001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.vfs2.provider.jar;
018
019import java.util.ArrayList;
020import java.util.Arrays;
021import java.util.Collection;
022import java.util.Collections;
023
024import org.apache.commons.vfs2.Capability;
025import org.apache.commons.vfs2.FileName;
026import org.apache.commons.vfs2.FileObject;
027import org.apache.commons.vfs2.FileSystem;
028import org.apache.commons.vfs2.FileSystemException;
029import org.apache.commons.vfs2.FileSystemOptions;
030import org.apache.commons.vfs2.FileType;
031import org.apache.commons.vfs2.provider.AbstractFileName;
032import org.apache.commons.vfs2.provider.LayeredFileName;
033import org.apache.commons.vfs2.provider.zip.ZipFileProvider;
034
035/**
036 * A file system provider for Jar files. Provides read-only file systems. This provides access to Jar specific features
037 * like Signing and Manifest Attributes.
038 */
039public class JarFileProvider extends ZipFileProvider {
040
041    static final Collection<Capability> CAPABILITIES;
042
043    static {
044        final Collection<Capability> combined = new ArrayList<>(capabilities);
045        combined.addAll(Arrays.asList(Capability.ATTRIBUTES, Capability.FS_ATTRIBUTES, Capability.SIGNING,
046                Capability.MANIFEST_ATTRIBUTES, Capability.VIRTUAL));
047        CAPABILITIES = Collections.unmodifiableCollection(combined);
048    }
049
050    /**
051     * Constructs a new instance.
052     */
053    public JarFileProvider() {
054    }
055
056    /**
057     * Creates a layered file system. This method is called if the file system is not cached.
058     *
059     * @param scheme The URI scheme.
060     * @param file The file to create the file system on top of.
061     * @return The file system.
062     */
063    @Override
064    protected FileSystem doCreateFileSystem(final String scheme, final FileObject file,
065            final FileSystemOptions fileSystemOptions) throws FileSystemException {
066        final AbstractFileName name = new LayeredFileName(scheme, file.getName(), FileName.ROOT_PATH, FileType.FOLDER);
067        return new JarFileSystem(name, file, fileSystemOptions);
068    }
069
070    @Override
071    public Collection<Capability> getCapabilities() {
072        return CAPABILITIES;
073    }
074}