|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Objectorg.apache.activemq.command.BaseCommand
org.apache.activemq.command.Message
org.apache.activemq.command.ActiveMQMessage
org.apache.activemq.command.ActiveMQStreamMessage
public class ActiveMQStreamMessage
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 | |
---|---|
protected ByteArrayOutputStream |
bytesOut
|
static byte |
DATA_STRUCTURE_TYPE
|
protected java.io.DataInputStream |
dataIn
|
protected java.io.DataOutputStream |
dataOut
|
protected int |
remainingBytes
|
Fields inherited from class org.apache.activemq.command.ActiveMQMessage |
---|
acknowledgeCallback |
Fields inherited from class org.apache.activemq.command.Message |
---|
arrival, AVERAGE_MESSAGE_SIZE_OVERHEAD, compressed, content, correlationId, dataStructure, destination, droppable, expiration, groupID, groupSequence, marshalledProperties, messageId, originalDestination, originalTransactionId, persistent, priority, producerId, properties, readOnlyBody, readOnlyProperties, recievedByDFBridge, redeliveryCounter, replyTo, size, targetConsumerId, timestamp, transactionId, type, userID |
Fields inherited from class org.apache.activemq.command.BaseCommand |
---|
commandId, responseRequired |
Fields inherited from interface javax.jms.Message |
---|
DEFAULT_DELIVERY_MODE, DEFAULT_PRIORITY, DEFAULT_TIME_TO_LIVE |
Constructor Summary | |
---|---|
ActiveMQStreamMessage()
|
Method Summary | |
---|---|
protected void |
checkWriteOnlyBody()
|
void |
clearBody()
Clears out the message body. |
Message |
copy()
|
byte |
getDataStructureType()
|
void |
onSend()
Send operation event listener. |
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. |
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 String from the stream message. |
void |
reset()
Puts the message body in read-only mode and repositions the stream of bytes to the beginning. |
java.lang.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(java.lang.Object value)
Writes an object to the stream message. |
void |
writeShort(short value)
Writes a short to the stream message. |
void |
writeString(java.lang.String value)
Writes a String to the stream message. |
Methods inherited from class org.apache.activemq.command.BaseCommand |
---|
copy, getCommandId, getFrom, getTo, isBrokerInfo, isMessage, isMessageAck, isMessageDispatch, isMessageDispatchNotification, isResponse, isResponseRequired, isShutdownInfo, isWireFormatInfo, setCommandId, setFrom, setResponseRequired, setTo |
Methods inherited from class java.lang.Object |
---|
clone, finalize, getClass, 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 |
Field Detail |
---|
public static final byte DATA_STRUCTURE_TYPE
protected transient java.io.DataOutputStream dataOut
protected transient ByteArrayOutputStream bytesOut
protected transient java.io.DataInputStream dataIn
protected transient int remainingBytes
Constructor Detail |
---|
public ActiveMQStreamMessage()
Method Detail |
---|
public Message copy()
copy
in class ActiveMQMessage
public void onSend()
ActiveMQMessage
onSend
in class ActiveMQMessage
public byte getDataStructureType()
getDataStructureType
in interface DataStructure
getDataStructureType
in class ActiveMQMessage
public void clearBody() throws javax.jms.JMSException
If this message body was read-only, calling this method leaves the message body in the same state as an empty body in a newly created message.
clearBody
in interface javax.jms.Message
clearBody
in class ActiveMQMessage
javax.jms.JMSException
- if the JMS provider fails to clear the message body due to
some internal error.public boolean readBoolean() throws javax.jms.JMSException
boolean
from the stream message.
readBoolean
in interface javax.jms.StreamMessage
boolean
value read
javax.jms.JMSException
- if the JMS provider fails to read the message due to some
internal error.
javax.jms.MessageEOFException
- if unexpected end of message stream has been reached.
javax.jms.MessageFormatException
- if this type conversion is invalid.
javax.jms.MessageNotReadableException
- if the message is in write-only mode.public byte readByte() throws javax.jms.JMSException
byte
value from the stream message.
readByte
in interface javax.jms.StreamMessage
byte
javax.jms.JMSException
- if the JMS provider fails to read the message due to some
internal error.
javax.jms.MessageEOFException
- if unexpected end of message stream has been reached.
javax.jms.MessageFormatException
- if this type conversion is invalid.
javax.jms.MessageNotReadableException
- if the message is in write-only mode.public short readShort() throws javax.jms.JMSException
readShort
in interface javax.jms.StreamMessage
javax.jms.JMSException
- if the JMS provider fails to read the message due to some
internal error.
javax.jms.MessageEOFException
- if unexpected end of message stream has been reached.
javax.jms.MessageFormatException
- if this type conversion is invalid.
javax.jms.MessageNotReadableException
- if the message is in write-only mode.public char readChar() throws javax.jms.JMSException
readChar
in interface javax.jms.StreamMessage
javax.jms.JMSException
- if the JMS provider fails to read the message due to some
internal error.
javax.jms.MessageEOFException
- if unexpected end of message stream has been reached.
javax.jms.MessageFormatException
- if this type conversion is invalid
javax.jms.MessageNotReadableException
- if the message is in write-only mode.public int readInt() throws javax.jms.JMSException
readInt
in interface javax.jms.StreamMessage
int
javax.jms.JMSException
- if the JMS provider fails to read the message due to some
internal error.
javax.jms.MessageEOFException
- if unexpected end of message stream has been reached.
javax.jms.MessageFormatException
- if this type conversion is invalid.
javax.jms.MessageNotReadableException
- if the message is in write-only mode.public long readLong() throws javax.jms.JMSException
readLong
in interface javax.jms.StreamMessage
long
javax.jms.JMSException
- if the JMS provider fails to read the message due to some
internal error.
javax.jms.MessageEOFException
- if unexpected end of message stream has been reached.
javax.jms.MessageFormatException
- if this type conversion is invalid.
javax.jms.MessageNotReadableException
- if the message is in write-only mode.public float readFloat() throws javax.jms.JMSException
float
from the stream message.
readFloat
in interface javax.jms.StreamMessage
float
value from the stream message
javax.jms.JMSException
- if the JMS provider fails to read the message due to some
internal error.
javax.jms.MessageEOFException
- if unexpected end of message stream has been reached.
javax.jms.MessageFormatException
- if this type conversion is invalid.
javax.jms.MessageNotReadableException
- if the message is in write-only mode.public double readDouble() throws javax.jms.JMSException
double
from the stream message.
readDouble
in interface javax.jms.StreamMessage
double
value from the stream message
javax.jms.JMSException
- if the JMS provider fails to read the message due to some
internal error.
javax.jms.MessageEOFException
- if unexpected end of message stream has been reached.
javax.jms.MessageFormatException
- if this type conversion is invalid.
javax.jms.MessageNotReadableException
- if the message is in write-only mode.public java.lang.String readString() throws javax.jms.JMSException
String
from the stream message.
readString
in interface javax.jms.StreamMessage
javax.jms.JMSException
- if the JMS provider fails to read the message due to some
internal error.
javax.jms.MessageEOFException
- if unexpected end of message stream has been reached.
javax.jms.MessageFormatException
- if this type conversion is invalid.
javax.jms.MessageNotReadableException
- if the message is in write-only mode.public int readBytes(byte[] value) throws javax.jms.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.
readBytes
in interface javax.jms.StreamMessage
value
- the buffer into which the data is read
javax.jms.JMSException
- if the JMS provider fails to read the message due to some
internal error.
javax.jms.MessageEOFException
- if unexpected end of message stream has been reached.
javax.jms.MessageFormatException
- if this type conversion is invalid.
javax.jms.MessageNotReadableException
- if the message is in write-only mode.readObject()
public java.lang.Object readObject() throws javax.jms.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
.
readObject
in interface javax.jms.StreamMessage
int
, an
Integer
is returned)
javax.jms.JMSException
- if the JMS provider fails to read the message due to some
internal error.
javax.jms.MessageEOFException
- if unexpected end of message stream has been reached.
javax.jms.MessageFormatException
- if this type conversion is invalid.
javax.jms.MessageNotReadableException
- if the message is in write-only mode.readBytes(byte[] value)
public void writeBoolean(boolean value) throws javax.jms.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
.
writeBoolean
in interface javax.jms.StreamMessage
value
- the boolean
value to be written
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void writeByte(byte value) throws javax.jms.JMSException
byte
to the stream message.
writeByte
in interface javax.jms.StreamMessage
value
- the byte
value to be written
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void writeShort(short value) throws javax.jms.JMSException
short
to the stream message.
writeShort
in interface javax.jms.StreamMessage
value
- the short
value to be written
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void writeChar(char value) throws javax.jms.JMSException
char
to the stream message.
writeChar
in interface javax.jms.StreamMessage
value
- the char
value to be written
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void writeInt(int value) throws javax.jms.JMSException
int
to the stream message.
writeInt
in interface javax.jms.StreamMessage
value
- the int
value to be written
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void writeLong(long value) throws javax.jms.JMSException
long
to the stream message.
writeLong
in interface javax.jms.StreamMessage
value
- the long
value to be written
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void writeFloat(float value) throws javax.jms.JMSException
float
to the stream message.
writeFloat
in interface javax.jms.StreamMessage
value
- the float
value to be written
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void writeDouble(double value) throws javax.jms.JMSException
double
to the stream message.
writeDouble
in interface javax.jms.StreamMessage
value
- the double
value to be written
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void writeString(java.lang.String value) throws javax.jms.JMSException
String
to the stream message.
writeString
in interface javax.jms.StreamMessage
value
- the String
value to be written
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void writeBytes(byte[] value) throws javax.jms.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.
writeBytes
in interface javax.jms.StreamMessage
value
- the byte array value to be written
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void writeBytes(byte[] value, int offset, int length) throws javax.jms.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.
writeBytes
in interface javax.jms.StreamMessage
value
- the byte array value to be writtenoffset
- the initial offset within the byte arraylength
- the number of bytes to use
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void writeObject(java.lang.Object value) throws javax.jms.JMSException
This method works only for the objectified primitive object types (Integer
,
Double
, Long
...),
String
objects, and byte arrays.
writeObject
in interface javax.jms.StreamMessage
value
- the Java object to be written
javax.jms.JMSException
- if the JMS provider fails to write the message due to some
internal error.
javax.jms.MessageFormatException
- if the object is invalid.
javax.jms.MessageNotWriteableException
- if the message is in read-only mode.public void reset() throws javax.jms.JMSException
reset
in interface javax.jms.StreamMessage
javax.jms.JMSException
- if an internal error occursprotected void checkWriteOnlyBody() throws javax.jms.MessageNotReadableException
javax.jms.MessageNotReadableException
public java.lang.String toString()
toString
in class BaseCommand
|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |