javax.jms
Interface StreamMessage


public abstract interface StreamMessage
extends Message

A StreamMessage is used to send a stream of Java primitives. It is filled and read sequentially. It inherits from Message and adds a stream message body. It's methods are based largely on those found in java.io.DataInputStream and java.io.DataOutputStream.

The primitive types can be read or written explicitly using methods for each type. They may also be read or written generically as objects. For instance, a call to StreamMessage.writeInt(6) is equivalent to StreamMessage.writeObject(new Integer(6)). Both forms are provided because the explicit form is convenient for static programming and the object form is needed when types are not known at compile time.

When the message is first created, and when clearBody is called, the body of the message is in write-only mode. After the first call to reset has been made, the message is in read-only mode. When a message has been sent, by definition, the provider calls reset in order to read it's content, and when a message has been received, the provider has called reset so that the message is in read-only mode for the client.

If clearBody is called on a message in read-only mode, the message body is cleared and the message is in write-only mode.

If a client attempts to read a message in write-only mode, a MessageNotReadableException is thrown.

If a client attempts to write a message in read-only mode, a MessageNotWriteableException is thrown.

Stream messages support the following conversion table. The marked cases must be supported. The unmarked cases must throw a JMSException. The String to primitive conversions may throw a runtime exception if the primitives valueOf() method does not accept it as a valid String representation of the primitive.

A value written as the row type can be read as the column type.


 |        | boolean byte short char int long float double String byte[]

 |----------------------------------------------------------------------

 |boolean |    X                                            X

 |byte    |          X     X         X   X                  X   

 |short   |                X         X   X                  X   

 |char    |                     X                           X

 |int     |                          X   X                  X   

 |long    |                              X                  X   

 |float   |                                    X     X      X   

 |double  |                                          X      X   

 |String  |    X     X     X    X    X   X     X     X      X   

 |byte[]  |                                                        X

 |----------------------------------------------------------------------

 

Version:
1.0 - 6 August 1998
Author:
Mark Hapner, Rich Burridge
See Also:
BytesMessage, MapMessage, Message, ObjectMessage, TextMessage, java.io.DataInputStream, java.io.DataOutputStream

Fields inherited from class javax.jms.Message
DEFAULT_DELIVERY_MODE, DEFAULT_PRIORITY, DEFAULT_TIME_TO_LIVE
 
Method Summary
 boolean readBoolean()
          Read a boolean from the stream message.
 byte readByte()
          Read a byte value from the stream message.
 int readBytes(byte[] value)
          Read a byte array from the stream message.
 char readChar()
          Read a Unicode character value from the stream message.
 double readDouble()
          Read a double from the stream message.
 float readFloat()
          Read a float from the stream message.
 int readInt()
          Read a 32-bit integer from the stream message.
 long readLong()
          Read a 64-bit integer from the stream message.
 java.lang.Object readObject()
          Read a Java object from the stream message.
 short readShort()
          Read a 16-bit number from the stream message.
 java.lang.String readString()
          Read in a string from the stream message.
 void reset()
          Put the message in read-only mode, and reposition the stream to the beginning.
 void writeBoolean(boolean value)
          Write a boolean to the stream message.
 void writeByte(byte value)
          Write out a byte to the stream message.
 void writeBytes(byte[] value)
          Write a byte array to the stream message.
 void writeBytes(byte[] value, int offset, int length)
          Write a portion of a byte array to the stream message.
 void writeChar(char value)
          Write a char to the stream message.
 void writeDouble(double value)
          Write a double to the stream message.
 void writeFloat(float value)
          Write a float to the stream message.
 void writeInt(int value)
          Write an int to the stream message.
 void writeLong(long value)
          Write a long to the stream message.
 void writeObject(java.lang.Object value)
          Write a Java object to the stream message.
 void writeShort(short value)
          Write a short to the stream message.
 void writeString(java.lang.String value)
          Write a string to the stream message.
 
Methods inherited from interface javax.jms.Message
acknowledge, clearBody, clearProperties, getBooleanProperty, getByteProperty, getDoubleProperty, getFloatProperty, getIntProperty, getJMSCorrelationID, getJMSCorrelationIDAsBytes, getJMSDeliveryMode, getJMSDestination, getJMSExpiration, getJMSMessageID, getJMSPriority, getJMSRedelivered, getJMSReplyTo, getJMSTimestamp, getJMSType, getLongProperty, getObjectProperty, getPropertyNames, getShortProperty, getStringProperty, propertyExists, setBooleanProperty, setByteProperty, setDoubleProperty, setFloatProperty, setIntProperty, setJMSCorrelationID, setJMSCorrelationIDAsBytes, setJMSDeliveryMode, setJMSDestination, setJMSExpiration, setJMSMessageID, setJMSPriority, setJMSRedelivered, setJMSReplyTo, setJMSTimestamp, setJMSType, setLongProperty, setObjectProperty, setShortProperty, setStringProperty
 

Method Detail

readBoolean


public boolean readBoolean()

                    throws JMSException
Read a boolean from the stream message.
Returns:
the boolean value read.
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageEOFException - if an end of message stream * @exception MessageFormatException if this type conversion is invalid
MessageNotReadableException - if message in write-only mode.

readByte


public byte readByte()

              throws JMSException
Read a byte value from the stream message.
Returns:
the next byte from the stream message as a 8-bit byte.
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageEOFException - if an end of message stream * @exception MessageFormatException if this type conversion is invalid
MessageNotReadableException - if message in write-only mode.

readShort


public short readShort()

                throws JMSException
Read a 16-bit number from the stream message.
Returns:
a 16-bit number from the stream message.
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageEOFException - if an end of message stream * @exception MessageFormatException if this type conversion is invalid * @exception MessageNotReadableException if message in write-only mode.

readChar


public char readChar()

              throws JMSException
Read a Unicode character value from the stream message.
Returns:
a Unicode character from the stream message.
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageEOFException - if an end of message stream * @exception MessageFormatException if this type conversion is invalid * @exception MessageNotReadableException if message in write-only mode.

readInt


public int readInt()

            throws JMSException
Read a 32-bit integer from the stream message.
Returns:
a 32-bit integer value from the stream message, interpreted as a int.
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageEOFException - if an end of message stream * @exception MessageFormatException if this type conversion is invalid * @exception MessageNotReadableException if message in write-only mode.

readLong


public long readLong()

              throws JMSException
Read a 64-bit integer from the stream message.
Returns:
a 64-bit integer value from the stream message, interpreted as a long.
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageEOFException - if an end of message stream * @exception MessageFormatException if this type conversion is invalid * @exception MessageNotReadableException if message in write-only mode.

readFloat


public float readFloat()

                throws JMSException
Read a float from the stream message.
Returns:
a float value from the stream message.
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageEOFException - if an end of message stream * @exception MessageFormatException if this type conversion is invalid
MessageNotReadableException - if message in write-only mode.

readDouble


public double readDouble()

                  throws JMSException
Read a double from the stream message.
Returns:
a double value from the stream message.
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageEOFException - if an end of message stream * @exception MessageFormatException if this type conversion is invalid
MessageNotReadableException - if message in write-only mode.

readString


public java.lang.String readString()

                            throws JMSException
Read in a string from the stream message.
Returns:
a Unicode string from the stream message.
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageEOFException - if an end of message stream * @exception MessageFormatException if this type conversion is invalid
MessageNotReadableException - if message in write-only mode.

readBytes


public int readBytes(byte[] value)

              throws JMSException
Read a byte array from the stream message.
Parameters:
value - the buffer into which the data is read.
Returns:
the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageEOFException - if an end of message stream * @exception MessageFormatException if this type conversion is invalid
MessageNotReadableException - if message in write-only mode.

readObject


public java.lang.Object readObject()

                            throws JMSException
Read a Java object from the stream message.

Note that this method can be used to return in objectified format, an object that had been written to the Stream with the equivalent writeObject method call, or it's equivalent primitive write method.

Returns:
a Java object from the stream message, in objectified format (ie. if it set as an int, then a Integer is returned).
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageEOFException - if an end of message stream * @exception MessageNotReadableException if message in write-only mode.

writeBoolean


public void writeBoolean(boolean value)

                  throws JMSException
Write a boolean to the stream message. The value true is written out as the value (byte)1; the value false is written out as the value (byte)0.
Parameters:
value - the boolean value to be written.
Throws:
JMSException - if JMS fails to read message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.

writeByte


public void writeByte(byte value)

               throws JMSException
Write out a byte to the stream message.
Parameters:
value - the byte value to be written.
Throws:
JMSException - if JMS fails to write message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.

writeShort


public void writeShort(short value)

                throws JMSException
Write a short to the stream message.
Parameters:
value - the short to be written.
Throws:
JMSException - if JMS fails to write message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.

writeChar


public void writeChar(char value)

               throws JMSException
Write a char to the stream message.
Parameters:
value - the char value to be written.
Throws:
JMSException - if JMS fails to write message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.

writeInt


public void writeInt(int value)

              throws JMSException
Write an int to the stream message.
Parameters:
value - the int to be written.
Throws:
JMSException - if JMS fails to write message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.

writeLong


public void writeLong(long value)

               throws JMSException
Write a long to the stream message.
Parameters:
value - the long to be written.
Throws:
JMSException - if JMS fails to write message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.

writeFloat


public void writeFloat(float value)

                throws JMSException
Write a float to the stream message.
Parameters:
value - the float value to be written.
Throws:
JMSException - if JMS fails to write message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.

writeDouble


public void writeDouble(double value)

                 throws JMSException
Write a double to the stream message.
Parameters:
value - the double value to be written.
Throws:
JMSException - if JMS fails to write message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.

writeString


public void writeString(java.lang.String value)

                 throws JMSException
Write a string to the stream message.
Parameters:
value - the String value to be written.
Throws:
JMSException - if JMS fails to write message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.

writeBytes


public void writeBytes(byte[] value)

                throws JMSException
Write a byte array to the stream message.
Parameters:
value - the byte array to be written.
Throws:
JMSException - if JMS fails to write message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.

writeBytes


public void writeBytes(byte[] value,

                       int offset,

                       int length)

                throws JMSException
Write a portion of a byte array to the stream message.
Parameters:
value - the byte array value to be written.
offset - the initial offset within the byte array.
length - the number of bytes to use.
Throws:
JMSException - if JMS fails to write message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.

writeObject


public void writeObject(java.lang.Object value)

                 throws JMSException
Write a Java object to the stream message.

Note that this method only works for the objectified primitive object types (Integer, Double, Long ...), String's and byte arrays.

Parameters:
value - the Java object to be written.
Throws:
JMSException - if JMS fails to write message due to some internal JMS error.
MessageNotWriteableException - if message in read-only mode.
MessageFormatException - if the object is invalid

reset


public void reset()

           throws JMSException
Put the message in read-only mode, and reposition the stream to the beginning.
Throws:
JMSException - if JMS fails to reset the message due to some internal JMS error.
MessageFormatException - if message has an invalid format