Websphere MQ Everyplace

com.ibm.mqe.jms
Class MQeStreamMessage

java.lang.Object
  |
  +--com.ibm.mqe.jms.MQeMessage
        |
        +--com.ibm.mqe.jms.MQeStreamMessage
All Implemented Interfaces:
javax.jms.Message, javax.jms.StreamMessage

public class MQeStreamMessage
extends MQeMessage
implements javax.jms.StreamMessage

A StreamMessage is used to send a stream of Java primitives. It is filled and read sequentially. It inherits from MQeMessage and adds a stream message body.

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 MQeMessage.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 MQeMessage.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
 |----------------------------------------------------------------------
 

See Also:
BytesMessage, MapMessage, Message, ObjectMessage, TextMessage

Field Summary
 
Fields inherited from class com.ibm.mqe.jms.MQeMessage
DEFAULT_DELIVERY_MODE
 
Fields inherited from interface javax.jms.Message
DEFAULT_DELIVERY_MODE, DEFAULT_PRIORITY, DEFAULT_TIME_TO_LIVE
 
Constructor Summary
MQeStreamMessage()
           
 
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 class com.ibm.mqe.jms.MQeMessage
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
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
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
 

Constructor Detail

MQeStreamMessage

public MQeStreamMessage()
Method Detail

readBoolean

public boolean readBoolean()
                    throws javax.jms.JMSException
Read a boolean from the stream message.

Specified by:
readBoolean in interface javax.jms.StreamMessage
Returns:
the boolean value read.
Throws:
javax.jms.JMSException - if JMS fails to read from the message due to some internal JMS error.
javax.jms.MessageEOFException - if the end of the message stream is reached
javax.jms.MessageFormatException - if this type conversion is invalid
javax.jms.MessageNotReadableException - if message in write-only mode.

readByte

public byte readByte()
              throws javax.jms.JMSException
Read a byte value from the stream message.

Specified by:
readByte in interface javax.jms.StreamMessage
Returns:
the next byte from the stream message as a 8-bit byte.
Throws:
javax.jms.JMSException - if JMS fails to read from the message due to some internal JMS error.
javax.jms.MessageEOFException - if the end of the message stream is reached
javax.jms.MessageFormatException - if this type conversion is invalid
javax.jms.MessageNotReadableException - if message in write-only mode.

readShort

public short readShort()
                throws javax.jms.JMSException
Read a 16-bit number from the stream message.

Specified by:
readShort in interface javax.jms.StreamMessage
Returns:
a 16-bit number from the stream message.
Throws:
javax.jms.JMSException - if JMS fails to read from the message due to some internal JMS error.
javax.jms.MessageEOFException - if the end of the message stream is reached
javax.jms.MessageFormatException - if this type conversion is invalid
javax.jms.MessageNotReadableException - if message in write-only mode.

readChar

public char readChar()
              throws javax.jms.JMSException
Read a Unicode character value from the stream message.

Specified by:
readChar in interface javax.jms.StreamMessage
Returns:
a Unicode character from the stream message.
Throws:
javax.jms.JMSException - if JMS fails to read from the message due to some internal JMS error.
javax.jms.MessageEOFException - if the end of the message stream is reached
javax.jms.MessageFormatException - if this type conversion is invalid
javax.jms.MessageNotReadableException - if message in write-only mode.

readInt

public int readInt()
            throws javax.jms.JMSException
Read a 32-bit integer from the stream message.

Specified by:
readInt in interface javax.jms.StreamMessage
Returns:
a 32-bit integer value from the stream message, interpreted as a int.
Throws:
javax.jms.JMSException - if JMS fails to read from the message due to some internal JMS error.
javax.jms.MessageEOFException - if the end of the message stream is reached
javax.jms.MessageFormatException - if this type conversion is invalid
javax.jms.MessageNotReadableException - if message in write-only mode.

readLong

public long readLong()
              throws javax.jms.JMSException
Read a 64-bit integer from the stream message.

Specified by:
readLong in interface javax.jms.StreamMessage
Returns:
a 64-bit integer value from the stream message, interpreted as a long.
Throws:
javax.jms.JMSException - if JMS fails to read from the message due to some internal JMS error.
javax.jms.MessageEOFException - if the end of the message stream is reached
javax.jms.MessageFormatException - if this type conversion is invalid
javax.jms.MessageNotReadableException - if message in write-only mode.

readFloat

public float readFloat()
                throws javax.jms.JMSException
Read a float from the stream message.

Specified by:
readFloat in interface javax.jms.StreamMessage
Returns:
a float value from the stream message.
Throws:
javax.jms.JMSException - if JMS fails to read from the message due to some internal JMS error.
javax.jms.MessageEOFException - if the end of the message stream is reached
javax.jms.MessageFormatException - if this type conversion is invalid
javax.jms.MessageNotReadableException - if message in write-only mode.

readDouble

public double readDouble()
                  throws javax.jms.JMSException
Read a double from the stream message.

Specified by:
readDouble in interface javax.jms.StreamMessage
Returns:
a double value from the stream message.
Throws:
javax.jms.JMSException - if JMS fails to read from the message due to some internal JMS error.
javax.jms.MessageEOFException - if the end of the message stream is reached
javax.jms.MessageFormatException - if this type conversion is invalid
javax.jms.MessageNotReadableException - if message in write-only mode.

readString

public java.lang.String readString()
                            throws javax.jms.JMSException
Read in a string from the stream message.

Specified by:
readString in interface javax.jms.StreamMessage
Returns:
a Unicode string from the stream message.
Throws:
javax.jms.JMSException - if JMS fails to read from the message due to some internal JMS error.
javax.jms.MessageEOFException - if the end of the message stream is reached
javax.jms.MessageFormatException - if this type conversion is invalid
javax.jms.MessageNotReadableException - if message in write-only mode.

readBytes

public int readBytes(byte[] value)
              throws javax.jms.JMSException
Read a byte array from the stream message.

Specified by:
readBytes in interface javax.jms.StreamMessage
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:
javax.jms.JMSException - if JMS fails to read from the message due to some internal JMS error.
javax.jms.MessageEOFException - if the end of the message stream is reached
javax.jms.MessageFormatException - if this type conversion is invalid
javax.jms.MessageNotReadableException - if message in write-only mode.

readObject

public java.lang.Object readObject()
                            throws javax.jms.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.

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

writeBoolean

public void writeBoolean(boolean value)
                  throws javax.jms.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.

Specified by:
writeBoolean in interface javax.jms.StreamMessage
Parameters:
value - the boolean value to be written.
Throws:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageNotWriteableException - if message in read-only mode.

writeByte

public void writeByte(byte value)
               throws javax.jms.JMSException
Write out a byte to the stream message.

Specified by:
writeByte in interface javax.jms.StreamMessage
Parameters:
value - the byte value to be written.
Throws:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageNotWriteableException - if message in read-only mode.

writeShort

public void writeShort(short value)
                throws javax.jms.JMSException
Write a short to the stream message.

Specified by:
writeShort in interface javax.jms.StreamMessage
Parameters:
value - the short to be written.
Throws:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageNotWriteableException - if message in read-only mode.

writeChar

public void writeChar(char value)
               throws javax.jms.JMSException
Write a char to the stream message.

Specified by:
writeChar in interface javax.jms.StreamMessage
Parameters:
value - the char value to be written.
Throws:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageNotWriteableException - if message in read-only mode.

writeInt

public void writeInt(int value)
              throws javax.jms.JMSException
Write an int to the stream message.

Specified by:
writeInt in interface javax.jms.StreamMessage
Parameters:
value - the int to be written.
Throws:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageNotWriteableException - if message in read-only mode.

writeLong

public void writeLong(long value)
               throws javax.jms.JMSException
Write a long to the stream message.

Specified by:
writeLong in interface javax.jms.StreamMessage
Parameters:
value - the long to be written.
Throws:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageNotWriteableException - if message in read-only mode.

writeFloat

public void writeFloat(float value)
                throws javax.jms.JMSException
Write a float to the stream message.

Specified by:
writeFloat in interface javax.jms.StreamMessage
Parameters:
value - the float value to be written.
Throws:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageNotWriteableException - if message in read-only mode.

writeDouble

public void writeDouble(double value)
                 throws javax.jms.JMSException
Write a double to the stream message.

Specified by:
writeDouble in interface javax.jms.StreamMessage
Parameters:
value - the double value to be written.
Throws:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageNotWriteableException - if message in read-only mode.

writeString

public void writeString(java.lang.String value)
                 throws javax.jms.JMSException
Write a string to the stream message.

Specified by:
writeString in interface javax.jms.StreamMessage
Parameters:
value - the String value to be written.
Throws:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageNotWriteableException - if message in read-only mode.

writeBytes

public void writeBytes(byte[] value)
                throws javax.jms.JMSException
Write a byte array to the stream message.

Specified by:
writeBytes in interface javax.jms.StreamMessage
Parameters:
value - the byte array to be written.
Throws:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageNotWriteableException - if message in read-only mode.

writeBytes

public void writeBytes(byte[] value,
                       int offset,
                       int length)
                throws javax.jms.JMSException
Write a portion of a byte array to the stream message.

Specified by:
writeBytes in interface javax.jms.StreamMessage
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:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageNotWriteableException - if message in read-only mode.

writeObject

public void writeObject(java.lang.Object value)
                 throws javax.jms.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.

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

reset

public void reset()
           throws javax.jms.JMSException
Put the message in read-only mode, and reposition the stream to the beginning.

Specified by:
reset in interface javax.jms.StreamMessage
Throws:
javax.jms.JMSException - if the write fails due to some internal JMS error.
javax.jms.MessageFormatException - if message has an invalid format

Websphere MQ Everyplace