/*
 * 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 "Burlap", "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.io;

import java.io.IOException;
import java.io.OutputStream;
import java.util.IdentityHashMap;

Output stream for Hessian requests, compatible with microedition Java. It only uses classes and types available in JDK.

Since HessianOutput does not depend on any classes other than in the JDK, it can be extracted independently into a smaller package.

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

OutputStream os = ...; // from http connection
HessianOutput out = new HessianOutput(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 in JDK. * * <p>Since HessianOutput does not depend on any classes other than * in the JDK, it can be extracted independently into a smaller package. * * <p>HessianOutput is unbuffered, so any client needs to provide * its own buffering. * * <pre> * OutputStream os = ...; // from http connection * HessianOutput out = new HessianOutput(os); * String value; * * out.startCall("hello"); // start hello call * out.writeString("arg1"); // write a string argument * out.completeCall(); // complete the call * </pre> */
public class HessianOutput extends AbstractHessianOutput { // the output stream/ protected OutputStream os; // map of references private IdentityHashMap _refs; private int _version = 1;
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 HessianOutput(OutputStream os) { init(os); }
Creates an uninitialized Hessian output stream.
/** * Creates an uninitialized Hessian output stream. */
public HessianOutput() { }
Initializes the output
/** * Initializes the output */
public void init(OutputStream os) { this.os = os; _refs = null; if (_serializerFactory == null) _serializerFactory = new SerializerFactory(); }
Sets the client's version.
/** * Sets the client's version. */
public void setVersion(int version) { _version = version; }
Writes a complete method call.
/** * Writes a complete method call. */
public void call(String method, Object []args) throws IOException { int length = args != null ? args.length : 0; startCall(method, length); for (int i = 0; i < length; i++) writeObject(args[i]); completeCall(); }
Starts the method call. Clients would use startCall instead of call if they wanted finer control over writing the arguments, or needed to write headers.
c major minor
m b16 b8 method-name
Params:
  • method – the method name to call.
/** * Starts the method call. Clients would use <code>startCall</code> * instead of <code>call</code> if they wanted finer control over * writing the arguments, or needed to write headers. * * <code><pre> * c major minor * m b16 b8 method-name * </pre></code> * * @param method the method name to call. */
public void startCall(String method, int length) throws IOException { os.write('c'); os.write(_version); os.write(0); os.write('m'); int len = method.length(); os.write(len >> 8); os.write(len); printString(method, 0, len); }
Writes the call tag. This would be followed by the headers and the method tag.
c major minor
Params:
  • method – the method name to call.
/** * Writes the call tag. This would be followed by the * headers and the method tag. * * <code><pre> * c major minor * </pre></code> * * @param method the method name to call. */
public void startCall() throws IOException { os.write('c'); os.write(0); os.write(1); }
Writes the method tag.
m b16 b8 method-name
Params:
  • method – the method name to call.
/** * Writes the method tag. * * <code><pre> * m b16 b8 method-name * </pre></code> * * @param method the method name to call. */
public void writeMethod(String method) throws IOException { os.write('m'); int len = method.length(); os.write(len >> 8); os.write(len); printString(method, 0, len); }
Completes.
z
/** * Completes. * * <code><pre> * z * </pre></code> */
public void completeCall() throws IOException { os.write('z'); }
Starts the reply

A successful completion will have a single value:

r
/** * Starts the reply * * <p>A successful completion will have a single value: * * <pre> * r * </pre> */
public void startReply() throws IOException { os.write('r'); os.write(1); os.write(0); }
Completes reading the reply

A successful completion will have a single value:

z
/** * Completes reading the reply * * <p>A successful completion will have a single value: * * <pre> * z * </pre> */
public void completeReply() throws IOException { os.write('z'); }
Writes a header name. The header value must immediately follow.
H b16 b8 foo value
/** * Writes a header name. The header value must immediately follow. * * <code><pre> * H b16 b8 foo <em>value</em> * </pre></code> */
public void writeHeader(String name) throws IOException { int len = name.length(); os.write('H'); os.write(len >> 8); os.write(len); printString(name); }
Writes a fault. The fault will be written as a descriptive string followed by an object:
f
<string>code
<string>the fault code
<string>message
<string>the fault mesage
<string>detail
mt\x00\xnnjavax.ejb.FinderException
    ...
z
z
Params:
  • code – the fault code, a three digit
/** * Writes a fault. The fault will be written * as a descriptive string followed by an object: * * <code><pre> * f * &lt;string>code * &lt;string>the fault code * * &lt;string>message * &lt;string>the fault mesage * * &lt;string>detail * mt\x00\xnnjavax.ejb.FinderException * ... * z * z * </pre></code> * * @param code the fault code, a three digit */
public void writeFault(String code, String message, Object detail) throws IOException { // hessian/3525 os.write('r'); os.write(1); os.write(0); os.write('f'); writeString("code"); writeString(code); writeString("message"); writeString(message); if (detail != null) { writeString("detail"); writeObject(detail); } os.write('z'); os.write('z'); }
Writes any object to the output stream.
/** * Writes any object to the output stream. */
public void writeObject(Object object) throws IOException { if (object == null) { writeNull(); return; } Serializer serializer; serializer = _serializerFactory.getSerializer(object.getClass()); serializer.writeObject(object, this); }
Writes the list header to the stream. List writers will call writeListBegin followed by the list contents and then call writeListEnd.
V
t b16 b8 type
l b32 b24 b16 b8
/** * 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> * V * t b16 b8 type * l b32 b24 b16 b8 * </pre></code> */
public boolean writeListBegin(int length, String type) throws IOException { os.write('V'); if (type != null) { os.write('t'); printLenString(type); } if (length >= 0) { os.write('l'); os.write(length >> 24); os.write(length >> 16); os.write(length >> 8); os.write(length); } return true; }
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 ( )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 (<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); }
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 double value to the stream. The double will be written with the following syntax:
D b64 b56 b48 b40 b32 b24 b16 b8
Params:
  • value – the double value to write.
/** * Writes a double value to the stream. The double will be written * with the following syntax: * * <code><pre> * D b64 b56 b48 b40 b32 b24 b16 b8 * </pre></code> * * @param value the double value to write. */
public void writeDouble(double value) throws IOException { long bits = Double.doubleToLongBits(value); os.write('D'); os.write((byte) (bits >> 56)); os.write((byte) (bits >> 48)); os.write((byte) (bits >> 40)); os.write((byte) (bits >> 32)); os.write((byte) (bits >> 24)); os.write((byte) (bits >> 16)); os.write((byte) (bits >> 8)); os.write((byte) (bits)); }
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 length = value.length(); int offset = 0; while (length > 0x8000) { int sublen = 0x8000; // chunk can't end in high surrogate char tail = value.charAt(offset + sublen - 1); if (0xd800 <= tail && tail <= 0xdbff) sublen--; os.write('s'); os.write(sublen >> 8); os.write(sublen); printString(value, offset, sublen); length -= sublen; offset += sublen; } os.write('S'); os.write(length >> 8); os.write(length); printString(value, offset, length); } }
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(char []buffer, int offset, int length) throws IOException { if (buffer == null) { os.write('N'); } else { while (length > 0x8000) { int sublen = 0x8000; // chunk can't end in high surrogate char tail = buffer[offset + sublen - 1]; if (0xd800 <= tail && tail <= 0xdbff) sublen--; os.write('s'); os.write(sublen >> 8); os.write(sublen); printString(buffer, offset, sublen); length -= sublen; offset += sublen; } os.write('S'); os.write(length >> 8); os.write(length); printString(buffer, offset, 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) 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 { while (length > 0x8000) { int sublen = 0x8000; os.write('b'); os.write(sublen >> 8); os.write(sublen); os.write(buffer, offset, sublen); length -= sublen; offset += sublen; } os.write('B'); os.write(length >> 8); os.write(length); os.write(buffer, offset, length); } }
Writes a byte buffer to the stream.
/** * Writes a byte buffer to the stream. * * <code><pre> * </pre></code> */
public void writeByteBufferStart() throws IOException { }
Writes a byte buffer to the stream.
b b16 b18 bytes
/** * Writes a byte buffer to the stream. * * <code><pre> * b b16 b18 bytes * </pre></code> */
public void writeByteBufferPart(byte []buffer, int offset, int length) throws IOException { while (length > 0) { int sublen = length; if (0x8000 < sublen) sublen = 0x8000; os.write('b'); os.write(sublen >> 8); os.write(sublen); os.write(buffer, offset, sublen); length -= sublen; offset += sublen; } }
Writes a byte buffer to the stream.
b b16 b18 bytes
/** * Writes a byte buffer to the stream. * * <code><pre> * b b16 b18 bytes * </pre></code> */
public void writeByteBufferEnd(byte []buffer, int offset, int length) throws IOException { writeBytes(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 placeholder.
P
/** * Writes a placeholder. * * <code><pre> * P * </pre></code> */
public void writePlaceholder() throws IOException { os.write('P'); }
If the object has already been written, just write its ref.
Returns:true if we're writing a ref.
/** * If the object has already been written, just write its ref. * * @return true if we're writing a ref. */
public boolean addRef(Object object) throws IOException { if (_refs == null) _refs = new IdentityHashMap(); Integer ref = (Integer) _refs.get(object); if (ref != null) { int value = ref.intValue(); writeRef(value); return true; } else { _refs.put(object, new Integer(_refs.size())); return false; } } @Override public int getRef(Object obj) { Integer value; if (_refs == null) return -1; value = (Integer) _refs.get(obj); if (value == null) return -1; else return value; }
Resets the references for streaming.
/** * Resets the references for streaming. */
public void resetReferences() { if (_refs != null) _refs.clear(); }
Removes a reference.
/** * Removes a reference. */
public boolean removeRef(Object obj) throws IOException { if (_refs != null) { _refs.remove(obj); return true; } else return false; }
Replaces a reference from one object to another.
/** * Replaces a reference from one object to another. */
public boolean replaceRef(Object oldRef, Object newRef) throws IOException { Integer value = (Integer) _refs.remove(oldRef); if (value != null) { _refs.put(newRef, value); return true; } else return false; }
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)); } } }
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(char []v, int offset, int length) throws IOException { for (int i = 0; i < length; i++) { char ch = v[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)); } } } public void flush() throws IOException { if (this.os != null) this.os.flush(); } public void close() throws IOException { if (this.os != null) this.os.flush(); } }