org.bimserver.plugins.JarClassLoader.java Source code

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Here is the source code for org.bimserver.plugins.JarClassLoader.java

Source

package org.bimserver.plugins;

/******************************************************************************
 * Copyright (C) 2009-2012  BIMserver.org
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *****************************************************************************/

import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLStreamHandler;
import java.util.HashMap;
import java.util.Map;
import java.util.jar.JarEntry;
import java.util.jar.JarInputStream;

import org.apache.commons.io.IOUtils;
import org.apache.commons.io.output.ByteArrayOutputStream;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class JarClassLoader extends ClassLoader {
    private static final Logger LOGGER = LoggerFactory.getLogger(JarClassLoader.class);
    private File jarFile;
    private Map<String, byte[]> map;
    private Map<String, Class<?>> loadedClasses = new HashMap<String, Class<?>>();

    public JarClassLoader(ClassLoader parentClassLoader, File jarFile) {
        super(parentClassLoader);
        this.jarFile = jarFile;
        try {
            JarInputStream jarInputStream = new JarInputStream(new FileInputStream(jarFile));
            JarEntry entry = jarInputStream.getNextJarEntry();
            map = new HashMap<String, byte[]>();
            while (entry != null) {
                ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
                IOUtils.copy(jarInputStream, byteArrayOutputStream);
                map.put(entry.getName(), byteArrayOutputStream.toByteArray());
                if (entry.getName().endsWith(".jar")) {
                    loadSubJars(byteArrayOutputStream.toByteArray());
                }
                entry = jarInputStream.getNextJarEntry();
            }
            jarInputStream.close();
        } catch (FileNotFoundException e) {
        } catch (IOException e) {
        }
    }

    private void loadSubJars(byte[] byteArray) {
        try {
            JarInputStream jarInputStream = new JarInputStream(new ByteArrayInputStream(byteArray));
            JarEntry entry = jarInputStream.getNextJarEntry();
            while (entry != null) {
                ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
                IOUtils.copy(jarInputStream, byteArrayOutputStream);
                map.put(entry.getName(), byteArrayOutputStream.toByteArray());
                entry = jarInputStream.getNextJarEntry();
            }
            jarInputStream.close();
        } catch (IOException e) {
            LOGGER.error("", e);
        }
    }

    @Override
    protected URL findResource(final String name) {
        if (map.containsKey(name)) {
            try {
                return new URL(new URL("jar:" + jarFile.toURI().toURL() + "!/" + name), name,
                        new URLStreamHandler() {
                            @Override
                            protected URLConnection openConnection(URL u) throws IOException {
                                return new URLConnection(u) {
                                    @Override
                                    public void connect() throws IOException {
                                    }

                                    @Override
                                    public InputStream getInputStream() throws IOException {
                                        return new ByteArrayInputStream(map.get(name));
                                    }
                                };
                            }
                        });
            } catch (MalformedURLException e) {
                LOGGER.error("", e);
            }
        }
        return null;
    }

    @Override
    protected Class<?> findClass(String name) throws ClassNotFoundException {
        String fileName = name.replace(".", "/") + ".class";
        if (loadedClasses.containsKey(fileName)) {
            return loadedClasses.get(fileName);
        }
        if (map.containsKey(fileName)) {
            byte[] bs = map.get(fileName);
            Class<?> defineClass = defineClass(name, bs, 0, bs.length);
            loadedClasses.put(fileName, defineClass);

            /*
             * This is a fix to actually load the package-info.class file with
             * the annotations about for example namespaces required for JAXB to
             * work. Found this code here:
             * https://issues.jboss.org/browse/JBPM-1404
             */
            if (defineClass != null) {
                final int packageIndex = name.lastIndexOf('.');
                if (packageIndex != -1) {
                    final String packageName = name.substring(0, packageIndex);
                    final Package classPackage = getPackage(packageName);
                    if (classPackage == null) {
                        definePackage(packageName, null, null, null, null, null, null, null);
                    }
                }
            }
            return defineClass;
        }
        throw new ClassNotFoundException(name);
    }
}