/* | |
* Licensed to the Apache Software Foundation (ASF) under one or more | |
* contributor license agreements. See the NOTICE file distributed with | |
* this work for additional information regarding copyright ownership. | |
* The ASF licenses this file to You 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 | |
* | |
* http://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.apache.bcel.util; | |
import java.io.Closeable; | |
import java.io.File; | |
import java.io.IOException; | |
import java.net.URI; | |
import java.net.URL; | |
import java.net.URLClassLoader; | |
import java.nio.file.DirectoryStream; | |
import java.nio.file.FileSystem; | |
import java.nio.file.FileSystems; | |
import java.nio.file.Files; | |
import java.nio.file.Path; | |
import java.nio.file.Paths; | |
import java.util.ArrayList; | |
import java.util.Collections; | |
import java.util.Iterator; | |
import java.util.List; | |
import java.util.Map; | |
/** | |
* Wraps a Java 9 JEP 220 modular runtime image. Requires the JRT NIO file system. | |
* | |
* @since 6.3 | |
*/ | |
public class ModularRuntimeImage implements Closeable { | |
static final String MODULES_PATH = File.separator + "modules"; | |
static final String PACKAGES_PATH = File.separator + "packages"; | |
private final URLClassLoader classLoader; | |
private final FileSystem fileSystem; | |
/** | |
* Constructs a default instance. | |
* | |
* @throws IOException | |
* an I/O error occurs accessing the file system | |
*/ | |
public ModularRuntimeImage() throws IOException { | |
this(null, FileSystems.getFileSystem(URI.create("jrt:/"))); | |
} | |
/** | |
* Constructs an instance using the JRT file system implementation from a specific Java Home. | |
* | |
* @param javaHome | |
* Path to a Java 9 or greater home. | |
* | |
* @throws IOException | |
* an I/O error occurs accessing the file system | |
*/ | |
public ModularRuntimeImage(final String javaHome) throws IOException { | |
final Map<String, ?> emptyMap = Collections.emptyMap(); | |
final Path jrePath = Paths.get(javaHome); | |
final Path jrtFsPath = jrePath.resolve("lib").resolve("jrt-fs.jar"); | |
this.classLoader = new URLClassLoader(new URL[] {jrtFsPath.toUri().toURL() }); | |
this.fileSystem = FileSystems.newFileSystem(URI.create("jrt:/"), emptyMap, classLoader); | |
} | |
private ModularRuntimeImage(final URLClassLoader cl, final FileSystem fs) { | |
this.classLoader = cl; | |
this.fileSystem = fs; | |
} | |
@Override | |
public void close() throws IOException { | |
if (classLoader != null) { | |
classLoader.close(); | |
} | |
if (fileSystem != null) { | |
fileSystem.close(); | |
} | |
} | |
/** | |
* Lists all entries in the given directory. | |
* | |
* @param dirPath | |
* directory path. | |
* @return a list of dir entries if an I/O error occurs | |
* @throws IOException | |
* an I/O error occurs accessing the file system | |
*/ | |
public List<Path> list(final Path dirPath) throws IOException { | |
final List<Path> list = new ArrayList<>(); | |
try (DirectoryStream<Path> ds = Files.newDirectoryStream(dirPath)) { | |
final Iterator<Path> iterator = ds.iterator(); | |
while (iterator.hasNext()) { | |
list.add(iterator.next()); | |
} | |
} | |
return list; | |
} | |
/** | |
* Lists all entries in the given directory. | |
* | |
* @param dirName | |
* directory path. | |
* @return a list of dir entries if an I/O error occurs | |
* @throws IOException | |
* an I/O error occurs accessing the file system | |
*/ | |
public List<Path> list(final String dirName) throws IOException { | |
return list(fileSystem.getPath(dirName)); | |
} | |
/** | |
* Lists all modules. | |
* | |
* @return a list of modules | |
* @throws IOException | |
* an I/O error occurs accessing the file system | |
*/ | |
public List<Path> modules() throws IOException { | |
return list(MODULES_PATH); | |
} | |
/** | |
* Lists all packages. | |
* | |
* @return a list of modules | |
* @throws IOException | |
* an I/O error occurs accessing the file system | |
*/ | |
public List<Path> packages() throws IOException { | |
return list(PACKAGES_PATH); | |
} | |
public FileSystem getFileSystem() { | |
return fileSystem; | |
} | |
} |