message.java

一个类似于openJMS分布在ObjectWeb之下的JMS消息中间件。

/*
 * JORAM: Java(TM) Open Reliable Asynchronous Messaging
 * Copyright (C) 2001 - ScalAgent Distributed Technologies
 * Copyright (C) 1996 - Dyade
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or any later version.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 * USA.
 *
 * Initial developer(s): Frederic Maistre (INRIA)
 * Contributor(s): Nicolas Tachker (ScalAgent)
 */
package com.scalagent.kjoram.messages;

import com.scalagent.kjoram.excepts.*;

import java.io.*;
import java.util.*;

/** 
 * The <code>Message</code> class actually provides the transport facility
 * for the data exchanged during MOM operations.
 * <p>
 * A message may either carry a String, or a serializable object, or an
 * hashtable, or bytes, even nothing. It is charaterized by properties and
 * "header" fields.
 */
public class Message {
  /** The message type (SIMPLE, TEXT, MAP, BYTES). */
  int type;

  /** <code>true</code> if the message must be persisted. **/
  boolean persistent = true;

  /** The message identifier. */
  String id = null;
  /** The message priority (from 0 to 9, 9 being the highest). */
  int priority = 4;
  /** The message expiration time (0 for infinite time-to-live). */
  long expiration = 0;
  /** The message time stamp. */
  long timestamp;
  /** The message destination identifier. */
  String toId = null;
  /** <code>true</code> if the message destination is a queue. */
  boolean toQueue;
  /** The correlation identifier field. */
  String correlationId = null;
  /** The reply to destination identifier. */
  String replyToId = null;
  /** <code>true</code> if the "reply to" destination is a queue. */
  boolean replyToQueue;

  /**
   * Table holding header fields that may be required by particular
   * clients (such as JMS clients).
   */
  Hashtable optionalHeader = null;

  /** The bytes body. */
  byte[] body_bytes = null;
  /** The map body. */
  Hashtable body_map = null;
  /** The text body. */
  String body_text = null;
  /** <code>true</code> if the body is read-only. */
  boolean bodyRO = false;

  /** The message properties table. */
  Hashtable properties = null;
  /** <code>true</code> if the properties are read-only. */
  boolean propertiesRO = false;

  /** The number of delivery attempts for this message. */
  public int deliveryCount = 0;
  /**
   * <code>true</code> if the message has been denied at least once by a
   * consumer.
   */
  public boolean denied = false;

  /** <code>true</code> if the message target destination is deleted. */
  public boolean deletedDest = false;
  /** <code>true</code> if the message expired. */
  public boolean expired = false;
  /** <code>true</code> if the message could not be written on the dest. */
  public boolean notWriteable = false;
  /** <code>true</code> if the message is considered as undeliverable. */
  public boolean undeliverable = false;
  
  /**
   * The number of acknowledgements a message still expects from its 
   * subscribers before having been fully consumed by them (field used
   * by JMS proxies).
   */
  public transient int acksCounter;
  /**
   * The number of acknowledgements a message still expects from its 
   * durable subscribers before having been fully consumed by them (field used
   * by JMS proxies).
   */
  public transient int durableAcksCounter;

  /**
   * Constructs a <code>Message</code> instance.
   */
  public Message()
  {
    this.type = MessageType.SIMPLE;
  }

  
  /** Sets the message identifier. */ 
  public void setIdentifier(String id)
  {
    this.id = id;
  }

  /** Sets the message persistence mode. */
  public void setPersistent(boolean persistent)
  {
    this.persistent = persistent;
  }

  /**
   * Sets the message priority.
   *
   * @param priority  Priority value: 0 the lowest, 9 the highest, 4 normal.
   */ 
  public void setPriority(int priority)
  {
    if (priority >= 0 && priority <= 9)
      this.priority = priority;
  }

  /** Sets the message expiration. */
  public void setExpiration(long expiration)
  {
    if (expiration >= 0)
      this.expiration = expiration;
  }

  /** Sets the message time stamp. */
  public void setTimestamp(long timestamp)
  {
    this.timestamp = timestamp;
  }

  /**
   * Sets the message destination.
   *
   * @param id  The destination identifier.
   * @param queue  <code>true</code> if the destination is a queue.
   */
  public void setDestination(String id, boolean queue)
  {
    this.toId = id;
    this.toQueue = queue;
  }

  /** Sets the message correlation identifier. */
  public void setCorrelationId(String correlationId)
  {
    this.correlationId = correlationId;
  }

  /**
   * Sets the destination to which a reply should be sent.
   *
   * @param id  The destination identifier.
   * @param queue  <code>true</code> if the destination is a queue.
   */
  public void setReplyTo(String id, boolean queue)
  {
    this.replyToId = id;
    this.replyToQueue = queue;
  }

  /**
   * Sets an optional header field value.
   *
   * @param name  The header field name.
   * @param value  The corresponding value.
   */
  public void setOptionalHeader(String name, Object value)
  {
    if (name == null || name.equals(""))
      throw new IllegalArgumentException("Invalid header name: " + name);

    if (value == null)
      return;

    if (optionalHeader == null)
      optionalHeader = new Hashtable();

    optionalHeader.put(name, value);
  }

  /** Returns the message type. */
  public int getType()
  {
    return type;
  }

  /** Returns the message identifier. */
  public String getIdentifier()
  {
    return id;
  }

  /** Returns <code>true</code> if the message is persistent. */
  public boolean getPersistent()
  {
    return persistent;
  }

  /** Returns the message priority. */
  public int getPriority()
  {
    return priority;
  }

  /** Returns the message expiration time. */
  public long getExpiration()
  {
    return expiration;
  }
  
  /** Returns the message time stamp. */
  public long getTimestamp()
  {
    return timestamp;
  }

  /** Returns the message destination identifier. */
  public String getDestinationId()
  {
    return toId;
  }

  /** Returns <code>true</code> if the destination is a queue. */
  public boolean toQueue()
  {
    return toQueue;
  }

  /** Returns the message correlation identifier. */
  public String getCorrelationId()
  {
    return correlationId;
  }

  /** Returns the destination id the reply should be sent to. */
  public String getReplyToId()
  {
    return replyToId;
  }

  /** Returns <code>true</code> if the reply to destination is a queue. */
  public boolean replyToQueue()
  {
    return replyToQueue;
  }

  /**
   * Returns an optional header field value.
   *
   * @param name  The header field name.
   */
  public Object getOptionalHeader(String name)
  {
    if (optionalHeader == null)
      return null;

    return optionalHeader.get(name);
  }

  /**
   * Sets a property as a boolean value.
   *
   * @param name  The property name.
   * @param value  The property value.
   *
   * @exception MessageROException  If the message properties are read-only.
   */
  public void setBooleanProperty(String name, boolean value)
         throws MessageROException
  {
    preparePropSetting(name);
    properties.put(name, new Boolean(value));
  }

  /**
   * Sets a property as a byte value.
   *
   * @param name  The property name.
   * @param value  The property value.
   *
   * @exception MessageROException  If the message properties are read-only.
   */
  public void setByteProperty(String name, byte value)
         throws MessageROException
  {
    preparePropSetting(name);
    properties.put(name, new Byte(value));
  }

  /**
   * Sets a property as a double value.
   *
   * @param name  The property name.
   * @param value  The property value.
   *
   * @exception MessageROException  If the message properties are read-only.
   */
//    public void setDoubleProperty(String name, double value)
//           throws MessageROException
//    {
//      preparePropSetting(name);
//      properties.put(name, new Double(value));
//    }

  /**
   * Sets a property as a float value.
   *
   * @param name  The property name.
   * @param value  The property value.
   *
   * @exception MessageROException  If the message properties are read-only.
   */
//    public void setFloatProperty(String name, float value)
//           throws MessageROException
//    {
//      preparePropSetting(name);
//      properties.put(name, new Float(value));
//    }

  /**
   * Sets a property as an int value.
   *
   * @param name  The property name.
   * @param value  The property value.
   *
   * @exception MessageROException  If the message properties are read-only.
   */
  public void setIntProperty(String name, int value) throws MessageROException
  {
    preparePropSetting(name);
    properties.put(name, new Integer(value));
  }

  /**
   * Sets a property as a long value.
   *
   * @param name  The property name.
   * @param value  The property value.
   *
   * @exception MessageROException  If the message properties are read-only.
   */
  public void setLongProperty(String name, long value)
         throws MessageROException
  {
    preparePropSetting(name);
    properties.put(name, new Long(value));
  }

  /**
   * Sets a property value.
   *
   * @param name  The property name.
   * @param value  The property value.
   *
   * @exception MessageROException  If the message properties are read-only.
   * @exception MessageValueException  If the value is not a Java primitive
   *              object.
   */
  public void setObjectProperty(String name, Object value)
         throws MessageException
  {
    preparePropSetting(name);

    if (value instanceof Boolean
        || value instanceof String
        || value instanceof Integer
        || value instanceof Long
        || value instanceof Short
        || value instanceof Byte)
      properties.put(name, value);

    else
      throw new MessageValueException("Can't set non primitive Java object"
                                      + " as a property value.");
  }

  /**
   * Sets a property as a short value.
   *
   * @param name  The property name.
   * @param value  The property value.
   *
   * @exception MessageROException  If the message properties are read-only.
   */
  public void setShortProperty(String name, short value)
         throws MessageROException
  {
    preparePropSetting(name);
    properties.put(name, new Short(value));
  }

  /**
   * Sets a property as a String.
   *
   * @param name  The property name.
   * @param value  The property value.
   *
   * @exception MessageROException  If the message properties are read-only.
   */
  public void setStringProperty(String name, String value)
         throws MessageROException
  {
    preparePropSetting(name);
    properties.put(name, new String(value));
  }

  /**
   * Returns a property as a boolean value.
   *
   * @exception MessageValueException  If the property type is invalid.
   */
  public boolean getBooleanProperty(String name) throws MessageValueException 
  {
    if (properties == null)
      throw new RuntimeException("getBooleanProperty properties = null");
    return ConversionHelper.toBoolean(properties.get(name));
  }
  
  /**
   *
   * @exception MessageValueException  If the property type is invalid.
   */