DeepCopy.java

package org.openstack.atlas.service.domain.util;

import java.io.*;

/**
 * Utility for making deep copies (vs. clone()'s shallow copies) of
 * objects. Objects are first serialized and then deserialized. Error
 * checking is fairly minimal in this implementation. If an object is
 * encountered that cannot be serialized (or that references an object
 * that cannot be serialized) an error is printed to System.err and
 * null is returned. Depending on your specific application, it might
 * make more sense to have copy(...) re-throw the exception.
 * <p/>
 * A later version of this class includes some minor optimizations.
 */
public class DeepCopy {

    /**
     * Returns a copy of the object, or null if the object cannot
     * be serialized.
     */
    public static Object copy(Object orig) {
        Object copy = null;
        try {
            // Write the object out to a byte array
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            ObjectOutputStream out = new ObjectOutputStream(bos);
            out.writeObject(orig);
            out.flush();
            out.close();

            // Make an input stream from the byte array and read
            // a copy of the object back in.
            ObjectInputStream in = new ObjectInputStream(
                    new ByteArrayInputStream(bos.toByteArray()));
            copy = in.readObject();
            in.close();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException cnfe) {
            cnfe.printStackTrace();
        }
        return copy;
    }

}