/* * %W% %E% * * Copyright  1990-2006 Sun Microsystems, Inc. All Rights Reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER *  * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License version * 2 only, as published by the Free Software Foundation.  *  * 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 * General Public License version 2 for more details (a copy is * included at /legal/license.txt).  *  * You should have received a copy of the GNU General Public License * version 2 along with this work; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA  *  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa * Clara, CA 95054 or visit www.sun.com if you need additional * information or have any questions.  */package com.sun.jump.message;import java.io.IOException;/** * <code>JUMPMessageReader</code> is used to read data from a message. */public class JUMPMessageReader {    private final byte[] messageDataBytes;    private final int messageMarkOffset;    int messageDataOffset;  // Package private access for JUMPMessage    /**     * Creates a new instance of JUMPMessageReader for message m     */    public JUMPMessageReader(JUMPMessage m) {	this(m, m.messageUserDataOffset);    }        /**     * Package private constructor to set initial offset to     * start reading from.     */    JUMPMessageReader(JUMPMessage m, int offset) {	this.messageDataBytes    = m.messageDataBytes;	// Context starts from user data offset, past the header	this.messageMarkOffset   = offset;	this.messageDataOffset   = offset;    }        public int getInt() {	// Get int at messageDataOffset	int b1 = messageDataBytes[messageDataOffset]   & 0xff;	int b2 = messageDataBytes[messageDataOffset+1] & 0xff;	int b3 = messageDataBytes[messageDataOffset+2] & 0xff;	int b4 = messageDataBytes[messageDataOffset+3] & 0xff;	int i = (b1 << 24) + (b2 << 16) + (b3 << 8) + b4;	if (false) {	    System.err.println("Decoded int "+i+" from ["+			       b1+", "+b2+", "+b3+", "+b4+"]");	}	messageDataOffset += 4;	return i;    }    public long getLong() {        long l = (((long)messageDataBytes[messageDataOffset+0] << 56) +		  ((long)(messageDataBytes[messageDataOffset+1] & 255) << 48) +		  ((long)(messageDataBytes[messageDataOffset+2] & 255) << 40) +		  ((long)(messageDataBytes[messageDataOffset+3] & 255) << 32) +		  ((long)(messageDataBytes[messageDataOffset+4] & 255) << 24) +		  ((messageDataBytes[messageDataOffset+5] & 255) << 16) +		  ((messageDataBytes[messageDataOffset+6] & 255) <<  8) +		  ((messageDataBytes[messageDataOffset+7] & 255) <<  0));	messageDataOffset += 8;	return l;    }    public byte getByte() {	byte b = messageDataBytes[messageDataOffset];	messageDataOffset += 1;	return b;    }    private char[] fromBytes(byte[] ascii)     {	int n = ascii.length;        char[] value = new char[n-1]; // Leave out the null termination	for (int i = 0; i < n-1; i++) {	    value[i] = (char) (ascii[i] & 0xff);	}	return value;    }        public String getUTF() {	// FIXME: GEt string in Java-modified utf-8	// Re-use implementation in DataInputStream.readUTF().	return new String(fromBytes(getByteArray()));    }    public byte[] getByteArray() {	int len = getInt();	if (len == -1) {	    return null;	}	byte[] b = new byte[len];	System.arraycopy(messageDataBytes, messageDataOffset, b, 0, len);	messageDataOffset += len;	return b;    }    public String[] getUTFArray() {	int len = getInt();	if (len == -1) {	    return null;	}	String[] s = new String[len];	for (int i = 0; i < len; i++) {	    s[i] = getUTF();	}	return s;    }    public void reset() {	messageDataOffset = messageMarkOffset;    }}