org.springframework.aot.hint.support.FilePatternResourceHintsRegistrar Maven / Gradle / Ivy
/*
* Copyright 2002-2023 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.aot.hint.support;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.springframework.aot.hint.ResourceHints;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.ResourceUtils;
/**
* Register the necessary resource hints for loading files from the classpath,
* based on file name prefixes and file extensions with convenience to support
* multiple classpath locations.
*
* Only registers hints for matching classpath locations, which allows for
* several locations to be provided without contributing unnecessary hints.
*
* @author Stephane Nicoll
* @author Sam Brannen
* @since 6.0
*/
public class FilePatternResourceHintsRegistrar {
private final List classpathLocations;
private final List filePrefixes;
private final List fileExtensions;
/**
* Create a new instance for the specified file prefixes, classpath locations,
* and file extensions.
* @param filePrefixes the file prefixes
* @param classpathLocations the classpath locations
* @param fileExtensions the file extensions (starting with a dot)
* @deprecated as of 6.0.12 in favor of {@linkplain #forClassPathLocations(String...) the builder}
*/
@Deprecated(since = "6.0.12", forRemoval = true)
public FilePatternResourceHintsRegistrar(List filePrefixes, List classpathLocations,
List fileExtensions) {
this.classpathLocations = validateClasspathLocations(classpathLocations);
this.filePrefixes = validateFilePrefixes(filePrefixes);
this.fileExtensions = validateFileExtensions(fileExtensions);
}
@Deprecated(since = "6.0.12", forRemoval = true)
public void registerHints(ResourceHints hints, @Nullable ClassLoader classLoader) {
ClassLoader classLoaderToUse = (classLoader != null ? classLoader : getClass().getClassLoader());
List includes = new ArrayList<>();
for (String location : this.classpathLocations) {
if (classLoaderToUse.getResource(location) != null) {
for (String filePrefix : this.filePrefixes) {
for (String fileExtension : this.fileExtensions) {
includes.add(location + filePrefix + "*" + fileExtension);
}
}
}
}
if (!includes.isEmpty()) {
hints.registerPattern(hint -> hint.includes(includes.toArray(String[]::new)));
}
}
/**
* Configure the registrar with the specified
* {@linkplain Builder#withClasspathLocations(String...) classpath locations}.
* @param classpathLocations the classpath locations
* @return a {@link Builder} to further configure the registrar
* @since 6.0.12
* @see #forClassPathLocations(List)
*/
public static Builder forClassPathLocations(String... classpathLocations) {
return forClassPathLocations(Arrays.asList(classpathLocations));
}
/**
* Configure the registrar with the specified
* {@linkplain Builder#withClasspathLocations(List) classpath locations}.
* @param classpathLocations the classpath locations
* @return a {@link Builder} to further configure the registrar
* @since 6.0.12
* @see #forClassPathLocations(String...)
*/
public static Builder forClassPathLocations(List classpathLocations) {
return new Builder().withClasspathLocations(classpathLocations);
}
private static List validateClasspathLocations(List classpathLocations) {
Assert.notEmpty(classpathLocations, "At least one classpath location must be specified");
List parsedLocations = new ArrayList<>();
for (String location : classpathLocations) {
if (location.startsWith(ResourceUtils.CLASSPATH_URL_PREFIX)) {
location = location.substring(ResourceUtils.CLASSPATH_URL_PREFIX.length());
}
if (location.startsWith("/")) {
location = location.substring(1);
}
if (!location.isEmpty() && !location.endsWith("/")) {
location = location + "/";
}
parsedLocations.add(location);
}
return parsedLocations;
}
private static List validateFilePrefixes(List filePrefixes) {
for (String filePrefix : filePrefixes) {
if (filePrefix.contains("*")) {
throw new IllegalArgumentException("File prefix '" + filePrefix + "' cannot contain '*'");
}
}
return filePrefixes;
}
private static List validateFileExtensions(List fileExtensions) {
for (String fileExtension : fileExtensions) {
if (!fileExtension.startsWith(".")) {
throw new IllegalArgumentException("Extension '" + fileExtension + "' must start with '.'");
}
}
return fileExtensions;
}
/**
* Builder for {@link FilePatternResourceHintsRegistrar}.
* @since 6.0.12
*/
public static final class Builder {
private final List classpathLocations = new ArrayList<>();
private final List filePrefixes = new ArrayList<>();
private final List fileExtensions = new ArrayList<>();
private Builder() {
// no-op
}
/**
* Consider the specified classpath locations.
* A location can either be a special {@value ResourceUtils#CLASSPATH_URL_PREFIX}
* pseudo location or a standard location, such as {@code com/example/resources}.
* An empty String represents the root of the classpath.
* @param classpathLocations the classpath locations to consider
* @return this builder
* @see #withClasspathLocations(List)
*/
public Builder withClasspathLocations(String... classpathLocations) {
return withClasspathLocations(Arrays.asList(classpathLocations));
}
/**
* Consider the specified classpath locations.
*
A location can either be a special {@value ResourceUtils#CLASSPATH_URL_PREFIX}
* pseudo location or a standard location, such as {@code com/example/resources}.
* An empty String represents the root of the classpath.
* @param classpathLocations the classpath locations to consider
* @return this builder
* @see #withClasspathLocations(String...)
*/
public Builder withClasspathLocations(List classpathLocations) {
this.classpathLocations.addAll(validateClasspathLocations(classpathLocations));
return this;
}
/**
* Consider the specified file prefixes. Any file whose name starts with one
* of the specified prefixes is considered. A prefix cannot contain the {@code *}
* character.
* @param filePrefixes the file prefixes to consider
* @return this builder
* @see #withFilePrefixes(List)
*/
public Builder withFilePrefixes(String... filePrefixes) {
return withFilePrefixes(Arrays.asList(filePrefixes));
}
/**
* Consider the specified file prefixes. Any file whose name starts with one
* of the specified prefixes is considered. A prefix cannot contain the {@code *}
* character.
* @param filePrefixes the file prefixes to consider
* @return this builder
* @see #withFilePrefixes(String...)
*/
public Builder withFilePrefixes(List filePrefixes) {
this.filePrefixes.addAll(validateFilePrefixes(filePrefixes));
return this;
}
/**
* Consider the specified file extensions. A file extension must start with a
* {@code .} character.
* @param fileExtensions the file extensions to consider
* @return this builder
* @see #withFileExtensions(List)
*/
public Builder withFileExtensions(String... fileExtensions) {
return withFileExtensions(Arrays.asList(fileExtensions));
}
/**
* Consider the specified file extensions. A file extension must start with a
* {@code .} character.
* @param fileExtensions the file extensions to consider
* @return this builder
* @see #withFileExtensions(String...)
*/
public Builder withFileExtensions(List fileExtensions) {
this.fileExtensions.addAll(validateFileExtensions(fileExtensions));
return this;
}
private FilePatternResourceHintsRegistrar build() {
return new FilePatternResourceHintsRegistrar(this.filePrefixes,
this.classpathLocations, this.fileExtensions);
}
/**
* Register resource hints for the current state of this builder. For each
* classpath location that resolves against the {@code ClassLoader}, files
* with the configured file prefixes and extensions are registered.
* @param hints the hints contributed so far for the deployment unit
* @param classLoader the classloader, or {@code null} if even the system
* ClassLoader isn't accessible
*/
public void registerHints(ResourceHints hints, @Nullable ClassLoader classLoader) {
build().registerHints(hints, classLoader);
}
}
}