org.springframework.boot.loader.PropertiesLauncher Maven / Gradle / Ivy
/*
* Copyright 2012-2019 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.boot.loader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Locale;
import java.util.Properties;
import java.util.Set;
import java.util.jar.Manifest;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.springframework.boot.loader.archive.Archive;
import org.springframework.boot.loader.archive.Archive.Entry;
import org.springframework.boot.loader.archive.Archive.EntryFilter;
import org.springframework.boot.loader.archive.ExplodedArchive;
import org.springframework.boot.loader.archive.JarFileArchive;
import org.springframework.boot.loader.util.SystemPropertyUtils;
/**
* {@link Launcher} for archives with user-configured classpath and main class via a
* properties file. This model is often more flexible and more amenable to creating
* well-behaved OS-level services than a model based on executable jars.
*
* Looks in various places for a properties file to extract loader settings, defaulting to
* {@code loader.properties} either on the current classpath or in the current working
* directory. The name of the properties file can be changed by setting a System property
* {@code loader.config.name} (e.g. {@code -Dloader.config.name=foo} will look for
* {@code foo.properties}. If that file doesn't exist then tries
* {@code loader.config.location} (with allowed prefixes {@code classpath:} and
* {@code file:} or any valid URL). Once that file is located turns it into Properties and
* extracts optional values (which can also be provided overridden as System properties in
* case the file doesn't exist):
*
* - {@code loader.path}: a comma-separated list of directories (containing file
* resources and/or nested archives in *.jar or *.zip or archives) or archives to append
* to the classpath. {@code BOOT-INF/classes,BOOT-INF/lib} in the application archive are
* always used
* - {@code loader.main}: the main method to delegate execution to once the class loader
* is set up. No default, but will fall back to looking for a {@code Start-Class} in a
* {@code MANIFEST.MF}, if there is one in
${loader.home}/META-INF.
*
*
* @author Dave Syer
* @author Janne Valkealahti
* @author Andy Wilkinson
*/
public class PropertiesLauncher extends Launcher {
private static final String DEBUG = "loader.debug";
/**
* Properties key for main class. As a manifest entry can also be specified as
* {@code Start-Class}.
*/
public static final String MAIN = "loader.main";
/**
* Properties key for classpath entries (directories possibly containing jars or
* jars). Multiple entries can be specified using a comma-separated list. {@code
* BOOT-INF/classes,BOOT-INF/lib} in the application archive are always used.
*/
public static final String PATH = "loader.path";
/**
* Properties key for home directory. This is the location of external configuration
* if not on classpath, and also the base path for any relative paths in the
* {@link #PATH loader path}. Defaults to current working directory (
* ${user.dir}).
*/
public static final String HOME = "loader.home";
/**
* Properties key for default command line arguments. These arguments (if present) are
* prepended to the main method arguments before launching.
*/
public static final String ARGS = "loader.args";
/**
* Properties key for name of external configuration file (excluding suffix). Defaults
* to "application". Ignored if {@link #CONFIG_LOCATION loader config location} is
* provided instead.
*/
public static final String CONFIG_NAME = "loader.config.name";
/**
* Properties key for config file location (including optional classpath:, file: or
* URL prefix).
*/
public static final String CONFIG_LOCATION = "loader.config.location";
/**
* Properties key for boolean flag (default false) which if set will cause the
* external configuration properties to be copied to System properties (assuming that
* is allowed by Java security).
*/
public static final String SET_SYSTEM_PROPERTIES = "loader.system";
private static final Pattern WORD_SEPARATOR = Pattern.compile("\\W+");
private static final String NESTED_ARCHIVE_SEPARATOR = "!" + File.separator;
private final File home;
private List paths = new ArrayList<>();
private final Properties properties = new Properties();
private Archive parent;
public PropertiesLauncher() {
try {
this.home = getHomeDirectory();
initializeProperties();
initializePaths();
this.parent = createArchive();
}
catch (Exception ex) {
throw new IllegalStateException(ex);
}
}
protected File getHomeDirectory() {
try {
return new File(getPropertyWithDefault(HOME, "${user.dir}"));
}
catch (Exception ex) {
throw new IllegalStateException(ex);
}
}
private void initializeProperties() throws Exception, IOException {
List configs = new ArrayList<>();
if (getProperty(CONFIG_LOCATION) != null) {
configs.add(getProperty(CONFIG_LOCATION));
}
else {
String[] names = getPropertyWithDefault(CONFIG_NAME, "loader").split(",");
for (String name : names) {
configs.add("file:" + getHomeDirectory() + "/" + name + ".properties");
configs.add("classpath:" + name + ".properties");
configs.add("classpath:BOOT-INF/classes/" + name + ".properties");
}
}
for (String config : configs) {
try (InputStream resource = getResource(config)) {
if (resource != null) {
debug("Found: " + config);
loadResource(resource);
// Load the first one we find
return;
}
else {
debug("Not found: " + config);
}
}
}
}
private void loadResource(InputStream resource) throws IOException, Exception {
this.properties.load(resource);
for (Object key : Collections.list(this.properties.propertyNames())) {
String text = this.properties.getProperty((String) key);
String value = SystemPropertyUtils.resolvePlaceholders(this.properties, text);
if (value != null) {
this.properties.put(key, value);
}
}
if ("true".equals(getProperty(SET_SYSTEM_PROPERTIES))) {
debug("Adding resolved properties to System properties");
for (Object key : Collections.list(this.properties.propertyNames())) {
String value = this.properties.getProperty((String) key);
System.setProperty((String) key, value);
}
}
}
private InputStream getResource(String config) throws Exception {
if (config.startsWith("classpath:")) {
return getClasspathResource(config.substring("classpath:".length()));
}
config = handleUrl(config);
if (isUrl(config)) {
return getURLResource(config);
}
return getFileResource(config);
}
private String handleUrl(String path) throws UnsupportedEncodingException {
if (path.startsWith("jar:file:") || path.startsWith("file:")) {
path = URLDecoder.decode(path, "UTF-8");
if (path.startsWith("file:")) {
path = path.substring("file:".length());
if (path.startsWith("//")) {
path = path.substring(2);
}
}
}
return path;
}
private boolean isUrl(String config) {
return config.contains("://");
}
private InputStream getClasspathResource(String config) {
while (config.startsWith("/")) {
config = config.substring(1);
}
config = "/" + config;
debug("Trying classpath: " + config);
return getClass().getResourceAsStream(config);
}
private InputStream getFileResource(String config) throws Exception {
File file = new File(config);
debug("Trying file: " + config);
if (file.canRead()) {
return new FileInputStream(file);
}
return null;
}
private InputStream getURLResource(String config) throws Exception {
URL url = new URL(config);
if (exists(url)) {
URLConnection con = url.openConnection();
try {
return con.getInputStream();
}
catch (IOException ex) {
// Close the HTTP connection (if applicable).
if (con instanceof HttpURLConnection) {
((HttpURLConnection) con).disconnect();
}
throw ex;
}
}
return null;
}
private boolean exists(URL url) throws IOException {
// Try a URL connection content-length header...
URLConnection connection = url.openConnection();
try {
connection.setUseCaches(connection.getClass().getSimpleName().startsWith("JNLP"));
if (connection instanceof HttpURLConnection) {
HttpURLConnection httpConnection = (HttpURLConnection) connection;
httpConnection.setRequestMethod("HEAD");
int responseCode = httpConnection.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
return true;
}
else if (responseCode == HttpURLConnection.HTTP_NOT_FOUND) {
return false;
}
}
return (connection.getContentLength() >= 0);
}
finally {
if (connection instanceof HttpURLConnection) {
((HttpURLConnection) connection).disconnect();
}
}
}
private void initializePaths() throws Exception {
String path = getProperty(PATH);
if (path != null) {
this.paths = parsePathsProperty(path);
}
debug("Nested archive paths: " + this.paths);
}
private List parsePathsProperty(String commaSeparatedPaths) {
List paths = new ArrayList<>();
for (String path : commaSeparatedPaths.split(",")) {
path = cleanupPath(path);
// "" means the user wants root of archive but not current directory
path = "".equals(path) ? "/" : path;
paths.add(path);
}
if (paths.isEmpty()) {
paths.add("lib");
}
return paths;
}
protected String[] getArgs(String... args) throws Exception {
String loaderArgs = getProperty(ARGS);
if (loaderArgs != null) {
String[] defaultArgs = loaderArgs.split("\\s+");
String[] additionalArgs = args;
args = new String[defaultArgs.length + additionalArgs.length];
System.arraycopy(defaultArgs, 0, args, 0, defaultArgs.length);
System.arraycopy(additionalArgs, 0, args, defaultArgs.length, additionalArgs.length);
}
return args;
}
@Override
protected String getMainClass() throws Exception {
String mainClass = getProperty(MAIN, "Start-Class");
if (mainClass == null) {
throw new IllegalStateException("No '" + MAIN + "' or 'Start-Class' specified");
}
return mainClass;
}
@Override
protected ClassLoader createClassLoader(List archives) throws Exception {
Set urls = new LinkedHashSet<>(archives.size());
for (Archive archive : archives) {
urls.add(archive.getUrl());
}
ClassLoader loader = new LaunchedURLClassLoader(urls.toArray(new URL[0]), getClass().getClassLoader());
debug("Classpath: " + urls);
String customLoaderClassName = getProperty("loader.classLoader");
if (customLoaderClassName != null) {
loader = wrapWithCustomClassLoader(loader, customLoaderClassName);
debug("Using custom class loader: " + customLoaderClassName);
}
return loader;
}
@SuppressWarnings("unchecked")
private ClassLoader wrapWithCustomClassLoader(ClassLoader parent, String loaderClassName) throws Exception {
Class loaderClass = (Class) Class.forName(loaderClassName, true, parent);
try {
return loaderClass.getConstructor(ClassLoader.class).newInstance(parent);
}
catch (NoSuchMethodException ex) {
// Ignore and try with URLs
}
try {
return loaderClass.getConstructor(URL[].class, ClassLoader.class).newInstance(new URL[0], parent);
}
catch (NoSuchMethodException ex) {
// Ignore and try without any arguments
}
return loaderClass.newInstance();
}
private String getProperty(String propertyKey) throws Exception {
return getProperty(propertyKey, null, null);
}
private String getProperty(String propertyKey, String manifestKey) throws Exception {
return getProperty(propertyKey, manifestKey, null);
}
private String getPropertyWithDefault(String propertyKey, String defaultValue) throws Exception {
return getProperty(propertyKey, null, defaultValue);
}
private String getProperty(String propertyKey, String manifestKey, String defaultValue) throws Exception {
if (manifestKey == null) {
manifestKey = propertyKey.replace('.', '-');
manifestKey = toCamelCase(manifestKey);
}
String property = SystemPropertyUtils.getProperty(propertyKey);
if (property != null) {
String value = SystemPropertyUtils.resolvePlaceholders(this.properties, property);
debug("Property '" + propertyKey + "' from environment: " + value);
return value;
}
if (this.properties.containsKey(propertyKey)) {
String value = SystemPropertyUtils.resolvePlaceholders(this.properties,
this.properties.getProperty(propertyKey));
debug("Property '" + propertyKey + "' from properties: " + value);
return value;
}
try {
if (this.home != null) {
// Prefer home dir for MANIFEST if there is one
Manifest manifest = new ExplodedArchive(this.home, false).getManifest();
if (manifest != null) {
String value = manifest.getMainAttributes().getValue(manifestKey);
if (value != null) {
debug("Property '" + manifestKey + "' from home directory manifest: " + value);
return SystemPropertyUtils.resolvePlaceholders(this.properties, value);
}
}
}
}
catch (IllegalStateException ex) {
// Ignore
}
// Otherwise try the parent archive
Manifest manifest = createArchive().getManifest();
if (manifest != null) {
String value = manifest.getMainAttributes().getValue(manifestKey);
if (value != null) {
debug("Property '" + manifestKey + "' from archive manifest: " + value);
return SystemPropertyUtils.resolvePlaceholders(this.properties, value);
}
}
return (defaultValue != null) ? SystemPropertyUtils.resolvePlaceholders(this.properties, defaultValue)
: defaultValue;
}
@Override
protected List getClassPathArchives() throws Exception {
List lib = new ArrayList<>();
for (String path : this.paths) {
for (Archive archive : getClassPathArchives(path)) {
if (archive instanceof ExplodedArchive) {
List nested = new ArrayList<>(archive.getNestedArchives(new ArchiveEntryFilter()));
nested.add(0, archive);
lib.addAll(nested);
}
else {
lib.add(archive);
}
}
}
addNestedEntries(lib);
return lib;
}
private List getClassPathArchives(String path) throws Exception {
String root = cleanupPath(handleUrl(path));
List lib = new ArrayList<>();
File file = new File(root);
if (!"/".equals(root)) {
if (!isAbsolutePath(root)) {
file = new File(this.home, root);
}
if (file.isDirectory()) {
debug("Adding classpath entries from " + file);
Archive archive = new ExplodedArchive(file, false);
lib.add(archive);
}
}
Archive archive = getArchive(file);
if (archive != null) {
debug("Adding classpath entries from archive " + archive.getUrl() + root);
lib.add(archive);
}
List nestedArchives = getNestedArchives(root);
if (nestedArchives != null) {
debug("Adding classpath entries from nested " + root);
lib.addAll(nestedArchives);
}
return lib;
}
private boolean isAbsolutePath(String root) {
// Windows contains ":" others start with "/"
return root.contains(":") || root.startsWith("/");
}
private Archive getArchive(File file) throws IOException {
if (isNestedArchivePath(file)) {
return null;
}
String name = file.getName().toLowerCase(Locale.ENGLISH);
if (name.endsWith(".jar") || name.endsWith(".zip")) {
return new JarFileArchive(file);
}
return null;
}
private boolean isNestedArchivePath(File file) {
return file.getPath().contains(NESTED_ARCHIVE_SEPARATOR);
}
private List getNestedArchives(String path) throws Exception {
Archive parent = this.parent;
String root = path;
if (!root.equals("/") && root.startsWith("/") || parent.getUrl().equals(this.home.toURI().toURL())) {
// If home dir is same as parent archive, no need to add it twice.
return null;
}
int index = root.indexOf('!');
if (index != -1) {
File file = new File(this.home, root.substring(0, index));
if (root.startsWith("jar:file:")) {
file = new File(root.substring("jar:file:".length(), index));
}
parent = new JarFileArchive(file);
root = root.substring(index + 1);
while (root.startsWith("/")) {
root = root.substring(1);
}
}
if (root.endsWith(".jar")) {
File file = new File(this.home, root);
if (file.exists()) {
parent = new JarFileArchive(file);
root = "";
}
}
if (root.equals("/") || root.equals("./") || root.equals(".")) {
// The prefix for nested jars is actually empty if it's at the root
root = "";
}
EntryFilter filter = new PrefixMatchingArchiveFilter(root);
List archives = new ArrayList<>(parent.getNestedArchives(filter));
if (("".equals(root) || ".".equals(root)) && !path.endsWith(".jar") && parent != this.parent) {
// You can't find the root with an entry filter so it has to be added
// explicitly. But don't add the root of the parent archive.
archives.add(parent);
}
return archives;
}
private void addNestedEntries(List lib) {
// The parent archive might have "BOOT-INF/lib/" and "BOOT-INF/classes/"
// directories, meaning we are running from an executable JAR. We add nested
// entries from there with low priority (i.e. at end).
try {
lib.addAll(this.parent.getNestedArchives((entry) -> {
if (entry.isDirectory()) {
return entry.getName().equals(JarLauncher.BOOT_INF_CLASSES);
}
return entry.getName().startsWith(JarLauncher.BOOT_INF_LIB);
}));
}
catch (IOException ex) {
// Ignore
}
}
private String cleanupPath(String path) {
path = path.trim();
// No need for current dir path
if (path.startsWith("./")) {
path = path.substring(2);
}
String lowerCasePath = path.toLowerCase(Locale.ENGLISH);
if (lowerCasePath.endsWith(".jar") || lowerCasePath.endsWith(".zip")) {
return path;
}
if (path.endsWith("/*")) {
path = path.substring(0, path.length() - 1);
}
else {
// It's a directory
if (!path.endsWith("/") && !path.equals(".")) {
path = path + "/";
}
}
return path;
}
public static void main(String[] args) throws Exception {
PropertiesLauncher launcher = new PropertiesLauncher();
args = launcher.getArgs(args);
launcher.launch(args);
}
public static String toCamelCase(CharSequence string) {
if (string == null) {
return null;
}
StringBuilder builder = new StringBuilder();
Matcher matcher = WORD_SEPARATOR.matcher(string);
int pos = 0;
while (matcher.find()) {
builder.append(capitalize(string.subSequence(pos, matcher.end()).toString()));
pos = matcher.end();
}
builder.append(capitalize(string.subSequence(pos, string.length()).toString()));
return builder.toString();
}
private static String capitalize(String str) {
return Character.toUpperCase(str.charAt(0)) + str.substring(1);
}
private void debug(String message) {
if (Boolean.getBoolean(DEBUG)) {
System.out.println(message);
}
}
/**
* Convenience class for finding nested archives that have a prefix in their file path
* (e.g. "lib/").
*/
private static final class PrefixMatchingArchiveFilter implements EntryFilter {
private final String prefix;
private final ArchiveEntryFilter filter = new ArchiveEntryFilter();
private PrefixMatchingArchiveFilter(String prefix) {
this.prefix = prefix;
}
@Override
public boolean matches(Entry entry) {
if (entry.isDirectory()) {
return entry.getName().equals(this.prefix);
}
return entry.getName().startsWith(this.prefix) && this.filter.matches(entry);
}
}
/**
* Convenience class for finding nested archives (archive entries that can be
* classpath entries).
*/
private static final class ArchiveEntryFilter implements EntryFilter {
private static final String DOT_JAR = ".jar";
private static final String DOT_ZIP = ".zip";
@Override
public boolean matches(Entry entry) {
return entry.getName().endsWith(DOT_JAR) || entry.getName().endsWith(DOT_ZIP);
}
}
}