, see:
* http://tutorials.jenkov.com/java-reflection/dynamic-class-loading-reloading.html )
*
*
* Note: Only static final fields with constant-valued literals are matched, not fields with initializer values
* that are the result of an expression or reference, except for cases where the compiler is able to simplify an
* expression into a single constant at compiletime, such as in the case of string concatenation.
*
*
* Note that the visibility of the fields is not checked if ignoreFieldVisibility() was called before scan().
*
* @param fullyQualifiedStaticFinalFieldName
* The fully-qualified static field name to match
* @param staticFinalFieldMatchProcessor
* the StaticFinalFieldMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchStaticFinalFieldNames(final String fullyQualifiedStaticFinalFieldName,
final StaticFinalFieldMatchProcessor staticFinalFieldMatchProcessor) {
getScanSpec().matchStaticFinalFieldNames(fullyQualifiedStaticFinalFieldName,
staticFinalFieldMatchProcessor);
return this;
}
/**
* Calls the given StaticFinalFieldMatchProcessor if classes are found on the classpath that contain static
* final fields that match one of a list of fully-qualified field names, e.g.
* "com.package.ClassName.STATIC_FIELD_NAME".
*
*
* Field values are obtained from the constant pool in classfiles, *not* from a loaded class using reflection.
* This allows you to detect changes to the classpath and then run another scan that picks up the new values of
* selected static constants without reloading the class. (Class reloading is fraught with issues, see:
* http://tutorials.jenkov.com/java-reflection/dynamic-class-loading-reloading.html )
*
*
* Note: Only static final fields with constant-valued literals are matched, not fields with initializer values
* that are the result of an expression or reference, except for cases where the compiler is able to simplify an
* expression into a single constant at compiletime, such as in the case of string concatenation.
*
*
* Note that the visibility of the fields is not checked if ignoreFieldVisibility() was called before scan().
*
* @param fullyQualifiedStaticFinalFieldNames
* The list of fully-qualified static field names to match.
* @param staticFinalFieldMatchProcessor
* the StaticFinalFieldMatchProcessor to call when a match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchStaticFinalFieldNames(final String[] fullyQualifiedStaticFinalFieldNames,
final StaticFinalFieldMatchProcessor staticFinalFieldMatchProcessor) {
getScanSpec().matchStaticFinalFieldNames(fullyQualifiedStaticFinalFieldNames,
staticFinalFieldMatchProcessor);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the given FilenameMatchProcessor if files are found on the classpath with the given regexp pattern in
* their path.
*
* @param pathRegexp
* The regexp to match, e.g. "app/templates/.*\\.html"
* @param filenameMatchProcessor
* The FilenameMatchProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePattern(final String pathRegexp,
final FilenameMatchProcessor filenameMatchProcessor) {
getScanSpec().matchFilenamePattern(pathRegexp, filenameMatchProcessor);
return this;
}
/**
* Calls the given FileMatchProcessor if files are found on the classpath with the given regexp pattern in their
* path.
*
* @param pathRegexp
* The regexp to match, e.g. "app/templates/.*\\.html"
* @param fileMatchProcessor
* The FileMatchProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePattern(final String pathRegexp,
final FileMatchProcessor fileMatchProcessor) {
getScanSpec().matchFilenamePattern(pathRegexp, fileMatchProcessor);
return this;
}
/**
* Calls the given FileMatchContentsProcessor if files are found on the classpath with the given regexp pattern
* in their path.
*
* @param pathRegexp
* The regexp to match, e.g. "app/templates/.*\\.html"
* @param fileMatchContentsProcessor
* The FileMatchContentsProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePattern(final String pathRegexp,
final FileMatchContentsProcessor fileMatchContentsProcessor) {
getScanSpec().matchFilenamePattern(pathRegexp, fileMatchContentsProcessor);
return this;
}
/**
* Calls the given FileMatchProcessorWithContext if files are found on the classpath with the given regexp
* pattern in their path.
*
* @param pathRegexp
* The regexp to match, e.g. "app/templates/.*\\.html"
* @param fileMatchProcessorWithContext
* The FileMatchProcessorWithContext to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePattern(final String pathRegexp,
final FileMatchProcessorWithContext fileMatchProcessorWithContext) {
getScanSpec().matchFilenamePattern(pathRegexp, fileMatchProcessorWithContext);
return this;
}
/**
* Calls the given FileMatchContentsProcessorWithContext if files are found on the classpath with the given
* regexp pattern in their path.
*
* @param pathRegexp
* The regexp to match, e.g. "app/templates/.*\\.html"
* @param fileMatchContentsProcessorWithContext
* The FileMatchContentsProcessorWithContext to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePattern(final String pathRegexp,
final FileMatchContentsProcessorWithContext fileMatchContentsProcessorWithContext) {
getScanSpec().matchFilenamePattern(pathRegexp, fileMatchContentsProcessorWithContext);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the given FilenameMatchProcessor if files are found on the classpath that exactly match the given
* relative path.
*
* @param relativePathToMatch
* The complete path to match relative to the classpath entry, e.g.
* "app/templates/WidgetTemplate.html"
* @param filenameMatchProcessor
* The FilenameMatchProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePath(final String relativePathToMatch,
final FilenameMatchProcessor filenameMatchProcessor) {
getScanSpec().matchFilenamePath(relativePathToMatch, filenameMatchProcessor);
return this;
}
/**
* Calls the given FileMatchProcessor if files are found on the classpath that exactly match the given relative
* path.
*
* @param relativePathToMatch
* The complete path to match relative to the classpath entry, e.g.
* "app/templates/WidgetTemplate.html"
* @param fileMatchProcessor
* The FileMatchProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePath(final String relativePathToMatch,
final FileMatchProcessor fileMatchProcessor) {
getScanSpec().matchFilenamePath(relativePathToMatch, fileMatchProcessor);
return this;
}
/**
* Calls the given FileMatchContentsProcessor if files are found on the classpath that exactly match the given
* relative path.
*
* @param relativePathToMatch
* The complete path to match relative to the classpath entry, e.g.
* "app/templates/WidgetTemplate.html"
* @param fileMatchContentsProcessor
* The FileMatchContentsProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePath(final String relativePathToMatch,
final FileMatchContentsProcessor fileMatchContentsProcessor) {
getScanSpec().matchFilenamePath(relativePathToMatch, fileMatchContentsProcessor);
return this;
}
/**
* Calls the given FileMatchProcessorWithContext if files are found on the classpath that exactly match the
* given relative path.
*
* @param relativePathToMatch
* The complete path to match relative to the classpath entry, e.g.
* "app/templates/WidgetTemplate.html"
* @param fileMatchProcessorWithContext
* The FileMatchProcessorWithContext to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePath(final String relativePathToMatch,
final FileMatchProcessorWithContext fileMatchProcessorWithContext) {
getScanSpec().matchFilenamePath(relativePathToMatch, fileMatchProcessorWithContext);
return this;
}
/**
* Calls the given FileMatchContentsProcessorWithContext if files are found on the classpath that exactly match
* the given relative path.
*
* @param relativePathToMatch
* The complete path to match relative to the classpath entry, e.g.
* "app/templates/WidgetTemplate.html"
* @param fileMatchContentsProcessorWithContext
* The FileMatchContentsProcessorWithContext to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePath(final String relativePathToMatch,
final FileMatchContentsProcessorWithContext fileMatchContentsProcessorWithContext) {
getScanSpec().matchFilenamePath(relativePathToMatch, fileMatchContentsProcessorWithContext);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the given FilenameMatchProcessor if files are found on the classpath that exactly match the given path
* leafname.
*
* @param pathLeafToMatch
* The complete path leaf to match, e.g. "WidgetTemplate.html"
* @param filenameMatchProcessor
* The FilenameMatchProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePathLeaf(final String pathLeafToMatch,
final FilenameMatchProcessor filenameMatchProcessor) {
getScanSpec().matchFilenamePathLeaf(pathLeafToMatch, filenameMatchProcessor);
return this;
}
/**
* Calls the given FileMatchProcessor if files are found on the classpath that exactly match the given path
* leafname.
*
* @param pathLeafToMatch
* The complete path leaf to match, e.g. "WidgetTemplate.html"
* @param fileMatchProcessor
* The FileMatchProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePathLeaf(final String pathLeafToMatch,
final FileMatchProcessor fileMatchProcessor) {
getScanSpec().matchFilenamePathLeaf(pathLeafToMatch, fileMatchProcessor);
return this;
}
/**
* Calls the given FileMatchContentsProcessor if files are found on the classpath that exactly match the given
* path leafname.
*
* @param pathLeafToMatch
* The complete path leaf to match, e.g. "WidgetTemplate.html"
* @param fileMatchContentsProcessor
* The FileMatchContentsProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePathLeaf(final String pathLeafToMatch,
final FileMatchContentsProcessor fileMatchContentsProcessor) {
getScanSpec().matchFilenamePathLeaf(pathLeafToMatch, fileMatchContentsProcessor);
return this;
}
/**
* Calls the given FileMatchProcessorWithContext if files are found on the classpath that exactly match the
* given path leafname.
*
* @param pathLeafToMatch
* The complete path leaf to match, e.g. "WidgetTemplate.html"
* @param fileMatchProcessorWithContext
* The FileMatchProcessorWithContext to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePathLeaf(final String pathLeafToMatch,
final FileMatchProcessorWithContext fileMatchProcessorWithContext) {
getScanSpec().matchFilenamePathLeaf(pathLeafToMatch, fileMatchProcessorWithContext);
return this;
}
/**
* Calls the given FileMatchContentsProcessorWithContext if files are found on the classpath that exactly match
* the given path leafname.
*
* @param pathLeafToMatch
* The complete path leaf to match, e.g. "WidgetTemplate.html"
* @param fileMatchContentsProcessorWithContext
* The FileMatchContentsProcessorWithContext to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenamePathLeaf(final String pathLeafToMatch,
final FileMatchContentsProcessorWithContext fileMatchContentsProcessorWithContext) {
getScanSpec().matchFilenamePathLeaf(pathLeafToMatch, fileMatchContentsProcessorWithContext);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Calls the given FilenameMatchProcessor if files are found on the classpath that have the given file
* extension.
*
* @param extensionToMatch
* The extension to match, e.g. "html" matches "WidgetTemplate.html" and "WIDGET.HTML".
* @param filenameMatchProcessor
* The FilenameMatchProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenameExtension(final String extensionToMatch,
final FilenameMatchProcessor filenameMatchProcessor) {
getScanSpec().matchFilenameExtension(extensionToMatch, filenameMatchProcessor);
return this;
}
/**
* Calls the given FileMatchProcessor if files are found on the classpath that have the given file extension.
*
* @param extensionToMatch
* The extension to match, e.g. "html" matches "WidgetTemplate.html" and "WIDGET.HTML".
* @param fileMatchProcessor
* The FileMatchProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenameExtension(final String extensionToMatch,
final FileMatchProcessor fileMatchProcessor) {
getScanSpec().matchFilenameExtension(extensionToMatch, fileMatchProcessor);
return this;
}
/**
* Calls the given FileMatchProcessor if files are found on the classpath that have the given file extension.
*
* @param extensionToMatch
* The extension to match, e.g. "html" matches "WidgetTemplate.html".
* @param fileMatchContentsProcessor
* The FileMatchContentsProcessor to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenameExtension(final String extensionToMatch,
final FileMatchContentsProcessor fileMatchContentsProcessor) {
getScanSpec().matchFilenameExtension(extensionToMatch, fileMatchContentsProcessor);
return this;
}
/**
* Calls the given FileMatchProcessorWithContext if files are found on the classpath that have the given file
* extension.
*
* @param extensionToMatch
* The extension to match, e.g. "html" matches "WidgetTemplate.html" and "WIDGET.HTML".
* @param fileMatchProcessorWithContext
* The FileMatchProcessorWithContext to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenameExtension(final String extensionToMatch,
final FileMatchProcessorWithContext fileMatchProcessorWithContext) {
getScanSpec().matchFilenameExtension(extensionToMatch, fileMatchProcessorWithContext);
return this;
}
/**
* Calls the given FileMatchProcessorWithContext if files are found on the classpath that have the given file
* extension.
*
* @param extensionToMatch
* The extension to match, e.g. "html" matches "WidgetTemplate.html".
* @param fileMatchContentsProcessorWithContext
* The FileMatchContentsProcessorWithContext to call when each match is found.
* @return this (for method chaining).
*/
public FastClasspathScanner matchFilenameExtension(final String extensionToMatch,
final FileMatchContentsProcessorWithContext fileMatchContentsProcessorWithContext) {
getScanSpec().matchFilenameExtension(extensionToMatch, fileMatchContentsProcessorWithContext);
return this;
}
// -------------------------------------------------------------------------------------------------------------
/**
* Asynchronously scans the classpath for matching files, and if scanResultProcessor is non-null, also calls any
* MatchProcessors if a match is identified.
*
* @param executorService
* A custom ExecutorService to use for scheduling worker tasks.
* @param numParallelTasks
* The number of parallel tasks to break the work into during the most CPU-intensive stage of
* classpath scanning. Ideally the ExecutorService will have at least this many threads available.
* @param isAsyncScan
* If true, this is an async scan -- don't allow running from class initializers, in order to prevent
* a class initializer deadlock.
* @param scanResultProcessor
* If non-null, specifies a callback to run on the ScanResult after asynchronous scanning has
* completed and MatchProcessors have been run.
* @param failureHandler
* If non-null, specifies a callback to run if an exception is thrown during an asynchronous scan. If
* a FailureHandler is provided and an exception is thrown, the resulting Future's get() method will
* return null rather than throwing an ExecutionException.
* @return a Future object, that when resolved using get() yields a new ScanResult object. You can
* call cancel(true) on this Future if you want to interrupt the scan.
*/
private Future launchAsyncScan(final ExecutorService executorService, final int numParallelTasks,
final boolean isAsyncScan, final ScanResultProcessor scanResultProcessor,
final FailureHandler failureHandler) {
final ScanSpec scanSpec = getScanSpec();
if (isAsyncScan && scanSpec.hasMatchProcessors()) {
// Disallow MatchProcessors when launched asynchronously from a class initializer, to prevent class
// initializer deadlock if any of the MatchProcessors try to refer to the incompletely-initialized class
// -- see bug #103.
try {
try {
// Generate stacktrace, so that we can get caller info
throw new Exception();
} catch (final Exception e) {
final StackTraceElement[] elts = e.getStackTrace();
for (final StackTraceElement elt : elts) {
if ("".equals(elt.getMethodName())) {
throw new RuntimeException("Cannot use MatchProcessors while launching a scan "
+ "from a class initialization block (for class " + elt.getClassName()
+ "), as this can lead to a class initializer deadlock. See: "
+ "https://github.com/lukehutch/fast-classpath-scanner/issues/103");
}
}
}
} catch (final RuntimeException e) {
// Re-catch the RuntimeException so we have the stacktrace for the above failure
if (failureHandler == null) {
throw e;
} else {
if (log != null) {
log.log(e);
log.flush();
}
failureHandler.onFailure(e);
return executorService.submit(new Callable() {
@Override
public ScanResult call() throws Exception {
// Return null from the Future if a FailureHandler was added and there was an exception
return null;
}
});
}
}
}
return executorService.submit(
// Call MatchProcessors before returning if in async scanning mode
new Scanner(scanSpec, executorService, numParallelTasks, /* enableRecursiveScanning = */ true,
scanResultProcessor, failureHandler, log));
}
/**
* Asynchronously scans the classpath for matching files, and if runAsynchronously is true, also calls any
* MatchProcessors if a match is identified.
*
* @param executorService
* A custom ExecutorService to use for scheduling worker tasks.
* @param numParallelTasks
* The number of parallel tasks to break the work into during the most CPU-intensive stage of
* classpath scanning. Ideally the ExecutorService will have at least this many threads available.
* @param scanResultProcessor
* A callback to run on successful scan. Passed the ScanResult after asynchronous scanning has
* completed and MatchProcessors have been run. (If null, throws IllegalArgumentException.)
* @param failureHandler
* A callback to run on failed scan. Passed any Throwable thrown during the scan. (If null, throws
* IllegalArgumentException.)
*/
public void scanAsync(final ExecutorService executorService, final int numParallelTasks,
final ScanResultProcessor scanResultProcessor, final FailureHandler failureHandler) {
if (scanResultProcessor == null) {
// If scanResultProcessor is null, the scan won't do anything after completion, and the ScanResult will
// simply be lost.
throw new IllegalArgumentException("scanResultProcessor cannot be null");
}
if (failureHandler == null) {
// The result of the Future object returned by launchAsyncScan is discarded below, so we
// force the addition of a FailureHandler so that exceptions are not silently swallowed.
throw new IllegalArgumentException("failureHandler cannot be null");
}
// Drop the returned Future, a ScanResultProcessor is used instead
launchAsyncScan(executorService, numParallelTasks, /* isAsyncScan = */ true, new ScanResultProcessor() {
@Override
public void processScanResult(final ScanResult scanResult) {
// Call any MatchProcessors after scan has completed
getScanSpec().callMatchProcessors(scanResult);
// Call the provided ScanResultProcessor
scanResultProcessor.processScanResult(scanResult);
// Free temporary files if necessary
if (scanSpec.removeTemporaryFilesAfterScan) {
scanResult.freeTempFiles(log);
}
}
}, failureHandler);
}
/**
* Asynchronously scans the classpath for matching files, and if runAsynchronously is true, also calls any
* MatchProcessors if a match is identified.
*
* @param executorService
* A custom ExecutorService to use for scheduling worker tasks.
* @param numParallelTasks
* The number of parallel tasks to break the work into during the most CPU-intensive stage of
* classpath scanning. Ideally the ExecutorService will have at least this many threads available.
* @param runMatchProcessorsOnWorkerThread
* If true, run MatchProcessors in one of the worker threads after obtaining the ScanResult.
* @return a Future object, that when resolved using get() yields a new ScanResult object. You can
* call cancel(true) on this Future if you want to interrupt the scan.
*/
private Future scanAsync(final ExecutorService executorService, final int numParallelTasks,
final boolean isAsyncScan, final boolean runMatchProcessorsOnWorkerThread) {
return launchAsyncScan(executorService, numParallelTasks, isAsyncScan,
runMatchProcessorsOnWorkerThread ? new ScanResultProcessor() {
@Override
public void processScanResult(final ScanResult scanResult) {
// Call MatchProcessors after scan has completed
getScanSpec().callMatchProcessors(scanResult);
// Free temporary files if necessary
if (scanSpec.removeTemporaryFilesAfterScan) {
scanResult.freeTempFiles(log);
}
}
} : null, /* failureHandler = */ null);
}
/**
* Asynchronously scans the classpath for matching files, and calls any MatchProcessors if a match is
* identified. Returns a Future object immediately after starting the scan. To block on scan completion, get the
* result of the returned Future. Uses the provided ExecutorService, and divides the work according to the
* requested degree of parallelism. This method should be called after all required MatchProcessors have been
* added.
*
*
* Note on thread safety: MatchProcessors are all run on a separate thread from the thread that calls this
* method (although the MatchProcessors are all run on one thread). You will need to add your own
* synchronization logic if MatchProcessors interact with the main thread. See the following for more info:
*
*
* https://github.com/lukehutch/fast-classpath-scanner/wiki/1.-Usage#multithreading-issues
*
* @param executorService
* A custom ExecutorService to use for scheduling worker tasks.
* @param numParallelTasks
* The number of parallel tasks to break the work into during the most CPU-intensive stage of
* classpath scanning. Ideally the ExecutorService will have at least this many threads available.
* @return a Future object, that when resolved using get() yields a new ScanResult object. This
* ScanResult object contains info about the class graph within whitelisted packages encountered during
* the scan. Calling get() on this Future object throws InterruptedException if the scanning is
* interrupted before it completes, or throws ExecutionException if something goes wrong during
* scanning. If ExecutionException is thrown, and the cause is a MatchProcessorException, then either
* classloading failed for some class, or a MatchProcessor threw an exception.
*/
public Future scanAsync(final ExecutorService executorService, final int numParallelTasks) {
return scanAsync(executorService, numParallelTasks, /* isAsyncScan = */ true,
/* runMatchProcessorsOnWorkerThread = */ true);
}
/**
* Scans the classpath for matching files, and calls any MatchProcessors if a match is identified. Uses the
* provided ExecutorService, and divides the work according to the requested degree of parallelism. Blocks and
* waits for the scan to complete before returning a ScanResult. This method should be called after all required
* MatchProcessors have been added.
*
* @param executorService
* A custom ExecutorService to use for scheduling worker tasks. This ExecutorService should start
* tasks in FIFO order to avoid a deadlock during scan, i.e. be sure to construct the ExecutorService
* with a LinkedBlockingQueue as its task queue. (This is the default for
* Executors.newFixedThreadPool().)
* @param numParallelTasks
* The number of parallel tasks to break the work into during the most CPU-intensive stage of
* classpath scanning. Ideally the ExecutorService will have at least this many threads available.
* @throws MatchProcessorException
* if classloading fails for any of the classes matched by a MatchProcessor, or if a MatchProcessor
* throws an exception. If {@link FastClasspathScanner#suppressMatchProcessorExceptions()} is called
* before {@link FastClasspathScanner#scan()}, then {@link MatchProcessorException} will not be
* thrown at the end of scanning, and instead, any exceptions that were thrown by MatchProcessors
* can be fetched using {@link ScanResult#getMatchProcessorExceptions()}.
* @throws ScanInterruptedException
* if any of the worker threads are interrupted during the scan. If you care about thread
* interruption, you should catch this exception. If you don't plan to interrupt the scan, you
* probably don't need to catch this.
* @throws RuntimeException
* if any of the worker threads throws an uncaught exception. (Should not happen, this would
* indicate a bug in FastClasspathScanner.)
* @return a new ScanResult object, containing info about the class graph within whitelisted packages
* encountered during the scan.
*/
public ScanResult scan(final ExecutorService executorService, final int numParallelTasks) {
try {
// Start the scan, and then wait for scan completion
final ScanResult scanResult = scanAsync(executorService, numParallelTasks, /* isAsyncScan = */ false,
/* runMatchProcessorsOnWorkerThread = */ false).get();
// Call MatchProcessors in the same thread as the caller, to avoid deadlock (see bug #103)
getScanSpec().callMatchProcessors(scanResult);
// Free temporary files
if (scanSpec.removeTemporaryFilesAfterScan) {
scanResult.freeTempFiles(log);
}
// Return the scanResult after calling MatchProcessors
return scanResult;
} catch (final InterruptedException e) {
if (log != null) {
log.log("Scan interrupted");
}
throw new ScanInterruptedException();
} catch (final ExecutionException e) {
Throwable cause = e.getCause();
if (cause == null) {
cause = e;
}
if (cause instanceof InterruptedException) {
if (log != null) {
log.log("Scan interrupted");
}
throw new ScanInterruptedException();
} else if (cause instanceof MatchProcessorException) {
if (log != null) {
log.log("Exception during scan", e);
}
throw (MatchProcessorException) cause;
} else {
if (log != null) {
log.log("Unexpected exception during scan", e);
}
throw new RuntimeException(cause);
}
} finally {
if (log != null) {
log.flush();
}
}
}
/**
* Scans the classpath for matching files, and calls any MatchProcessors if a match is identified. Temporarily
* starts up a new fixed thread pool for scanning, with the requested number of threads. Blocks and waits for
* the scan to complete before returning a ScanResult. This method should be called after all required
* MatchProcessors have been added.
*
* @param numThreads
* The number of worker threads to start up.
* @throws MatchProcessorException
* if classloading fails for any of the classes matched by a MatchProcessor, or if a MatchProcessor
* throws an exception. If {@link FastClasspathScanner#suppressMatchProcessorExceptions()} is called
* before {@link FastClasspathScanner#scan()}, then {@link MatchProcessorException} will not be
* thrown at the end of scanning, and instead, any exceptions that were thrown by MatchProcessors
* can be fetched using {@link ScanResult#getMatchProcessorExceptions()}.
* @throws ScanInterruptedException
* if any of the worker threads are interrupted during the scan (shouldn't happen under normal
* circumstances).
* @throws RuntimeException
* if any of the worker threads throws an uncaught exception. (Should not happen, this would
* indicate a bug in FastClasspathScanner.)
* @return a new ScanResult object, containing info about the class graph within whitelisted packages
* encountered during the scan.
*/
public ScanResult scan(final int numThreads) {
try (AutoCloseableExecutorService executorService = new AutoCloseableExecutorService(numThreads)) {
return scan(executorService, numThreads);
}
}
/**
* Scans the classpath for matching files, and calls any MatchProcessors if a match is identified. Temporarily
* starts up a new fixed thread pool for scanning, with the default number of threads. Blocks and waits for the
* scan to complete before returning a ScanResult. This method should be called after all required
* MatchProcessors have been added.
*
* @throws MatchProcessorException
* if classloading fails for any of the classes matched by a MatchProcessor, or if a MatchProcessor
* throws an exception. If {@link FastClasspathScanner#suppressMatchProcessorExceptions()} is called
* before {@link FastClasspathScanner#scan()}, then {@link MatchProcessorException} will not be
* thrown at the end of scanning, and instead, any exceptions that were thrown by MatchProcessors
* can be fetched using {@link ScanResult#getMatchProcessorExceptions()}.
* @throws ScanInterruptedException
* if any of the worker threads are interrupted during the scan (shouldn't happen under normal
* circumstances).
* @throws RuntimeException
* if any of the worker threads throws an uncaught exception. (Should not happen, this would
* indicate a bug in FastClasspathScanner.)
* @return a new ScanResult object, containing info about the class graph within whitelisted packages
* encountered during the scan.
*/
public ScanResult scan() {
return scan(DEFAULT_NUM_WORKER_THREADS);
}
// -------------------------------------------------------------------------------------------------------------
/**
* Asynchronously returns the list of all unique File objects representing directories or zip/jarfiles on the
* classpath, in classloader resolution order. Classpath elements that do not exist are not included in the
* list.
*
*
* See the following for info on thread safety:
*
*
* https://github.com/lukehutch/fast-classpath-scanner/wiki/1.-Usage#multithreading-issues
*
*
* Note that if there are nested jarfiles on the classpath, e.g. {@code
* file:///path/to/jar1.jar!/path/to/jar2.jar}, then both FastClasspathScanner#scanAsync() and
* FastClasspathScanner#getUniqueClasspathElementsAsync() will cause jar2.jar to be extracted to a temporary
* file, however FastClasspathScanner#getUniqueClasspathElementsAsync() will not remove this temporary file
* after the scan (so that the file is still accessible to the caller -- each of the File objects in the
* returned list of classpath elements should exist). These extracted temporary files are marked for deletion on
* JVM exit, however.
*
* @param executorService
* A custom ExecutorService to use for scheduling worker tasks.
* @param numParallelTasks
* The number of parallel tasks to break the work into during the most CPU-intensive stage of
* classpath scanning. Ideally the ExecutorService will have at least this many threads available.
* @return a {@code Future>}, that when resolved with get() returns a list of the unique directories
* and jarfiles on the classpath, in classpath resolution order. You can call cancel(true) on this
* Future if you want to interrupt the process (although the result is typically returned quickly).
*/
public Future> getUniqueClasspathElementsAsync(final ExecutorService executorService,
final int numParallelTasks) {
// No need to call disallowCallingFromClassInitializer() here, because no MatchProcessors are run, so class
// initializer deadlock cannot occur.
final Future> classpathElementsFuture;
try {
final Future scanResultFuture = executorService.submit( //
new Scanner(getScanSpec(), executorService, numParallelTasks,
/* enableRecursiveScanning = */ false, /* scanResultProcessor = */ null,
/* failureHandler = */ null,
log == null ? null : log.log("Getting unique classpath elements")));
classpathElementsFuture = executorService.submit(new Callable>() {
@Override
public List call() throws Exception {
final ScanResult scanResult = scanResultFuture.get();
final List uniqueClasspathElements = scanResult.getUniqueClasspathElements();
// N.B. scanResult.freeTempFiles() is *not* called for this method, so that the classpath
// elements resulting from jars within jars are left in place. However, they are cleaned up on
// normal JVM exit.
return uniqueClasspathElements;
}
});
} finally {
if (log != null) {
log.flush();
}
}
return classpathElementsFuture;
}
/**
* Returns the list of all unique File objects representing directories or zip/jarfiles on the classpath, in
* classloader resolution order. Classpath elements that do not exist are not included in the list. Blocks until
* the result can be returned, when all classpath elements have been found and tested to see if they exist in
* the filesystem.
*
*
* Note that if there are nested jarfiles on the classpath, e.g. {@code
* file:///path/to/jar1.jar!/path/to/jar2.jar}, then both FastClasspathScanner#scan() and
* FastClasspathScanner#getUniqueClasspathElements() will cause jar2.jar to be extracted to a temporary file,
* however FastClasspathScanner#getUniqueClasspathElements() will not remove this temporary file after the scan
* (so that the file is still accessible to the caller -- each of the File objects in the returned list of
* classpath elements should exist). These extracted temporary files are marked for deletion on JVM exit,
* however.
*
* @param executorService
* A custom ExecutorService to use for scheduling worker tasks.
* @param numParallelTasks
* The number of parallel tasks to break the work into during the most CPU-intensive stage of
* classpath scanning. Ideally the ExecutorService will have at least this many threads available.
* @throws ScanInterruptedException
* if any of the worker threads are interrupted during the scan. If you care about thread
* interruption, you should catch this exception. If you don't plan to interrupt the scan, you
* probably don't need to catch this.
* @return a {@code List} consisting of the unique directories and jarfiles on the classpath, in classpath
* resolution order.
*/
public List getUniqueClasspathElements(final ExecutorService executorService,
final int numParallelTasks) {
if (classpathElts == null) {
try {
classpathElts = getUniqueClasspathElementsAsync(executorService, numParallelTasks).get();
} catch (final InterruptedException e) {
if (log != null) {
log.log("Thread interrupted while getting classpath elements");
}
throw new ScanInterruptedException();
} catch (final ExecutionException e) {
if (log != null) {
log.log("Exception while getting classpath elements", e);
}
final Throwable cause = e.getCause();
throw new RuntimeException(cause == null ? e : cause);
} finally {
if (log != null) {
log.flush();
}
}
}
return classpathElts;
}
/**
* Returns the list of all unique File objects representing directories or zip/jarfiles on the classpath, in
* classloader resolution order. Classpath elements that do not exist are not included in the list. Blocks until
* the result can be returned, when all classpath elements have been found and tested to see if they exist in
* the filesystem.
*
*
* Note that if there are nested jarfiles on the classpath, e.g. {@code
* file:///path/to/jar1.jar!/path/to/jar2.jar}, then both FastClasspathScanner#scan() and
* FastClasspathScanner#getUniqueClasspathElements() will cause jar2.jar to be extracted to a temporary file,
* however FastClasspathScanner#getUniqueClasspathElements() will not remove this temporary file after the scan
* (so that the file is still accessible to the caller -- each of the File objects in the returned list of
* classpath elements should exist). These extracted temporary files are marked for deletion on JVM exit,
* however.
*
* @throws ScanInterruptedException
* if any of the worker threads are interrupted during the scan (shouldn't happen under normal
* circumstances).
* @return a {@code List} consisting of the unique directories and jarfiles on the classpath, in classpath
* resolution order.
*/
public List getUniqueClasspathElements() {
if (classpathElts == null) {
try (AutoCloseableExecutorService executorService = new AutoCloseableExecutorService(
DEFAULT_NUM_WORKER_THREADS)) {
return getUniqueClasspathElements(executorService, DEFAULT_NUM_WORKER_THREADS);
}
}
return classpathElts;
}
/**
* Returns all unique directories or zip/jarfiles on the classpath, in classloader resolution order, as a
* classpath string, delineated with the standard path separator character. Classpath elements that do not exist
* are not included in the path. Blocks until the result can be returned, when all classpath elements have been
* found and tested to see if they exist in the filesystem.
*
*
* Note that if there are nested jarfiles on the classpath, e.g. {@code
* file:///path/to/jar1.jar!/path/to/jar2.jar}, then both FastClasspathScanner#scan() and
* FastClasspathScanner#getUniqueClasspathElements() will cause jar2.jar to be extracted to a temporary file,
* however FastClasspathScanner#getUniqueClasspathElements() will not remove this temporary file after the scan
* (so that the file is still accessible to the caller -- each of the File objects in the returned list of
* classpath elements should exist). These extracted temporary files are marked for deletion on JVM exit,
* however.
*
* @throws ScanInterruptedException
* if any of the worker threads are interrupted during the scan (shouldn't happen under normal
* circumstances).
* @return a the unique directories and jarfiles on the classpath, in classpath resolution order, as a path
* string.
*/
public String getUniqueClasspathElementsAsPathStr() {
return JarUtils.pathElementsToPathStr(getUniqueClasspathElements());
}
/**
* Asynchronously returns the list of all unique URLs representing directories or zip/jarfiles on the classpath,
* in classloader resolution order. Classpath elements that do not exist are not included in the list.
*
*
* See the following for info on thread safety:
*
*
* https://github.com/lukehutch/fast-classpath-scanner/wiki/1.-Usage#multithreading-issues
*
*
* Note that if there are nested jarfiles on the classpath, e.g. {@code
* file:///path/to/jar1.jar!/path/to/jar2.jar}, then both FastClasspathScanner#scanAsync() and
* FastClasspathScanner#getUniqueClasspathElementsAsync() will cause jar2.jar to be extracted to a temporary
* file, however FastClasspathScanner#getUniqueClasspathElementURLsAsync() will not remove this temporary file
* after the scan (so that the file is still accessible to the caller -- each of the File objects in the
* returned list of classpath elements should exist). These extracted temporary files are marked for deletion on
* JVM exit, however.
*
* @param executorService
* A custom ExecutorService to use for scheduling worker tasks.
* @param numParallelTasks
* The number of parallel tasks to break the work into during the most CPU-intensive stage of
* classpath scanning. Ideally the ExecutorService will have at least this many threads available.
* @return a {@code Future>}, that when resolved with get() returns a list of URLs for the unique
* directories and jarfiles on the classpath, in classpath resolution order. You can call cancel(true)
* on this Future if you want to interrupt the process (although the result is typically returned
* quickly).
*/
public Future> getUniqueClasspathElementURLsAsync(final ExecutorService executorService,
final int numParallelTasks) {
// No need to call disallowCallingFromClassInitializer() here, because no MatchProcessors are run, so class
// initializer deadlock cannot occur.
final Future> classpathElementsFuture;
try {
final Future scanResultFuture = executorService.submit( //
new Scanner(getScanSpec(), executorService, numParallelTasks,
/* enableRecursiveScanning = */ false, /* scanResultProcessor = */ null,
/* failureHandler = */ null,
log == null ? null : log.log("Getting unique classpath elements")));
classpathElementsFuture = executorService.submit(new Callable>() {
@Override
public List call() throws Exception {
final ScanResult scanResult = scanResultFuture.get();
final List uniqueClasspathElementURLs = scanResult.getUniqueClasspathElementURLs();
// N.B. scanResult.freeTempFiles() is *not* called for this method, so that the classpath
// elements resulting from jars within jars are left in place. However, they are cleaned up on
// normal JVM exit.
return uniqueClasspathElementURLs;
}
});
} finally {
if (log != null) {
log.flush();
}
}
return classpathElementsFuture;
}
/**
* Returns the list of all unique URL objects representing directories or zip/jarfiles on the classpath, in
* classloader resolution order. Classpath elements that do not exist are not included in the list. Blocks until
* the result can be returned, when all classpath elements have been found and tested to see if they exist in
* the filesystem.
*
*
* Note that if there are nested jarfiles on the classpath, e.g. {@code
* file:///path/to/jar1.jar!/path/to/jar2.jar}, then both FastClasspathScanner#scan() and
* FastClasspathScanner#getUniqueClasspathElements() will cause jar2.jar to be extracted to a temporary file,
* however FastClasspathScanner#getUniqueClasspathElementURLs() will not remove this temporary file after the
* scan (so that the file is still accessible to the caller -- each of the File objects in the returned list of
* classpath elements should exist). These extracted temporary files are marked for deletion on JVM exit,
* however.
*
* @param executorService
* A custom ExecutorService to use for scheduling worker tasks.
* @param numParallelTasks
* The number of parallel tasks to break the work into during the most CPU-intensive stage of
* classpath scanning. Ideally the ExecutorService will have at least this many threads available.
* @throws ScanInterruptedException
* if any of the worker threads are interrupted during the scan. If you care about thread
* interruption, you should catch this exception. If you don't plan to interrupt the scan, you
* probably don't need to catch this.
* @return a {@code List} consisting of the unique directories and jarfiles on the classpath, in classpath
* resolution order.
*/
public List getUniqueClasspathElementURLs(final ExecutorService executorService,
final int numParallelTasks) {
if (classpathEltURLs == null) {
try {
classpathEltURLs = getUniqueClasspathElementURLsAsync(executorService, numParallelTasks).get();
} catch (final InterruptedException e) {
if (log != null) {
log.log("Thread interrupted while getting classpath elements");
}
throw new ScanInterruptedException();
} catch (final ExecutionException e) {
if (log != null) {
log.log("Exception while getting classpath elements", e);
}
final Throwable cause = e.getCause();
throw new RuntimeException(cause == null ? e : cause);
} finally {
if (log != null) {
log.flush();
}
}
}
return classpathEltURLs;
}
/**
* Returns the list of all unique URL objects representing directories or zip/jarfiles on the classpath, in
* classloader resolution order. Classpath elements that do not exist are not included in the list. Blocks until
* the result can be returned, when all classpath elements have been found and tested to see if they exist in
* the filesystem.
*
*
* Note that if there are nested jarfiles on the classpath, e.g. {@code
* file:///path/to/jar1.jar!/path/to/jar2.jar}, then both FastClasspathScanner#scan() and
* FastClasspathScanner#getUniqueClasspathElements() will cause jar2.jar to be extracted to a temporary file,
* however FastClasspathScanner#getUniqueClasspathElementURLs() will not remove this temporary file after the
* scan (so that the file is still accessible to the caller -- each of the File objects in the returned list of
* classpath elements should exist). These extracted temporary files are marked for deletion on JVM exit,
* however.
*
* @throws ScanInterruptedException
* if any of the worker threads are interrupted during the scan (shouldn't happen under normal
* circumstances).
* @return a {@code List} consisting of the unique directories and jarfiles on the classpath, in classpath
* resolution order.
*/
public List getUniqueClasspathElementURLs() {
if (classpathEltURLs == null) {
try (AutoCloseableExecutorService executorService = new AutoCloseableExecutorService(
DEFAULT_NUM_WORKER_THREADS)) {
return getUniqueClasspathElementURLs(executorService, DEFAULT_NUM_WORKER_THREADS);
}
}
return classpathEltURLs;
}
}