org.osgi.service.indexer.impl.JarResource Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of c8tech.tools.maven.library.osgi.repoindex Show documentation
An OSGi bundle library providing a repository indexer service based on the OSGi Alliance BIndex tool.
There is a newer version: 0.9.0
Show newest version
/**
 * ==========================================================================
 * Copyright © 2015-2018 OSGi Alliance, Cristiano Gavião.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 * Cristiano Gavião ([email protected])- initial API and implementation
 * ==========================================================================
 */
package org.osgi.service.indexer.impl;

/*
 * Part of this code was borrowed from BIndex project (https://github.com/osgi/bindex) 
 * and it is released under OSGi Specification License, VERSION 2.0
 */
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Dictionary;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.jar.Manifest;

import org.osgi.service.indexer.Constants;
import org.osgi.service.indexer.Resource;

public class JarResource implements Resource {

    private final File file;
    private final JarFile jarFile;
    private final String ilocation;

    private final Dictionary properties = new Hashtable<>(); // NOSONAR

    private final Map> prefixMap = new HashMap<>();
    private final Map paths = new HashMap<>();

    private Manifest manifest;

    public JarResource(File file) throws IOException {
        this.file = file;

        this.ilocation = file.getPath();
        this.jarFile = new JarFile(file);

        properties.put(Constants.NAME, file.getName());
        properties.put(Constants.LOCATION, ilocation);
        properties.put(Constants.SIZE, file.length());
        properties.put(Constants.LAST_MODIFIED, file.lastModified());

        Enumeration entries = jarFile.entries();
        while (entries.hasMoreElements()) {
            JarEntry entry = entries.nextElement();

            String path = entry.getName();
            paths.put(path, entry);

            String parentPath = getParentPath(path);

            List list = getOrCreatePrefix(parentPath);
            list.add(entry);
        }
    }

    private static String getParentPath(String path) {
        int index;
        if (path.endsWith("/")) {
            index = path.substring(0, path.length() - 1).lastIndexOf('/');
        } else {
            index = path.lastIndexOf('/');
        }

        String parentPath;
        if (index == -1)
            parentPath = "";
        else
            parentPath = path.substring(0, index + 1);
        return parentPath;
    }

    private synchronized List getOrCreatePrefix(String prefix) {
        return prefixMap.computeIfAbsent(prefix,
                k -> new LinkedList());
    }

    @Override
    public String getLocation() {
        return ilocation;
    }

    @Override
    public Dictionary getProperties() {
        return properties;
    }

    @Override
    public long getSize() {
        return file.length();
    }

    @Override
    public InputStream getStream() throws IOException {
        return new FileInputStream(file);
    }

    @Override
    public Manifest getManifest() throws IOException {
        synchronized (this) {
            if (manifest == null) {
                Resource manifestResource = getChild("META-INF/MANIFEST.MF");
                if (manifestResource != null) {
                    try {
                        manifest = new Manifest(manifestResource.getStream());
                    } finally {
                        manifestResource.close();
                    }
                }
            }
            return manifest;
        }
    }

    @Override
    public List listChildren(String prefix) throws IOException {
        List entries = prefixMap.get(prefix);
        if (entries == null)
            return null; // NOSONAR

        List result = new ArrayList<>(entries.size());
        for (JarEntry entry : entries) {
            String unprefixedPath = entry.getName().substring(prefix.length());
            result.add(unprefixedPath);
        }
        return result;
    }

    @Override
    public Resource getChild(String path) throws IOException {
        String childLocation = getLocation() + "#" + path;

        JarEntry entry = paths.get(path);
        if (entry != null) {
            return new FlatStreamResource(path, childLocation,
                    jarFile.getInputStream(entry));
        }
        return null;
    }

    @Override
    public void close() {
        try {
            jarFile.close();
        } catch (IOException e) {
            // Don't care
        }
    }

}