jrun.jms.core.message
Class BytesMessageImpl

jrun.jms.core.message.BytesMessageImpl

public final class BytesMessageImpl

This class implements the BytesMessage interface

Version:

$Revision: 1.8 $ $Date: 2001/08/06 02:53:21 $

Author:

Jim Mourikis, Tim Anderson

See Also:

BytesMessage

Constructor Summary

BytesMessageImpl()
Construct a new BytesMessage.

Method Summary

void	clearBody() Overide the super class method to reset the streams, and put the message body in write only mode.
java.lang.Object	clone() Clone an instance of this object
boolean	readBoolean() Read a boolean from the bytes message stream
byte	readByte() Read a signed 8-bit value from the bytes message stream
int	readBytes(byte[] value) Read a byte array from the bytes message stream
int	readBytes(byte[] value, int length) Read a portion of the bytes message stream.
char	readChar() Read a Unicode character value from the bytes message stream
double	readDouble() Read a double from the bytes message stream
void	readExternal(java.io.ObjectInput in) Serialize in this message's data
float	readFloat() Read a float from the bytes message stream
int	readInt() Read a signed 32-bit integer from the bytes message stream
long	readLong() Read a signed 64-bit integer from the bytes message stream
short	readShort() Read a signed 16-bit number from the bytes message stream
int	readUnsignedByte() Read an unsigned 8-bit number from the bytes message stream
int	readUnsignedShort() Read an unsigned 16-bit number from the bytes message stream
java.lang.String	readUTF() Read in a string that has been encoded using a modified UTF-8 format from the bytes message stream
void	reset() Put the message body in read-only mode, and reposition the stream of bytes to the beginning
void	setReadOnly(boolean readOnly) Set the read-only mode of the message.
void	writeBoolean(boolean value) Write a boolean to the bytes message stream as a 1-byte value.
void	writeByte(byte value) Write out a byte to the bytes message stream as a 1-byte value
void	writeBytes(byte[] value) Write a byte array to the bytes message stream
void	writeBytes(byte[] value, int offset, int length) Write a portion of a byte array to the bytes message stream
void	writeChar(char value) Write a char to the bytes message stream as a 2-byte value, high byte first.
void	writeDouble(double value) Convert the double argument to a long using the doubleToLongBits method in class Double, and then writes that long value to the bytes message stream as an 8-byte quantity, high byte first.
void	writeExternal(java.io.ObjectOutput out) Serialize out this message's data
void	writeFloat(float value) Convert the float argument to an int using the floatToIntBits method in class Float, and then writes that int value to the bytes message stream as a 4-byte quantity, high byte first.
void	writeInt(int value) Write an int to the bytes message stream as four bytes, high byte first.
void	writeLong(long value) Write a long to the bytes message stream as eight bytes, high byte first
void	writeObject(java.lang.Object value) Write a Java object to the bytes message stream.
void	writeShort(short value) Write a short to the bytes message stream as two bytes, high byte first
void	writeUTF(java.lang.String value) Write a string to the bytes message stream using UTF-8 encoding in a machine-independent manner.

Constructor Detail

BytesMessageImpl

public BytesMessageImpl()
                 throws javax.jms.JMSException

Construct a new BytesMessage. When first created, the message is in write-only mode.

Throws:

JMSException - if the message type can't be set

Method Detail

clone

public final java.lang.Object clone()
                             throws java.lang.CloneNotSupportedException

Clone an instance of this object

Returns:

a copy of this object

Throws:

java.lang.CloneNotSupportedException - if object or attributes aren't cloneable

writeExternal

public final void writeExternal(java.io.ObjectOutput out)
                         throws java.io.IOException

Serialize out this message's data

Parameters:

out - the stream to serialize out to

Throws:

java.io.IOException - if any I/O exceptions occurr

readExternal

public final void readExternal(java.io.ObjectInput in)
                        throws java.lang.ClassNotFoundException,
                               java.io.IOException

Serialize in this message's data

Parameters:

in - the stream to serialize in from

Throws:

java.lang.ClassNotFoundException - if the class for an object being restored cannot be found.

java.io.IOException - if any I/O exceptions occur

readBoolean

public final boolean readBoolean()
                          throws javax.jms.JMSException,
                                 javax.jms.MessageEOFException,
                                 javax.jms.MessageNotReadableException

Read a boolean from the bytes message stream

Returns:

the boolean value read

Throws:

JMSException - if JMS fails to read message due to some internal JMS error

MessageEOFException - if end of bytes stream

MessageNotReadableException - if message is in write-only mode

readByte

public final byte readByte()
                    throws javax.jms.JMSException,
                           javax.jms.MessageEOFException,
                           javax.jms.MessageNotReadableException

Read a signed 8-bit value from the bytes message stream

Returns:

the next byte from the bytes message stream as a signed 8-bit byte

Throws:

JMSException - if JMS fails to read message due to some internal JMS error

MessageEOFException - if end of message stream

MessageNotReadableException - if message is in write-only mode

readUnsignedByte

public final int readUnsignedByte()
                           throws javax.jms.JMSException,
                                  javax.jms.MessageEOFException,
                                  javax.jms.MessageNotReadableException

Read an unsigned 8-bit number from the bytes message stream

Returns:

the next byte from the bytes message stream, interpreted as an unsigned 8-bit number

Throws:

JMSException - if JMS fails to read message due to some internal JMS error

MessageNotReadableException - if message is in write-only mode

MessageEOFException - if end of message stream

readShort

public final short readShort()
                      throws javax.jms.JMSException,
                             javax.jms.MessageEOFException,
                             javax.jms.MessageNotReadableException

Read a signed 16-bit number from the bytes message stream

Returns:

the next two bytes from the bytes message stream, interpreted as a signed 16-bit number

Throws:

JMSException - if JMS fails to read message due to some internal JMS error

MessageEOFException - if end of message stream

MessageNotReadableException - if message is in write-only mode

readUnsignedShort

public final int readUnsignedShort()
                            throws javax.jms.JMSException,
                                   javax.jms.MessageEOFException,
                                   javax.jms.MessageNotReadableException

Read an unsigned 16-bit number from the bytes message stream

Returns:

the next two bytes from the bytes message stream, interpreted as an unsigned 16-bit integer

Throws:

JMSException - if JMS fails to read message due to some internal JMS error

MessageEOFException - if end of message stream

MessageNotReadableException - if message is in write-only mode

readChar

public final char readChar()
                    throws javax.jms.JMSException,
                           javax.jms.MessageEOFException,
                           javax.jms.MessageNotReadableException

Read a Unicode character value from the bytes message stream

Returns:

the next two bytes from the bytes message stream as a Unicode character

Throws:

JMSException - if JMS fails to read message due to some internal JMS error

MessageEOFException - if end of message stream

MessageNotReadableException - if message is in write-only mode

readInt

public final int readInt()
                  throws javax.jms.JMSException,
                         javax.jms.MessageEOFException,
                         javax.jms.MessageNotReadableException

Read a signed 32-bit integer from the bytes message stream

Returns:

the next four bytes from the bytes message stream, interpreted as an int

Throws:

JMSException - if JMS fails to read message due to some internal JMS error

MessageEOFException - if end of message stream

MessageNotReadableException - if message is in write-only mode

readLong

public final long readLong()
                    throws javax.jms.JMSException,
                           javax.jms.MessageEOFException,
                           javax.jms.MessageNotReadableException

Read a signed 64-bit integer from the bytes message stream

Returns:

the next eight bytes from the bytes message stream, interpreted as a long.

Throws:

JMSException - if JMS fails to read message due to some internal JMS error

MessageEOFException - if end of message stream

MessageNotReadableException - if message is in write-only mode

readFloat

public final float readFloat()
                      throws javax.jms.JMSException,
                             javax.jms.MessageEOFException,
                             javax.jms.MessageNotReadableException

Read a float from the bytes message stream

Returns:

the next four bytes from the bytes message stream, interpreted as a float

Throws:

JMSException - if JMS fails to read message due to some internal JMS error

MessageEOFException - if end of message stream

MessageNotReadableException - if message is in write-only mode

readDouble

public final double readDouble()
                        throws javax.jms.JMSException,
                               javax.jms.MessageEOFException,
                               javax.jms.MessageNotReadableException

Read a double from the bytes message stream

Returns:

the next eight bytes from the bytes message stream, interpreted as a double

Throws:

JMSException - if JMS fails to read message due to some internal JMS error

MessageEOFException - if end of message stream

MessageNotReadableException - if message is in write-only mode

readUTF

public final java.lang.String readUTF()
                               throws javax.jms.JMSException,
                                      javax.jms.MessageEOFException,
                                      javax.jms.MessageNotReadableException

Read in a string that has been encoded using a modified UTF-8 format from the bytes message stream

For more information on the UTF-8 format, see "File System Safe UCS Transformation Format (FSS_UFT)", X/Open Preliminary Specification, X/Open Company Ltd., Document Number: P316. This information also appears in ISO/IEC 10646, Annex P.

Returns:

a Unicode string from the bytes message stream

Throws:

JMSException - if JMS fails to read message due to some internal JMS error

MessageEOFException - if end of message stream

MessageNotReadableException - if message is in write-only mode

readBytes

public final int readBytes(byte[] value)
                    throws javax.jms.JMSException,
                           javax.jms.MessageNotReadableException

Read a byte array from the bytes message stream

If the length of array value is less than the bytes remaining to be read from the stream, the array should be filled. A subsequent call reads the next increment, etc.

If the bytes remaining in the stream is less than the length of array value, the bytes should be read into the array. The return value of the total number of bytes read will be less than the length of the array, indicating that there are no more bytes left to be read from the stream. The next read of the stream returns -1.

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

MessageNotReadableException - if message is in write-only mode

readBytes

public final int readBytes(byte[] value,
                           int length)
                    throws javax.jms.JMSException,
                           javax.jms.MessageNotReadableException

Read a portion of the bytes message stream.

If the length of array value is less than the bytes remaining to be read from the stream, the array should be filled. A subsequent call reads the next increment, etc.

If the bytes remaining in the stream is less than the length of array value, the bytes should be read into the array. The return value of the total number of bytes read will be less than the length of the array, indicating that there are no more bytes left to be read from the stream. The next read of the stream returns -1.

If length is negative, or length is greater than the length of the array value, then an IndexOutOfBoundsException is thrown. No bytes will be read from the stream for this exception case.

Parameters:

value - the buffer into which the data is read.

length - the number of bytes to read. Must be less than or equal to value.length.

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:

java.lang.IndexOutOfBoundsException - if length is invalid

JMSException - if JMS fails to read message due to some internal JMS error

MessageNotReadableException - if message is in write-only mode

writeBoolean

public final void writeBoolean(boolean value)
                        throws javax.jms.JMSException,
                               javax.jms.MessageNotWriteableException

Write a boolean to the bytes message stream as a 1-byte value. 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 write message due to some internal JMS error

MessageNotWriteableException - if message is in read-only mode

writeByte

public final void writeByte(byte value)
                     throws javax.jms.JMSException,
                            javax.jms.MessageNotWriteableException

Write out a byte to the bytes message stream as a 1-byte value

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 is in read-only mode

writeShort

public final void writeShort(short value)
                      throws javax.jms.JMSException,
                             javax.jms.MessageNotWriteableException

Write a short to the bytes message stream as two bytes, high byte first

Parameters:

value - the short to be written

Throws:

JMSException - if JMS fails to write message due to some internal JMS error

MessageNotWriteableException - if message is in read-only mode

writeChar

public final void writeChar(char value)
                     throws javax.jms.JMSException,
                            javax.jms.MessageNotWriteableException

Write a char to the bytes message stream as a 2-byte value, high byte first.

Parameters:

value - the char value to be written

Throws:

MessageNotWriteableException - if message is in read-only mode

JMSException - if JMS fails to write message due to some internal JMS error

writeInt

public final void writeInt(int value)
                    throws javax.jms.JMSException,
                           javax.jms.MessageNotWriteableException

Write an int to the bytes message stream as four bytes, high byte first.

Parameters:

value - the int to be written

Throws:

JMSException - if JMS fails to write message due to some internal JMS error

MessageNotWriteableException - if message is in read-only mode

writeLong

public final void writeLong(long value)
                     throws javax.jms.JMSException,
                            javax.jms.MessageNotWriteableException

Write a long to the bytes message stream as eight bytes, high byte first

Parameters:

value - the long to be written

Throws:

JMSException - if JMS fails to write message due to some internal JMS error

MessageNotWriteableException - if message is in read-only mode

writeFloat

public final void writeFloat(float value)
                      throws javax.jms.JMSException,
                             javax.jms.MessageNotWriteableException

Convert the float argument to an int using the floatToIntBits method in class Float, and then writes that int value to the bytes message stream as a 4-byte quantity, high byte first.

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 is in read-only mode

writeDouble

public final void writeDouble(double value)
                       throws javax.jms.JMSException,
                              javax.jms.MessageNotWriteableException

Convert the double argument to a long using the doubleToLongBits method in class Double, and then writes that long value to the bytes message stream as an 8-byte quantity, high byte first.

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 is in read-only mode

writeUTF

public final void writeUTF(java.lang.String value)
                    throws javax.jms.JMSException,
                           javax.jms.MessageNotWriteableException

Write a string to the bytes message stream using UTF-8 encoding in a machine-independent manner.

For more information on the UTF-8 format, see "File System Safe UCS Transformation Format (FSS_UFT)", X/Open Preliminary Specification, X/Open Company Ltd., Document Number: P316. This information also appears in ISO/IEC 10646, Annex P.

Parameters:

value - the String value to be written

Throws:

MessageNotWriteableException - if message is in read-only mode

JMSException - if JMS fails to write message due to some internal JMS error

writeBytes

public final void writeBytes(byte[] value)
                      throws javax.jms.JMSException,
                             javax.jms.MessageNotWriteableException

Write a byte array to the bytes message stream

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 is in read-only mode

writeBytes

public final void writeBytes(byte[] value,
                             int offset,
                             int length)
                      throws javax.jms.JMSException,
                             javax.jms.MessageNotWriteableException

Write a portion of a byte array to the bytes message stream

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 is in read-only mode

writeObject

public final void writeObject(java.lang.Object value)
                       throws javax.jms.JMSException,
                              javax.jms.MessageFormatException,
                              javax.jms.MessageNotWriteableException

Write a Java object to the bytes message stream.

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. Must not be null.

Throws:

JMSException - if JMS fails to write message due to some internal JMS error

MessageFormatException - if object is invalid type

MessageNotWriteableException - if message in read-only mode

NullPointerException - if parameter value is null

reset

public final void reset()
                 throws javax.jms.JMSException

Put the message body in read-only mode, and reposition the stream of bytes to the beginning

Throws:

JMSException - if JMS fails to reset the message due to some internal JMS error

clearBody

public final void clearBody()
                     throws javax.jms.JMSException

Overide 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.

Throws:

JMSException - if JMS fails to reset the message due to some internal JMS error

MessageFormatException - if message has an invalid format

setReadOnly

public final void setReadOnly(boolean readOnly)
                       throws javax.jms.JMSException

Set the read-only mode of the message.

Parameters:

readOnly - if true, make the message body and properties read-only, and invoke reset()

Throws:

JMSException - if the read-only mode cannot be changed