com.j_spaces.jms
Class GSStreamMessageImpl

java.lang.Object
  extended by com.j_spaces.core.client.MetaDataEntry
      extended by com.j_spaces.jms.GSMessageImpl
          extended by com.j_spaces.jms.GSStreamMessageImpl
All Implemented Interfaces:
IMetaDataEntry, Externalizable, Serializable, Message, StreamMessage, Entry

public class GSStreamMessageImpl
extends GSMessageImpl
implements StreamMessage

Implements the javax.jms.StreamMessage interface for the GigaSpaces JMS API. A StreamMessage object is used to send a stream of primitive types in the Java programming language. It is filled and read sequentially. It inherits from the Message interface and adds a stream message body. Its 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 body is in read-only mode. After a message has been sent, the client that sent it can retain and modify it without affecting the message that has been sent. The same message object can be sent multiple times. When a message has been received, the provider has called reset so that the message body 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 body 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.

StreamMessage objects 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 primitive's 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
 |byte[]  |                                                        X
 |----------------------------------------------------------------------
 

Attempting to read a null value as a primitive type must be treated as calling the primitive's corresponding valueOf(String) conversion method with a null value. Since char does not support a String conversion, attempting to read a null value as a char must throw a NullPointerException.

See Also:
Session.createStreamMessage(), BytesMessage, MapMessage, Message, ObjectMessage, TextMessage, Serialized Form

Field Summary
 
Fields inherited from class com.j_spaces.jms.GSMessageImpl
Body, BODY_STR_NAME, BYTES, DestinationName, JMS_CORRELATION_ID, JMS_DELIVERY_MODE, JMS_DESTINATION, JMS_EXPIRATION, JMS_GSCONNECTION_KEY_NAME, JMS_GSCONVERTER, JMS_GSPRODUCER_KEY_PROP_NAME, JMS_GSTTL_KEY_PROP_NAME, JMS_MESSAGE_ID, JMS_PRIORITY, JMS_REDELIVERED, JMS_REPLY_TO, JMS_TIMESTAMP, JMS_TYPE, JMSCorrelationID, JMSDeliveryMode, JMSDestination, JMSExpiration, JMSMessageID, JMSPriority, JMSRedelivered, JMSReplyTo, JMSTimestamp, JMSType, JMSX_GROUPID, JMSX_GROUPSEQ, JMSX_USERID, MAP, OBJECT, Properties, PROPERTIES_STR_NAME, SIMPLE, STREAM, TEXT
 
Fields inherited from interface javax.jms.Message
DEFAULT_DELIVERY_MODE, DEFAULT_PRIORITY, DEFAULT_TIME_TO_LIVE
 
Constructor Summary
GSStreamMessageImpl()
           
 
Method Summary
 void clearBody()
          Override the super class method to reset the streams, and put the message body in write only mode.
 com.j_spaces.jms.utils.ByteArray getBodyAsBytes()
           
 boolean readBoolean()
          Reads a boolean from the stream message.
 byte readByte()
          Reads a byte value from the stream message.
 int readBytes(byte[] value)
          Reads a byte array field from the stream message into the specified byte[] object (the read buffer).
 char readChar()
          Reads a Unicode character value from the stream message.
 double readDouble()
          Reads a double from the stream message.
 float readFloat()
          Reads a float from the stream message.
 int readInt()
          Reads a 32-bit integer from the stream message.
 long readLong()
          Reads a 64-bit integer from the stream message.
 Object readObject()
          Reads an object from the stream message.
 short readShort()
          Reads a 16-bit integer from the stream message.
 String readString()
          Reads a String from the stream message.
 void reset()
          Puts the message body in read-only mode and repositions the stream of bytes to the beginning.
 void setBodyAsBytes(byte[] bodyAsBytes, int offset, int length)
           
 String toString()
           
 void writeBoolean(boolean value)
          Writes a boolean to the stream message.
 void writeByte(byte value)
          Writes a byte to the stream message.
 void writeBytes(byte[] value)
          Writes a byte array field to the stream message.
 void writeBytes(byte[] value, int offset, int length)
          Writes a portion of a byte array as a byte array field to the stream message.
 void writeChar(char value)
          Writes a char to the stream message.
 void writeDouble(double value)
          Writes a double to the stream message.
 void writeFloat(float value)
          Writes a float to the stream message.
 void writeInt(int value)
          Writes an int to the stream message.
 void writeLong(long value)
          Writes a long to the stream message.
 void writeObject(Object value)
          Writes an object to the stream message.
 void writeShort(short value)
          Writes a short to the stream message.
 void writeString(String value)
          Writes a String to the stream message.
 
Methods inherited from class com.j_spaces.jms.GSMessageImpl
__getSpaceIndexedFields, acknowledge, clearProperties, equals, getBooleanProperty, getByteProperty, getDestinationName, getDoubleProperty, getFloatProperty, getIntProperty, getJMSCorrelationID, getJMSCorrelationIDAsBytes, getJMSDeliveryMode, getJMSDestination, getJMSExpiration, getJMSMessageID, getJMSPriority, getJMSRedelivered, getJMSReplyTo, getJMSTimestamp, getJMSType, getLongProperty, getObjectProperty, getPropertyNames, getShortProperty, getStringProperty, hashcode, propertyExists, readExternal, setBooleanProperty, setByteProperty, setDestinationName, setDoubleProperty, setFloatProperty, setIntProperty, setJMSCorrelationID, setJMSCorrelationIDAsBytes, setJMSDeliveryMode, setJMSDestination, setJMSExpiration, setJMSMessageID, setJMSPriority, setJMSRedelivered, setJMSReplyTo, setJMSTimestamp, setJMSType, setLongProperty, setObjectProperty, setProperties, setRoutingIndexes, setShortProperty, setStringProperty, writeExternal
 
Methods inherited from class com.j_spaces.core.client.MetaDataEntry
__getEntryInfo, __setEntryInfo, isFifo, isNOWriteLeaseMode, isTransient, makePersistent, makeTransient, setFifo, setNOWriteLeaseMode
 
Methods inherited from class java.lang.Object
getClass, hashCode, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface javax.jms.Message
acknowledge, 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

GSStreamMessageImpl

public GSStreamMessageImpl()
                    throws JMSException
Throws:
JMSException
Method Detail

readBoolean

public boolean readBoolean()
                    throws JMSException
Reads a boolean from the stream message.

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

readByte

public byte readByte()
              throws JMSException
Reads a byte value from the stream message.

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

readShort

public short readShort()
                throws JMSException
Reads a 16-bit integer from the stream message.

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

readChar

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

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

readInt

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

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

readLong

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

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

readFloat

public float readFloat()
                throws JMSException
Reads a float from the stream message.

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

readDouble

public double readDouble()
                  throws JMSException
Reads a double from the stream message.

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

readString

public String readString()
                  throws JMSException
Reads a String from the stream message.

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

readBytes

public int readBytes(byte[] value)
              throws JMSException
Reads a byte array field from the stream message into the specified byte[] object (the read buffer).

To read the field value, readBytes should be successively called until it returns a value less than the length of the read buffer. The value of the bytes in the buffer following the last byte read is undefined.

If readBytes returns a value equal to the length of the buffer, a subsequent readBytes call must be made. If there are no more bytes to be read, this call returns -1.

If the byte array field value is null, readBytes returns -1.

If the byte array field value is empty, readBytes returns 0.

Once the first readBytes call on a byte[] field value has been made, the full value of the field must be read before it is valid to read the next field. An attempt to read the next field before that has been done will throw a MessageFormatException.

To read the byte field value into a new byte[] object, use the readObject method.

Specified by:
readBytes in interface 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 byte field has been reached
Throws:
JMSException - if the JMS provider fails to read the message due to some internal error.
MessageEOFException - if unexpected end of message stream has been reached.
MessageFormatException - if this type conversion is invalid.
MessageNotReadableException - if the message is in write-only mode.
See Also:
readObject()

readObject

public Object readObject()
                  throws JMSException
Reads an object from the stream message.

This method can be used to return, in objectified format, an object in the Java programming language ("Java object") that has been written to the stream with the equivalent writeObject method call, or its equivalent primitive writetype method.

Note that byte values are returned as byte[], not Byte[].

An attempt to call readObject to read a byte field value into a new byte[] object before the full value of the byte field has been read will throw a MessageFormatException.

Specified by:
readObject in interface StreamMessage
Returns:
a Java object from the stream message, in objectified format (for example, if the object was written as an int, an Integer is returned)
Throws:
JMSException - if the JMS provider fails to read the message due to some internal error.
MessageEOFException - if unexpected end of message stream has been reached.
MessageFormatException - if this type conversion is invalid.
MessageNotReadableException - if the message is in write-only mode.
See Also:
readBytes(byte[] value)

writeBoolean

public void writeBoolean(boolean value)
                  throws JMSException
Writes a boolean to the stream message. The value true is written as the value (byte)1; the value false is written as the value (byte)0.

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

writeByte

public void writeByte(byte value)
               throws JMSException
Writes a byte to the stream message.

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

writeShort

public void writeShort(short value)
                throws JMSException
Writes a short to the stream message.

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

writeChar

public void writeChar(char value)
               throws JMSException
Writes a char to the stream message.

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

writeInt

public void writeInt(int value)
              throws JMSException
Writes an int to the stream message.

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

writeLong

public void writeLong(long value)
               throws JMSException
Writes a long to the stream message.

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

writeFloat

public void writeFloat(float value)
                throws JMSException
Writes a float to the stream message.

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

writeDouble

public void writeDouble(double value)
                 throws JMSException
Writes a double to the stream message.

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

writeString

public void writeString(String value)
                 throws JMSException
Writes a String to the stream message.

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

writeBytes

public void writeBytes(byte[] value)
                throws JMSException
Writes a byte array field to the stream message.

The byte array value is written to the message as a byte array field. Consecutively written byte array fields are treated as two distinct fields when the fields are read.

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

writeBytes

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

The a portion of the byte array value is written to the message as a byte array field. Consecutively written byte array fields are treated as two distinct fields when the fields are read.

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

writeObject

public void writeObject(Object value)
                 throws JMSException
Writes an object to the stream message.

This method works only for the objectified primitive object types (Integer, Double, Long ...), String objects, and byte arrays.

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

setBodyAsBytes

public void setBodyAsBytes(byte[] bodyAsBytes,
                           int offset,
                           int length)
Parameters:
bodyAsBytes - The bodyAsBytes to set.
offset -
length -

getBodyAsBytes

public com.j_spaces.jms.utils.ByteArray getBodyAsBytes()
                                                throws IOException
Returns:
Returns the data body
Throws:
IOException - if an exception occurs retreiving the data

reset

public void reset()
           throws JMSException
Puts the message body in read-only mode and repositions the stream of bytes to the beginning.

Specified by:
reset in interface StreamMessage
Throws:
JMSException - if an internal error occurs

clearBody

public void clearBody()
               throws JMSException
Override the super class method to reset the streams, and put the message body in write only mode.

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

If clearBody is called on a message already in write-only mode, the spec does not define the outcome, so do nothing. Client must then call reset, followed by clearBody to reset the stream at the beginning for a new write.

Specified by:
clearBody in interface Message
Overrides:
clearBody in class GSMessageImpl
Throws:
JMSException - if JMS fails to reset the message due to some internal JMS error
See Also:
Message.clearBody()

toString

public String toString()
Overrides:
toString in class GSMessageImpl
See Also:
Object.toString()