framework/src/main/java/org/apache/felix/framework/cache/DirectoryRevision.java

/*
 * 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.felix.framework.cache;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.jar.Manifest;

import org.apache.felix.framework.Logger;
import org.apache.felix.framework.util.FelixConstants;
import org.apache.felix.framework.util.StringMap;
import org.apache.felix.framework.util.manifestparser.ManifestParser;
import org.apache.felix.moduleloader.DirectoryContent;
import org.apache.felix.moduleloader.IContent;
import org.apache.felix.moduleloader.JarContent;

/**
 * <p>
 * This class implements a bundle archive revision for exploded bundle
 * JAR files. It uses the specified location directory "in-place" to
 * execute the bundle and does not copy the bundle content at all.
 * </p>
**/
class DirectoryRevision extends BundleRevision
{
    private static final transient String BUNDLE_JAR_FILE = "bundle.jar";

    private File m_refDir = null;
    private Map m_header = null;

    public DirectoryRevision(
        Logger logger, File revisionRootDir, String location) throws Exception
    {
        super(logger, revisionRootDir, location);
        m_refDir = new File(location.substring(
            location.indexOf(BundleArchive.FILE_PROTOCOL)
                + BundleArchive.FILE_PROTOCOL.length()));

        // If the revision directory exists, then we don't
        // need to initialize since it has already been done.
        if (BundleCache.getSecureAction().fileExists(this.getRevisionRootDir()))
        {
            return;
        }

        // Create revision directory, we only need this to store the
        // revision location, since nothing else needs to be extracted
        // since we are referencing a read directory already.
        if (!BundleCache.getSecureAction().mkdir(this.getRevisionRootDir()))
        {
            this.getLogger().log(
                Logger.LOG_ERROR,
                this.getClass().getName() + ": Unable to create revision directory.");
            throw new IOException("Unable to create archive directory.");
        }
    }

    public synchronized Map getManifestHeader()
        throws Exception
    {
        if (m_header != null)
        {
            return m_header;
        }

        // Read the header file from the reference directory.
        InputStream is = null;

        try
        {
            // Open manifest file.
            is = BundleCache.getSecureAction()
                .getFileInputStream(new File(m_refDir, "META-INF/MANIFEST.MF"));
            // Error if no jar file.
            if (is == null)
            {
                throw new IOException("No manifest file found.");
            }

            // Get manifest.
            Manifest mf = new Manifest(is);
            // Create a case insensitive map of manifest attributes.
            m_header = new StringMap(mf.getMainAttributes(), false);
            return m_header;
        }
        finally
        {
            if (is != null) is.close();
        }
    }

    public IContent getContent() throws Exception
    {
        return new DirectoryContent(m_refDir);
    }

    public synchronized IContent[] getContentPath() throws Exception
    {
        // Creating the content path entails examining the bundle's
        // class path to determine whether the bundle JAR file itself
        // is on the bundle's class path and then creating content
        // objects for everything on the class path.

        // Get the bundle's manifest header.
        Map map = this.getManifestHeader();

        // Find class path meta-data.
        String classPath = (map == null)
            ? null : (String) map.get(FelixConstants.BUNDLE_CLASSPATH);

        // Parse the class path into strings.
        String[] classPathStrings = ManifestParser.parseDelimitedString(
            classPath, FelixConstants.CLASS_PATH_SEPARATOR);

        if (classPathStrings == null)
        {
            classPathStrings = new String[0];
        }

        // Create the bundles class path.
        IContent self = new DirectoryContent(m_refDir);
        List contentList = new ArrayList();
        for (int i = 0; i < classPathStrings.length; i++)
        {
            if (classPathStrings[i].equals(FelixConstants.CLASS_PATH_DOT))
            {
                contentList.add(self);
            }
            else
            {
                // Determine if the class path entry is a file or directory.
                File file = new File(m_refDir, classPathStrings[i]);
                if (BundleCache.getSecureAction().isFileDirectory(file))
                {
                    contentList.add(new DirectoryContent(file));
                }
                else
                {
                    // Ignore any entries that do not exist per the spec.
                    if (BundleCache.getSecureAction().fileExists(file))
                    {
                        contentList.add(new JarContent(file));
                    }
                }
            }
        }

        // If there is nothing on the class path, then include
        // "." by default, as per the spec.
        if (contentList.size() == 0)
        {
            contentList.add(self);
        }

        return (IContent[]) contentList.toArray(new IContent[contentList.size()]);
    }

// TODO: This will need to consider security.
    public String findLibrary(String libName) throws Exception
    {
        return BundleCache.getSecureAction().getAbsolutePath(new File(this.m_refDir, libName));
    }

    public void dispose() throws Exception
    {
        // Nothing to dispose of, since we don't maintain any state outside
        // of the revision directory, which will be automatically deleted
        // by the parent bundle archive.
    }
}