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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.
Session.createStreamMessage(), 
BytesMessage, 
MapMessage, 
Message, 
ObjectMessage, 
TextMessage| Field Summary | 
| Fields inherited from interface javax.jms.Message | 
| DEFAULT_DELIVERY_MODE, DEFAULT_PRIORITY, DEFAULT_TIME_TO_LIVE | 
| Method Summary | |
|  boolean | readBoolean()Reads a booleanfrom the stream message. | 
|  byte | readByte()Reads a bytevalue 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 doublefrom the stream message. | 
|  float | readFloat()Reads a floatfrom 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. | 
|  java.lang.Object | readObject()Reads an object from the stream message. | 
|  short | readShort()Reads a 16-bit integer from the stream message. | 
|  java.lang.String | readString()Reads a Stringfrom the stream message. | 
|  void | reset()Puts the message body in read-only mode and repositions the stream to the beginning. | 
|  void | writeBoolean(boolean value)Writes a booleanto the stream message. | 
|  void | writeByte(byte value)Writes a byteto 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 charto the stream message. | 
|  void | writeDouble(double value)Writes a doubleto the stream message. | 
|  void | writeFloat(float value)Writes a floatto the stream message. | 
|  void | writeInt(int value)Writes an intto the stream message. | 
|  void | writeLong(long value)Writes a longto the stream message. | 
|  void | writeObject(java.lang.Object value)Writes an object to the stream message. | 
|  void | writeShort(short value)Writes a shortto the stream message. | 
|  void | writeString(java.lang.String value)Writes a Stringto the stream message. | 
| Method Detail | 
public boolean readBoolean()
                    throws JMSException
boolean from the stream message.
boolean value read
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.
public byte readByte()
              throws JMSException
byte value from the stream message.
byte
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.
public short readShort()
                throws JMSException
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.
public char readChar()
              throws JMSException
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.
public int readInt()
            throws JMSException
int
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.
public long readLong()
              throws JMSException
long
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.
public float readFloat()
                throws JMSException
float from the stream message.
float value from the stream message
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.
public double readDouble()
                  throws JMSException
double from the stream message.
double value from the stream message
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.
public java.lang.String readString()
                            throws JMSException
String from the stream message.
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.
public int readBytes(byte[] value)
              throws JMSException
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.
value - the buffer into which the data is read
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.readObject()
public java.lang.Object readObject()
                            throws JMSException
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.
int, 
 an Integer is returned)
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(byte[] value)
public void writeBoolean(boolean value)
                  throws JMSException
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.
value - the boolean value to be written
JMSException - if the JMS provider fails to write the message
                         due to some internal error.
MessageNotWriteableException - if the message is in read-only 
                                         mode.
public void writeByte(byte value)
               throws JMSException
byte to the stream message.
value - the byte value to be written
JMSException - if the JMS provider fails to write the message
                         due to some internal error.
MessageNotWriteableException - if the message is in read-only 
                                         mode.
public void writeShort(short value)
                throws JMSException
short to the stream message.
value - the short value to be written
JMSException - if the JMS provider fails to write the message
                         due to some internal error.
MessageNotWriteableException - if the message is in read-only 
                                         mode.
public void writeChar(char value)
               throws JMSException
char to the stream message.
value - the char value to be written
JMSException - if the JMS provider fails to write the message
                         due to some internal error.
MessageNotWriteableException - if the message is in read-only 
                                         mode.
public void writeInt(int value)
              throws JMSException
int to the stream message.
value - the int value to be written
JMSException - if the JMS provider fails to write the message
                         due to some internal error.
MessageNotWriteableException - if the message is in read-only 
                                         mode.
public void writeLong(long value)
               throws JMSException
long to the stream message.
value - the long value to be written
JMSException - if the JMS provider fails to write the message
                         due to some internal error.
MessageNotWriteableException - if the message is in read-only 
                                         mode.
public void writeFloat(float value)
                throws JMSException
float to the stream message.
value - the float value to be written
JMSException - if the JMS provider fails to write the message
                         due to some internal error.
MessageNotWriteableException - if the message is in read-only 
                                         mode.
public void writeDouble(double value)
                 throws JMSException
double to the stream message.
value - the double value to be written
JMSException - if the JMS provider fails to write the message
                         due to some internal error.
MessageNotWriteableException - if the message is in read-only 
                                         mode.
public void writeString(java.lang.String value)
                 throws JMSException
String to the stream message.
value - the String value to be written
JMSException - if the JMS provider fails to write the message
                         due to some internal error.
MessageNotWriteableException - if the message is in read-only 
                                         mode.
public void writeBytes(byte[] value)
                throws JMSException
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.
value - the byte array value to be written
JMSException - if the JMS provider fails to write the message
                         due to some internal error.
MessageNotWriteableException - if the message is in read-only 
                                         mode.
public void writeBytes(byte[] value,
                       int offset,
                       int length)
                throws JMSException
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.
value - the byte array value to be writtenoffset - the initial offset within the byte arraylength - the number of bytes to use
JMSException - if the JMS provider fails to write the message
                         due to some internal error.
MessageNotWriteableException - if the message is in read-only 
                                         mode.
public void writeObject(java.lang.Object value)
                 throws JMSException
This method works only for the objectified primitive
 object types (Integer, Double, 
 Long ...), String objects, and byte 
 arrays.
value - the Java object to be written
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.
public void reset()
           throws JMSException
JMSException - if the JMS provider fails to reset the message
                         due to some internal error.
MessageFormatException - if the message has an invalid
                                   format.| 
 | J2EE1.4 SDK | |||||||||
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Copyright 2003 Sun Microsystems, Inc. All rights reserved.