/*
 * Copyright (c) 2001-2008 Caucho Technology, Inc.  All rights reserved.
 *
 * The Apache Software License, Version 1.1
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Caucho Technology (http://www.caucho.com/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "Hessian", "Resin", and "Caucho" must not be used to
 *    endorse or promote products derived from this software without prior
 *    written permission. For written permission, please contact
 *    info@caucho.com.
 *
 * 5. Products derived from this software may not be called "Resin"
 *    nor may "Resin" appear in their names without prior written
 *    permission of Caucho Technology.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL CAUCHO TECHNOLOGY OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @author Scott Ferguson
 */

package com.caucho.hessian.micro;

import java.io.IOException;
import java.io.OutputStream;
import java.util.Date;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Vector;

Output stream for Hessian requests, compatible with microedition Java. It only uses classes and types available to J2ME. In particular, it does not have any support for the <double> type.

MicroHessianOutput does not depend on any classes other than in J2ME, so it can be extracted independently into a smaller package.

MicroHessianOutput is unbuffered, so any client needs to provide its own buffering.

OutputStream os = ...; // from http connection
MicroHessianOutput out = new MicroHessianOutput(os);
String value;
out.startCall("hello");  // start hello call
out.writeString("arg1"); // write a string argument
out.completeCall();      // complete the call
/** * Output stream for Hessian requests, compatible with microedition * Java. It only uses classes and types available to J2ME. In * particular, it does not have any support for the &lt;double> type. * * <p>MicroHessianOutput does not depend on any classes other than * in J2ME, so it can be extracted independently into a smaller package. * * <p>MicroHessianOutput is unbuffered, so any client needs to provide * its own buffering. * * <pre> * OutputStream os = ...; // from http connection * MicroHessianOutput out = new MicroHessianOutput(os); * String value; * * out.startCall("hello"); // start hello call * out.writeString("arg1"); // write a string argument * out.completeCall(); // complete the call * </pre> */
public class MicroHessianOutput { protected OutputStream os;
Creates a new Hessian output stream, initialized with an underlying output stream.
Params:
  • os – the underlying output stream.
/** * Creates a new Hessian output stream, initialized with an * underlying output stream. * * @param os the underlying output stream. */
public MicroHessianOutput(OutputStream os) { init(os); }
Creates an uninitialized Hessian output stream.
/** * Creates an uninitialized Hessian output stream. */
public MicroHessianOutput() { } public void init(OutputStream os) { this.os = os; }
Writes the method call:
c major minor
m b16 b8 method-namek
Params:
  • method – the method name to call.
/** * Writes the method call: * * <code><pre> * c major minor * m b16 b8 method-namek * </pre></code> * * @param method the method name to call. */
public void startCall(String method) throws IOException { os.write('c'); os.write(0); os.write(1); os.write('m'); int len = method.length(); os.write(len >> 8); os.write(len); printString(method, 0, len); }
Writes the method call:
z
/** * Writes the method call: * * <code><pre> * z * </pre></code> */
public void completeCall() throws IOException { os.write('z'); }
Writes a boolean value to the stream. The boolean will be written with the following syntax:
T
F
Params:
  • value – the boolean value to write.
/** * Writes a boolean value to the stream. The boolean will be written * with the following syntax: * * <code><pre> * T * F * </pre></code> * * @param value the boolean value to write. */
public void writeBoolean(boolean value) throws IOException { if (value) os.write('T'); else os.write('F'); }
Writes an integer value to the stream. The integer will be written with the following syntax:
I b32 b24 b16 b8
Params:
  • value – the integer value to write.
/** * Writes an integer value to the stream. The integer will be written * with the following syntax: * * <code><pre> * I b32 b24 b16 b8 * </pre></code> * * @param value the integer value to write. */
public void writeInt(int value) throws IOException { os.write('I'); os.write(value >> 24); os.write(value >> 16); os.write(value >> 8); os.write(value); }
Writes a long value to the stream. The long will be written with the following syntax:
L b64 b56 b48 b40 b32 b24 b16 b8
Params:
  • value – the long value to write.
/** * Writes a long value to the stream. The long will be written * with the following syntax: * * <code><pre> * L b64 b56 b48 b40 b32 b24 b16 b8 * </pre></code> * * @param value the long value to write. */
public void writeLong(long value) throws IOException { os.write('L'); os.write((byte) (value >> 56)); os.write((byte) (value >> 48)); os.write((byte) (value >> 40)); os.write((byte) (value >> 32)); os.write((byte) (value >> 24)); os.write((byte) (value >> 16)); os.write((byte) (value >> 8)); os.write((byte) (value)); }
Writes a date to the stream.
T  b64 b56 b48 b40 b32 b24 b16 b8
Params:
  • time – the date in milliseconds from the epoch in UTC
/** * Writes a date to the stream. * * <code><pre> * T b64 b56 b48 b40 b32 b24 b16 b8 * </pre></code> * * @param time the date in milliseconds from the epoch in UTC */
public void writeUTCDate(long time) throws IOException { os.write('d'); os.write((byte) (time >> 56)); os.write((byte) (time >> 48)); os.write((byte) (time >> 40)); os.write((byte) (time >> 32)); os.write((byte) (time >> 24)); os.write((byte) (time >> 16)); os.write((byte) (time >> 8)); os.write((byte) (time)); }
Writes a null value to the stream. The null will be written with the following syntax
N
Params:
  • value – the string value to write.
/** * Writes a null value to the stream. * The null will be written with the following syntax * * <code><pre> * N * </pre></code> * * @param value the string value to write. */
public void writeNull() throws IOException { os.write('N'); }
Writes a string value to the stream using UTF-8 encoding. The string will be written with the following syntax:
S b16 b8 string-value
If the value is null, it will be written as
N
Params:
  • value – the string value to write.
/** * Writes a string value to the stream using UTF-8 encoding. * The string will be written with the following syntax: * * <code><pre> * S b16 b8 string-value * </pre></code> * * If the value is null, it will be written as * * <code><pre> * N * </pre></code> * * @param value the string value to write. */
public void writeString(String value) throws IOException { if (value == null) { os.write('N'); } else { int len = value.length(); os.write('S'); os.write(len >> 8); os.write(len); printString(value); } }
Writes a byte array to the stream. The array will be written with the following syntax:
B b16 b18 bytes
If the value is null, it will be written as
N
Params:
  • value – the string value to write.
/** * Writes a byte array to the stream. * The array will be written with the following syntax: * * <code><pre> * B b16 b18 bytes * </pre></code> * * If the value is null, it will be written as * * <code><pre> * N * </pre></code> * * @param value the string value to write. */
public void writeBytes(byte []buffer) throws IOException { if (buffer == null) os.write('N'); else writeBytes(buffer, 0, buffer.length); }
Writes a byte array to the stream. The array will be written with the following syntax:
B b16 b18 bytes
If the value is null, it will be written as
N
Params:
  • value – the string value to write.
/** * Writes a byte array to the stream. * The array will be written with the following syntax: * * <code><pre> * B b16 b18 bytes * </pre></code> * * If the value is null, it will be written as * * <code><pre> * N * </pre></code> * * @param value the string value to write. */
public void writeBytes(byte []buffer, int offset, int length) throws IOException { if (buffer == null) { os.write('N'); } else { os.write('B'); os.write(length << 8); os.write(length); os.write(buffer, offset, length); } }
Writes a reference.
R b32 b24 b16 b8
Params:
  • value – the integer value to write.
/** * Writes a reference. * * <code><pre> * R b32 b24 b16 b8 * </pre></code> * * @param value the integer value to write. */
public void writeRef(int value) throws IOException { os.write('R'); os.write(value << 24); os.write(value << 16); os.write(value << 8); os.write(value); }
Writes a generic object to the output stream.
/** * Writes a generic object to the output stream. */
public void writeObject(Object object) throws IOException { if (object == null) writeNull(); else if (object instanceof String) writeString((String) object); else if (object instanceof Boolean) writeBoolean(((Boolean) object).booleanValue()); else if (object instanceof Integer) writeInt(((Integer) object).intValue()); else if (object instanceof Long) writeLong(((Long) object).longValue()); else if (object instanceof Date) writeUTCDate(((Date) object).getTime()); else if (object instanceof byte[]) { byte []data = (byte []) object; writeBytes(data, 0, data.length); } else if (object instanceof Vector) { Vector vector = (Vector) object; int size = vector.size(); writeListBegin(size, null); for (int i = 0; i < size; i++) writeObject(vector.elementAt(i)); writeListEnd(); } else if (object instanceof Hashtable) { Hashtable hashtable = (Hashtable) object; writeMapBegin(null); Enumeration e = hashtable.keys(); while (e.hasMoreElements()) { Object key = e.nextElement(); Object value = hashtable.get(key); writeObject(key); writeObject(value); } writeMapEnd(); } else writeCustomObject(object); }
Applications which override this can do custom serialization.
Params:
  • object – the object to write.
/** * Applications which override this can do custom serialization. * * @param object the object to write. */
public void writeCustomObject(Object object) throws IOException { throw new IOException("unexpected object: " + object); }
Writes the list header to the stream. List writers will call writeListBegin followed by the list contents and then call writeListEnd.
<list>
  <type>java.util.ArrayList</type>
  <length>3</length>
  <int>1</int>
  <int>2</int>
  <int>3</int>
</list>
/** * Writes the list header to the stream. List writers will call * <code>writeListBegin</code> followed by the list contents and then * call <code>writeListEnd</code>. * * <code><pre> * &lt;list> * &lt;type>java.util.ArrayList&lt;/type> * &lt;length>3&lt;/length> * &lt;int>1&lt;/int> * &lt;int>2&lt;/int> * &lt;int>3&lt;/int> * &lt;/list> * </pre></code> */
public void writeListBegin(int length, String type) throws IOException { os.write('V'); os.write('t'); printLenString(type); os.write('l'); os.write(length >> 24); os.write(length >> 16); os.write(length >> 8); os.write(length); }
Writes the tail of the list to the stream.
/** * Writes the tail of the list to the stream. */
public void writeListEnd() throws IOException { os.write('z'); }
Writes the map header to the stream. Map writers will call writeMapBegin followed by the map contents and then call writeMapEnd.
Mt b16 b8 type ( )z
/** * Writes the map header to the stream. Map writers will call * <code>writeMapBegin</code> followed by the map contents and then * call <code>writeMapEnd</code>. * * <code><pre> * Mt b16 b8 type (<key> <value>)z * </pre></code> */
public void writeMapBegin(String type) throws IOException { os.write('M'); os.write('t'); printLenString(type); }
Writes the tail of the map to the stream.
/** * Writes the tail of the map to the stream. */
public void writeMapEnd() throws IOException { os.write('z'); }
Writes a remote object reference to the stream. The type is the type of the remote interface.
'r' 't' b16 b8 type url
/** * Writes a remote object reference to the stream. The type is the * type of the remote interface. * * <code><pre> * 'r' 't' b16 b8 type url * </pre></code> */
public void writeRemote(String type, String url) throws IOException { os.write('r'); os.write('t'); printLenString(type); os.write('S'); printLenString(url); }
Prints a string to the stream, encoded as UTF-8 with preceeding length
Params:
  • v – the string to print.
/** * Prints a string to the stream, encoded as UTF-8 with preceeding length * * @param v the string to print. */
public void printLenString(String v) throws IOException { if (v == null) { os.write(0); os.write(0); } else { int len = v.length(); os.write(len >> 8); os.write(len); printString(v, 0, len); } }
Prints a string to the stream, encoded as UTF-8
Params:
  • v – the string to print.
/** * Prints a string to the stream, encoded as UTF-8 * * @param v the string to print. */
public void printString(String v) throws IOException { printString(v, 0, v.length()); }
Prints a string to the stream, encoded as UTF-8
Params:
  • v – the string to print.
/** * Prints a string to the stream, encoded as UTF-8 * * @param v the string to print. */
public void printString(String v, int offset, int length) throws IOException { for (int i = 0; i < length; i++) { char ch = v.charAt(i + offset); if (ch < 0x80) os.write(ch); else if (ch < 0x800) { os.write(0xc0 + ((ch >> 6) & 0x1f)); os.write(0x80 + (ch & 0x3f)); } else { os.write(0xe0 + ((ch >> 12) & 0xf)); os.write(0x80 + ((ch >> 6) & 0x3f)); os.write(0x80 + (ch & 0x3f)); } } } }