Class JMSStreamMessage

java.lang.Object

com.ibm.jakarta.jms.JMSMessage

com.ibm.jakarta.jms.JMSStreamMessage

All Implemented Interfaces:

JmsMessage, jakarta.jms.Message, jakarta.jms.StreamMessage, Serializable

public class JMSStreamMessage
extends JMSMessage
implements jakarta.jms.StreamMessage

A StreamMessage is used to send a stream of Java primitives. It is filled and read sequentially. It inherits from JMSMessage 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 can also be read or written generically as objects. For example, 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 the reset() method has been made, the message body is in read-only mode. When a message has been sent, the provider always calls the reset() method to read its content. Likewise, when a message has been received, the provider calls 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.

Stream messages support the following conversion table. The marked cases are supported and the unmarked cases throw a JMSException. The String to primitive conversions throw a runtime exception if the primitives 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 Java primitive type is treated as calling the primitive's corresponding valueOf(String) conversion method with a null value. Because char does not support a String conversion, attempting to read a null value as a char throws a NullPointerException.

To create a stream message please call Session.createStreamMessage(). Do not call the default constructor.

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
static final String	sccsid	The SCCSID which is expanded when the file is extracted from CMVC

Fields inherited from interface jakarta.jms.Message

DEFAULT_DELIVERY_DELAY, DEFAULT_DELIVERY_MODE, DEFAULT_PRIORITY, DEFAULT_TIME_TO_LIVE

Constructor Summary

Constructors

Constructor	Description
JMSStreamMessage()	Deprecated.

Method Summary

Modifier and Type	Method	Description
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 a Java object from the stream message.
short	readShort()	Reads a 16-bit integer from the stream message.
String	readString()	Reads in a String from the stream message.
void	reset()	Puts the message in read-only mode, and repositions the stream to the beginning.
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 to the stream message.
void	writeBytes(byte[] value, int offset, int length)	Writes a portion of a byte array 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 a Java object to the stream message.
void	writeShort(short value)	Write a short to the stream message.
void	writeString(String value)	Writes a String to the stream message.

Methods inherited from class JMSMessage

acknowledge, clearBody, clearProperties, getBody, getBooleanProperty, getByteProperty, getDoubleProperty, getFloatProperty, getIntProperty, getJMSCorrelationID, getJMSCorrelationIDAsBytes, getJMSDeliveryMode, getJMSDeliveryTime, getJMSDestination, getJMSExpiration, getJMSMessageID, getJMSPriority, getJMSRedelivered, getJMSReplyTo, getJMSTimestamp, getJMSType, getLongProperty, getObjectProperty, getPropertyNames, getShortProperty, getStringProperty, isBodyAssignableTo, propertyExists, setBooleanProperty, setByteProperty, setDoubleProperty, setFloatProperty, setIntProperty, setJMSCorrelationID, setJMSCorrelationIDAsBytes, setJMSDeliveryMode, setJMSDeliveryTime, setJMSDestination, setJMSExpiration, setJMSMessageID, setJMSPriority, setJMSRedelivered, setJMSReplyTo, setJMSTimestamp, setJMSType, setLongProperty, setObjectProperty, setShortProperty, setStringProperty, toString, updateFromMessage

Methods inherited from class Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface JmsMessage

getDelegate

Methods inherited from interface jakarta.jms.Message

acknowledge, clearBody, clearProperties, getBody, getBooleanProperty, getByteProperty, getDoubleProperty, getFloatProperty, getIntProperty, getJMSCorrelationID, getJMSCorrelationIDAsBytes, getJMSDeliveryMode, getJMSDeliveryTime, getJMSDestination, getJMSExpiration, getJMSMessageID, getJMSPriority, getJMSRedelivered, getJMSReplyTo, getJMSTimestamp, getJMSType, getLongProperty, getObjectProperty, getPropertyNames, getShortProperty, getStringProperty, isBodyAssignableTo, propertyExists, setBooleanProperty, setByteProperty, setDoubleProperty, setFloatProperty, setIntProperty, setJMSCorrelationID, setJMSCorrelationIDAsBytes, setJMSDeliveryMode, setJMSDeliveryTime, setJMSDestination, setJMSExpiration, setJMSMessageID, setJMSPriority, setJMSRedelivered, setJMSReplyTo, setJMSTimestamp, setJMSType, setLongProperty, setObjectProperty, setShortProperty, setStringProperty

Field Details

sccsid

public static final String sccsid

The SCCSID which is expanded when the file is extracted from CMVC

See Also:

• Constant Field Values

Constructor Details

JMSStreamMessage

public JMSStreamMessage()

Deprecated.

To create a stream message please call Session.createStreamMessage().

Do not call this default constructor.

Method Details

readBoolean

public boolean readBoolean()
                    throws jakarta.jms.JMSException

Reads a boolean from the stream message.

Specified by:

readBoolean in interface jakarta.jms.StreamMessage

Returns:

the boolean value read

Throws:

jakarta.jms.JMSException - if JMS fails to read the message due to an internal JMS error

jakarta.jms.MessageEOFException - if an end of message stream

jakarta.jms.MessageFormatException - if this type conversion is not valid

jakarta.jms.MessageNotReadableException - if the message is in write-only mode

readByte

public byte readByte()
              throws jakarta.jms.JMSException

Reads a byte value from the stream message.

Specified by:

readByte in interface jakarta.jms.StreamMessage

Returns:

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

Throws:

jakarta.jms.JMSException - if JMS fails to read the message due to an internal JMS error

jakarta.jms.MessageEOFException - if an end of message stream

jakarta.jms.MessageFormatException - if this type conversion is not valid

jakarta.jms.MessageNotReadableException - if the message is in write-only mode

readBytes

public int readBytes(byte[] value)
              throws jakarta.jms.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 values of the bytes in the buffer following the last byte read are 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 will return -1.

If the bytes array field value is null, readBytes() returns -1.

If the bytes array field value is empty, readBytes() returns 0.

After the first readBytes() call on a byte[] field value has been made, the full value of the field must be read before the next field can be read. An attempt to read the next field before that has been done will throw a MessageFormatException.

Specified by:

readBytes in interface jakarta.jms.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:

jakarta.jms.JMSException - if JMS fails to read the message due to an internal JMS error

jakarta.jms.MessageEOFException - if an end of message stream

jakarta.jms.MessageFormatException - if this type conversion is not valid

jakarta.jms.MessageNotReadableException - if the message is in write-only mode

readChar

public char readChar()
              throws jakarta.jms.JMSException

Reads a Unicode character value from the stream message.

Specified by:

readChar in interface jakarta.jms.StreamMessage

Returns:

a Unicode character from the stream message

Throws:

jakarta.jms.JMSException - if JMS fails to read the message due to an internal JMS error

jakarta.jms.MessageEOFException - if an end of message stream

jakarta.jms.MessageFormatException - if this type conversion is not valid

jakarta.jms.MessageNotReadableException - if the message is in write-only mode

readDouble

public double readDouble()
                  throws jakarta.jms.JMSException

Reads a double from the stream message.

Specified by:

readDouble in interface jakarta.jms.StreamMessage

Returns:

a double value from the stream message

Throws:

jakarta.jms.JMSException - if JMS fails to read the message due to an internal JMS error

jakarta.jms.MessageEOFException - if an end of message stream

jakarta.jms.MessageFormatException - if this type conversion is not valid

jakarta.jms.MessageNotReadableException - if the message is in write-only mode

readFloat

public float readFloat()
                throws jakarta.jms.JMSException

Reads a float from the stream message.

Specified by:

readFloat in interface jakarta.jms.StreamMessage

Returns:

a float value from the stream message

Throws:

jakarta.jms.JMSException - if JMS fails to read the message due to an internal JMS error

jakarta.jms.MessageEOFException - if an end of message stream

jakarta.jms.MessageFormatException - if this type conversion is not valid

jakarta.jms.MessageNotReadableException - if the message is in write-only mode

readInt

public int readInt()
            throws jakarta.jms.JMSException

Reads a 32-bit integer from the stream message.

Specified by:

readInt in interface jakarta.jms.StreamMessage

Returns:

a 32-bit integer value from the stream message, interpreted as an int

Throws:

jakarta.jms.JMSException - if JMS fails to read the message due to an internal JMS error

jakarta.jms.MessageEOFException - if an end of message stream

jakarta.jms.MessageFormatException - if this type conversion is not valid

jakarta.jms.MessageNotReadableException - if the message is in write-only mode

readLong

public long readLong()
              throws jakarta.jms.JMSException

Reads a 64-bit integer from the stream message.

Specified by:

readLong in interface jakarta.jms.StreamMessage

Returns:

a 64-bit integer value from the stream message, interpreted as a long

Throws:

jakarta.jms.JMSException - if JMS fails to read the message due to an internal JMS error

jakarta.jms.MessageEOFException - if an end of message stream

jakarta.jms.MessageFormatException - if this type conversion is not valid

jakarta.jms.MessageNotReadableException - if the message is in write-only mode

readObject

public Object readObject()
                  throws jakarta.jms.JMSException

Reads a Java object from the stream message.

This method can be used to return an object that had been written to the stream with the equivalent writeObject() method call, or its equivalent primitive write<type>() method. It will return one of the primitive object wrapper classes (Integer, Double, Long ...), a String, or a byte array.

Specified by:

readObject in interface jakarta.jms.StreamMessage

Returns:

a Java object from the stream message

Throws:

jakarta.jms.JMSException - if JMS fails to read the message due to an internal JMS error

jakarta.jms.MessageEOFException - if an end of message stream

jakarta.jms.MessageNotReadableException - if the message is in write-only mode

readShort

public short readShort()
                throws jakarta.jms.JMSException

Reads a 16-bit integer from the stream message.

Specified by:

readShort in interface jakarta.jms.StreamMessage

Returns:

a 16-bit integer from the stream message

Throws:

jakarta.jms.JMSException - if JMS fails to read the message due to an internal JMS error

jakarta.jms.MessageEOFException - if an end of message stream

jakarta.jms.MessageFormatException - if this type conversion is not valid

jakarta.jms.MessageNotReadableException - if the message is in write-only mode

readString

public String readString()
                  throws jakarta.jms.JMSException

Reads in a String from the stream message.

Specified by:

readString in interface jakarta.jms.StreamMessage

Returns:

a Unicode string from the stream message

Throws:

jakarta.jms.JMSException - if JMS fails to read the message due to an internal JMS error

jakarta.jms.MessageEOFException - if an end of message stream

jakarta.jms.MessageFormatException - if this type conversion is not valid

jakarta.jms.MessageNotReadableException - if the message is in write-only mode

reset

public void reset()
           throws jakarta.jms.JMSException

Puts the message in read-only mode, and repositions the stream to the beginning.

Specified by:

reset in interface jakarta.jms.StreamMessage

Throws:

jakarta.jms.JMSException - if JMS fails to reset the message due to an internal JMS error

jakarta.jms.MessageFormatException - if the message's format is not valid

writeBoolean

public void writeBoolean(boolean value)
                  throws jakarta.jms.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 jakarta.jms.StreamMessage

Parameters:

value - the boolean value to be written

Throws:

jakarta.jms.JMSException - if JMS fails to write the boolean to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode

writeByte

public void writeByte(byte value)
               throws jakarta.jms.JMSException

Writes a byte to the stream message.

Specified by:

writeByte in interface jakarta.jms.StreamMessage

Parameters:

value - the byte value to be written

Throws:

jakarta.jms.JMSException - if JMS fails to write the byte to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode

writeBytes

public void writeBytes(byte[] value)
                throws jakarta.jms.JMSException

Writes a byte array to the stream message.

Specified by:

writeBytes in interface jakarta.jms.StreamMessage

Parameters:

value - the byte array to be written

Throws:

jakarta.jms.JMSException - if JMS fails to write the byte array to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode

writeBytes

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

Writes a portion of a byte array to the stream message.

Specified by:

writeBytes in interface jakarta.jms.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:

jakarta.jms.JMSException - if JMS fails to write the byte array portion to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode

writeChar

public void writeChar(char value)
               throws jakarta.jms.JMSException

Writes a char to the stream message.

Specified by:

writeChar in interface jakarta.jms.StreamMessage

Parameters:

value - the char value to be written

Throws:

jakarta.jms.JMSException - if JMS fails to write the char to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode

writeDouble

public void writeDouble(double value)
                 throws jakarta.jms.JMSException

Writes a double to the stream message.

Specified by:

writeDouble in interface jakarta.jms.StreamMessage

Parameters:

value - the double value to be written

Throws:

jakarta.jms.JMSException - if JMS fails to write the double to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode

writeFloat

public void writeFloat(float value)
                throws jakarta.jms.JMSException

Writes a float to the stream message.

Specified by:

writeFloat in interface jakarta.jms.StreamMessage

Parameters:

value - the float value to be written

Throws:

jakarta.jms.JMSException - if JMS fails to write the float to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode

writeInt

public void writeInt(int value)
              throws jakarta.jms.JMSException

Writes an int to the stream message.

Specified by:

writeInt in interface jakarta.jms.StreamMessage

Parameters:

value - the int to be written

Throws:

jakarta.jms.JMSException - if JMS fails to write the int to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode

writeLong

public void writeLong(long value)
               throws jakarta.jms.JMSException

Writes a long to the stream message.

Specified by:

writeLong in interface jakarta.jms.StreamMessage

Parameters:

value - the long to be written

Throws:

jakarta.jms.JMSException - if JMS fails to write the long to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode

writeObject

public void writeObject(Object value)
                 throws jakarta.jms.JMSException

Writes a Java object to the stream message.

This method only works for the primitive object wrapper classes (Integer, Double, Long ...), Strings and byte arrays.

Specified by:

writeObject in interface jakarta.jms.StreamMessage

Parameters:

value - the Java object to be written

Throws:

jakarta.jms.JMSException - if JMS fails to write the object to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode.

jakarta.jms.MessageFormatException - if the object is not valid

writeShort

public void writeShort(short value)
                throws jakarta.jms.JMSException

Write a short to the stream message.

Specified by:

writeShort in interface jakarta.jms.StreamMessage

Parameters:

value - the short to be written

Throws:

jakarta.jms.JMSException - if JMS fails to write the short to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode

writeString

public void writeString(String value)
                 throws jakarta.jms.JMSException

Writes a String to the stream message.

Specified by:

writeString in interface jakarta.jms.StreamMessage

Parameters:

value - the String value to be written

Throws:

jakarta.jms.JMSException - if JMS fails to write the String to the message due to an internal JMS error

jakarta.jms.MessageNotWriteableException - if the message is in read-only mode