SerialVersionUID.java Source code

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Here is the source code for SerialVersionUID.java

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/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2008, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamClass;
import java.io.Serializable;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
import java.security.CodeSource;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.TreeMap;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * A tool/service that computes all the class serialVersionUIDs under the jboss
 * home directory.
 * 
 * @author Scott.Stark@jboss.org
 * @author Dimitris.Andreadis@jboss.org
 * @version $Revision: 84164 $
 */
public class SerialVersionUID {
    /** A jdk logger so that only this + ClassVersionInfo are needed */
    static Logger log = Logger.getLogger("SerialVersionUID");

    static void buildJarSet(File dir, HashSet jarFiles) throws MalformedURLException {
        File[] files = dir.listFiles();
        int count = files != null ? files.length : 0;
        System.out.println("Checking dir: " + dir + ", count=" + count);
        for (int n = 0; n < count; n++) {
            File child = files[n];
            // Ignore the server tmp directory
            if (child.isDirectory() && child.getName().equals("tmp") == false)
                buildJarSet(child, jarFiles);
            else if (child.getName().endsWith(".jar"))
                jarFiles.add(child.toURL());
        }
    }

    /**
     * Build a TreeMap of the class name to ClassVersionInfo
     * 
     * @param jar
     * @param classVersionMap
     *          TreeMap<String, ClassVersionInfo> for serializable classes
     * @param cl -
     *          the class loader to use
     * @throws IOException
     *           thrown if the jar cannot be opened
     */
    static void generateJarSerialVersionUIDs(URL jar, TreeMap classVersionMap, ClassLoader cl, String pkgPrefix)
            throws IOException {
        String jarName = jar.getFile();
        JarFile jf = new JarFile(jarName);
        Enumeration entries = jf.entries();
        while (entries.hasMoreElements()) {
            JarEntry entry = (JarEntry) entries.nextElement();
            String name = entry.getName();
            if (name.endsWith(".class") && name.startsWith(pkgPrefix)) {
                name = name.substring(0, name.length() - 6);
                String classname = name.replace('/', '.');
                try {
                    log.fine("Creating ClassVersionInfo for: " + classname);
                    ClassVersionInfo cvi = new ClassVersionInfo(classname, cl);
                    log.fine(cvi.toString());
                    if (cvi.getSerialVersion() != 0) {
                        ClassVersionInfo prevCVI = (ClassVersionInfo) classVersionMap.put(classname, cvi);
                        if (prevCVI != null) {
                            if (prevCVI.getSerialVersion() != cvi.getSerialVersion()) {
                                log.severe("Found inconsistent classes, " + prevCVI + " != " + cvi + ", jar: "
                                        + jarName);
                            }
                        }
                        if (cvi.getHasExplicitSerialVersionUID() == false) {
                            log.warning("No explicit serialVersionUID: " + cvi);
                        }
                    }
                } catch (OutOfMemoryError e) {
                    log.log(Level.SEVERE, "Check the MaxPermSize", e);
                } catch (Throwable e) {
                    log.log(Level.FINE, "While loading: " + name, e);
                }
            }
        }
        jf.close();
    }

    /**
     * Create a Map<String, ClassVersionInfo> for the jboss dist jars.
     * 
     * @param jbossHome -
     *          the jboss dist root directory
     * @return Map<String, ClassVersionInfo>
     * @throws IOException
     */
    public static Map generateJBossSerialVersionUIDReport(File jbossHome) throws IOException {
        // Obtain the jars from the /lib, common/ and /server/all locations
        HashSet jarFiles = new HashSet();
        File lib = new File(jbossHome, "lib");
        buildJarSet(lib, jarFiles);
        File common = new File(jbossHome, "common");
        buildJarSet(common, jarFiles);
        File all = new File(jbossHome, "server/all");
        buildJarSet(all, jarFiles);
        URL[] cp = new URL[jarFiles.size()];
        jarFiles.toArray(cp);
        ClassLoader parent = Thread.currentThread().getContextClassLoader();
        URLClassLoader completeClasspath = new URLClassLoader(cp, parent);

        TreeMap classVersionMap = new TreeMap();
        Iterator jarIter = jarFiles.iterator();
        while (jarIter.hasNext()) {
            URL jar = (URL) jarIter.next();
            try {
                generateJarSerialVersionUIDs(jar, classVersionMap, completeClasspath, "");
            } catch (IOException e) {
                log.info("Failed to process jar: " + jar);
            }
        }

        return classVersionMap;
    }

    /**
     * Create a Map<String, ClassVersionInfo> for the jboss dist jars.
     * 
     * @param j2eeHome -
     *          the j2ee ri dist root directory
     * @return Map<String, ClassVersionInfo>
     * @throws IOException
     */
    public static Map generateRISerialVersionUIDReport(File j2eeHome) throws IOException {
        // Obtain the jars from the /lib
        HashSet jarFiles = new HashSet();
        File lib = new File(j2eeHome, "lib");
        buildJarSet(lib, jarFiles);
        URL[] cp = new URL[jarFiles.size()];
        jarFiles.toArray(cp);
        ClassLoader parent = Thread.currentThread().getContextClassLoader();
        URLClassLoader completeClasspath = new URLClassLoader(cp, parent);

        TreeMap classVersionMap = new TreeMap();
        Iterator jarIter = jarFiles.iterator();
        while (jarIter.hasNext()) {
            URL jar = (URL) jarIter.next();
            try {
                generateJarSerialVersionUIDs(jar, classVersionMap, completeClasspath, "javax");
            } catch (IOException e) {
                log.info("Failed to process jar: " + jar);
            }
        }

        return classVersionMap;
    }

    /**
     * Generate a mapping of the serial version UIDs for the serializable classes
     * under the jboss dist directory
     * 
     * @param args -
     *          [0] = jboss dist root directory
     * @throws Exception
     */
    public static void main(String[] args) throws Exception {
        if (args.length != 1) {
            System.err.println("Usage: jboss-home | -rihome ri-home");
            System.exit(1);
        }
        File distHome = new File(args[0]);
        Map classVersionMap = null;
        if (args.length == 2)
            classVersionMap = generateRISerialVersionUIDReport(distHome);
        else
            classVersionMap = generateJBossSerialVersionUIDReport(distHome);
        // Write the map out the object file
        log.info("Total classes with serialVersionUID != 0: " + classVersionMap.size());
        FileOutputStream fos = new FileOutputStream("serialuid.ser");
        ObjectOutputStream oos = new ObjectOutputStream(fos);
        oos.writeObject(classVersionMap);
        fos.close();
    }
}

/**
 * Encapsulates a class serialVersionUID and codebase.
 * 
 * @author Scott.Stark@jboss.org
 * @version $Revision: 81038 $
 */
class ClassVersionInfo implements Serializable {
    static final long serialVersionUID = 2036506209171911437L;

    /** The named class serialVersionUID as returned by ObjectStreamClass */
    private long serialVersion;

    /** The binary class name */
    private String name;

    private boolean hasExplicitSerialVersionUID;

    private transient URL location;

    public ClassVersionInfo(String name, ClassLoader loader) throws ClassNotFoundException {
        this.name = name;
        Class c = loader.loadClass(name);
        CodeSource cs = c.getProtectionDomain().getCodeSource();
        if (cs != null)
            location = cs.getLocation();
        if (c.isInterface() == false) {
            ObjectStreamClass osc = ObjectStreamClass.lookup(c);
            if (osc != null) {
                serialVersion = osc.getSerialVersionUID();
                try {
                    c.getDeclaredField("serialVersionUID");
                    hasExplicitSerialVersionUID = true;
                } catch (NoSuchFieldException e) {
                    hasExplicitSerialVersionUID = false;
                }
            }
        }
    }

    public long getSerialVersion() {
        return serialVersion;
    }

    public boolean getHasExplicitSerialVersionUID() {
        return hasExplicitSerialVersionUID;
    }

    public String getName() {
        return name;
    }

    public String toString() {
        StringBuffer tmp = new StringBuffer("ClassVersionInfo");
        tmp.append('{');
        tmp.append("serialVersion=");
        tmp.append(serialVersion);
        tmp.append(", hasExplicitSerialVersionUID=");
        tmp.append(hasExplicitSerialVersionUID);
        tmp.append(", name=");
        tmp.append(name);
        tmp.append(", location=");
        tmp.append(location);
        tmp.append('}');
        return tmp.toString();
    }

    /**
     * Usage: ClassVersionInfo class-name
     * 
     * Locate the class name on the thread context class loader classpath and
     * print its version info.
     * 
     * @param args
     *          [0] = class-name
     */
    public static void main(String[] args) throws Exception {
        if (args.length == 0)
            throw new IllegalStateException("Usage: ...ClassVersionInfo class-name");
        ClassLoader loader = Thread.currentThread().getContextClassLoader();
        ClassVersionInfo info = new ClassVersionInfo(args[0], loader);
        System.out.println(info);
    }
}