messageoutputstream.java

aglet的部分源码

package com.ibm.aglets;

/*
 * @(#)MessageOutputStream.java
 * 
 * IBM Confidential-Restricted
 * 
 * OCO Source Materials
 * 
 * 03L7246 (c) Copyright IBM Corp. 1996, 1998
 * 
 * The source code for this program is not published or otherwise
 * divested of its trade secrets, irrespective of what has been
 * deposited with the U.S. Copyright Office.
 */

import java.io.ByteArrayOutputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.io.IOException;

/**
 * @see MessageInputStream
 */
final class MessageOutputStream extends ObjectOutputStream {

	private ResourceManager rm = null;

	/**
	 * Create a new instance of this class with version given.
	 * @param out an output stream where data are written into.
	 * @exception IOException if can not write into the output stream.
	 */
	MessageOutputStream(OutputStream out, 
						ResourceManager rm) throws IOException {
		super(out);
		this.rm = rm;
	}
	/**
	 * Write the class data into the output stream. Class data of all super
	 * classes of the class will be written together.
	 * @param cl class.
	 * @exception IOException if can not write into the output stream.
	 */
	synchronized public void annotateClass(Class cls) throws IOException {
		ClassLoader loader = cls.getClassLoader();

		if (loader != null && (loader instanceof ResourceManager) 
				&& (rm == null || rm.contains(cls) == false)) {
			throw new AgletsSecurityException(cls.getName());
		} 
	}
	static byte[] toByteArray(ResourceManager rm, 
							  Object obj) throws IOException {
		ByteArrayOutputStream out = new ByteArrayOutputStream();
		MessageOutputStream mos = new MessageOutputStream(out, rm);

		mos.writeObject(obj);
		return out.toByteArray();
	}
}