ClassVersionInfo.java Source code

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Here is the source code for ClassVersionInfo.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.ObjectStreamClass;
import java.io.Serializable;
import java.net.URL;
import java.security.CodeSource;

/**
 * Encapsulates a class serialVersionUID and codebase.
 * 
 * @author Scott.Stark@jboss.org
 * @version $Revision: 81038 $
 */
public 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);
    }
}