|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: INNER | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
A BytesMessage is used to send a message containing a stream of
uninterpreted bytes. It inherits Message
and adds a bytes
message body. The receiver of the message supplies the interpretation
of the bytes.
It's methods are based largely on those found in
java.io.DataInputStream
and
java.io.DataOutputStream
.
This message type is for client encoding of existing message formats. If possible, one of the other self-defining message types should be used instead.
Although JMS allows the use of message properties with byte messages it is typically not done since the inclusion of properties affects the format.
The primitive types can be written explicitly using methods
for each type. They may also be written generically as objects.
For instance, a call to BytesMessage.writeInt(6)
is
equivalent to BytesMessage.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. 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 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 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.
Session.createBytesMessage()
,
MapMessage
,
Message
,
ObjectMessage
,
StreamMessage
,
TextMessage
Fields inherited from interface javax.jms.Message |
DEFAULT_DELIVERY_MODE,
DEFAULT_PRIORITY,
DEFAULT_TIME_TO_LIVE |
Method Summary | |
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. |
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 |
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 |
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. |
Method Detail |
public boolean readBoolean() throws JMSException
boolean
from the bytes message stream.boolean
value read.public byte readByte() throws JMSException
byte
.public int readUnsignedByte() throws JMSException
public short readShort() throws JMSException
public int readUnsignedShort() throws JMSException
public char readChar() throws JMSException
public int readInt() throws JMSException
int
.public long readLong() throws JMSException
long
.public float readFloat() throws JMSException
float
from the bytes message stream.float
.public double readDouble() throws JMSException
double
from the bytes message stream.double
.public java.lang.String readUTF() throws JMSException
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.
public int readBytes(byte[] value) throws JMSException
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.
value
- the buffer into which the data is read.public int readBytes(byte[] value, int length) throws JMSException
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.
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.public void writeBoolean(boolean value) throws JMSException
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
.value
- the boolean
value to be written.public void writeByte(byte value) throws JMSException
byte
to the bytes message stream as a 1-byte value.value
- the byte
value to be written.public void writeShort(short value) throws JMSException
short
to the bytes message stream as two bytes, high
byte first.value
- the short
to be written.public void writeChar(char value) throws JMSException
char
to the bytes message stream as a 2-byte value,
high byte first.value
- the char
value to be written.public void writeInt(int value) throws JMSException
int
to the bytes message stream as four bytes,
high byte first.value
- the int
to be written.public void writeLong(long value) throws JMSException
long
to the bytes message stream as eight bytes,
high byte first.value
- the long
to be written.public void writeFloat(float value) throws JMSException
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.value
- the float
value to be written.public void writeDouble(double value) throws JMSException
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.value
- the double
value to be written.public void writeUTF(java.lang.String value) throws JMSException
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.
value
- the String
value to be written.public void writeBytes(byte[] value) throws JMSException
value
- the byte array to be written.public void writeBytes(byte[] value, int offset, int length) throws JMSException
value
- the byte array value to be written.offset
- the initial offset within the byte array.length
- the number of bytes to use.public void writeObject(java.lang.Object value) throws JMSException
Note that this method only works for the objectified primitive object types (Integer, Double, Long ...), String's and byte arrays.
value
- the Java object to be written. Must not be null.value
is null.public void reset() throws JMSException
|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: INNER | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |