Class ActiveMQBytesMessage

  • All Implemented Interfaces:
    BytesMessage, Message, MessageReference, Command, DataStructure, MarshallAware, Message, ScheduledMessage

    public class ActiveMQBytesMessage
    extends ActiveMQMessage
    implements BytesMessage
    A BytesMessage object is used to send a message containing a stream of uninterpreted bytes. It inherits from the Message interface and adds a bytes message body. The receiver of the message supplies the interpretation of the bytes.

    The BytesMessage 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 the JMS API allows the use of message properties with byte messages, they are typically not used, since the inclusion of properties may affect 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. 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 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.

    See Also:
    Session.createBytesMessage(), MapMessage, Message, ObjectMessage, StreamMessage, TextMessage
    • Constructor Detail

      • ActiveMQBytesMessage

        public ActiveMQBytesMessage()
    • Method Detail

      • getJMSXMimeType

        public String getJMSXMimeType()
        Description copied from interface: Message
        Returns the MIME type of this mesage. This can be used in selectors to filter on the MIME types of the different JMS messages, or in the case of BlobMessage it allows you to create a selector on the MIME type of the BLOB body
        Specified by:
        getJMSXMimeType in interface Message
        Overrides:
        getJMSXMimeType in class ActiveMQMessage
      • clearBody

        public void clearBody()
                       throws JMSException
        Clears out the message body. Clearing a message's body does not clear its header values or property entries.

        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.

        Specified by:
        clearBody in interface Message
        Overrides:
        clearBody in class ActiveMQMessage
        Throws:
        JMSException - if the JMS provider fails to clear the message body due to some internal error.
      • getBodyLength

        public long getBodyLength()
                           throws JMSException
        Gets the number of bytes of the message body when the message is in read-only mode. The value returned can be used to allocate a byte array. The value returned is the entire length of the message body, regardless of where the pointer for reading the message is currently located.
        Specified by:
        getBodyLength in interface BytesMessage
        Returns:
        number of bytes in the message
        Throws:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageNotReadableException - if the message is in write-only mode.
        Since:
        1.1
      • readByte

        public byte readByte()
                      throws JMSException
        Reads a signed 8-bit value from the bytes message stream.
        Specified by:
        readByte in interface BytesMessage
        Returns:
        the next byte from the bytes message stream as a signed 8-bit byte
        Throws:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageEOFException - if unexpected end of bytes stream has been reached.
        MessageNotReadableException - if the message is in write-only mode.
      • readUnsignedByte

        public int readUnsignedByte()
                             throws JMSException
        Reads an unsigned 8-bit number from the bytes message stream.
        Specified by:
        readUnsignedByte in interface BytesMessage
        Returns:
        the next byte from the bytes message stream, interpreted as an unsigned 8-bit number
        Throws:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageEOFException - if unexpected end of bytes stream has been reached.
        MessageNotReadableException - if the message is in write-only mode.
      • readShort

        public short readShort()
                        throws JMSException
        Reads a signed 16-bit number from the bytes message stream.
        Specified by:
        readShort in interface BytesMessage
        Returns:
        the next two bytes from the bytes message stream, interpreted as a signed 16-bit number
        Throws:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageEOFException - if unexpected end of bytes stream has been reached.
        MessageNotReadableException - if the message is in write-only mode.
      • readUnsignedShort

        public int readUnsignedShort()
                              throws JMSException
        Reads an unsigned 16-bit number from the bytes message stream.
        Specified by:
        readUnsignedShort in interface BytesMessage
        Returns:
        the next two bytes from the bytes message stream, interpreted as an unsigned 16-bit integer
        Throws:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageEOFException - if unexpected end of bytes stream has been reached.
        MessageNotReadableException - if the message is in write-only mode.
      • readChar

        public char readChar()
                      throws JMSException
        Reads a Unicode character value from the bytes message stream.
        Specified by:
        readChar in interface BytesMessage
        Returns:
        the next two bytes from the bytes message stream as a Unicode character
        Throws:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageEOFException - if unexpected end of bytes stream has been reached.
        MessageNotReadableException - if the message is in write-only mode.
      • readInt

        public int readInt()
                    throws JMSException
        Reads a signed 32-bit integer from the bytes message stream.
        Specified by:
        readInt in interface BytesMessage
        Returns:
        the next four bytes from the bytes message stream, interpreted as an int
        Throws:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageEOFException - if unexpected end of bytes stream has been reached.
        MessageNotReadableException - if the message is in write-only mode.
      • readLong

        public long readLong()
                      throws JMSException
        Reads a signed 64-bit integer from the bytes message stream.
        Specified by:
        readLong in interface BytesMessage
        Returns:
        the next eight bytes from the bytes message stream, interpreted as a long
        Throws:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageEOFException - if unexpected end of bytes stream has been reached.
        MessageNotReadableException - if the message is in write-only mode.
      • readFloat

        public float readFloat()
                        throws JMSException
        Reads a float from the bytes message stream.
        Specified by:
        readFloat in interface BytesMessage
        Returns:
        the next four bytes from the bytes message stream, interpreted as a float
        Throws:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageEOFException - if unexpected end of bytes stream has been reached.
        MessageNotReadableException - if the message is in write-only mode.
      • readDouble

        public double readDouble()
                          throws JMSException
        Reads a double from the bytes message stream.
        Specified by:
        readDouble in interface BytesMessage
        Returns:
        the next eight bytes from the bytes message stream, interpreted as a double
        Throws:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageEOFException - if unexpected end of bytes stream has been reached.
        MessageNotReadableException - if the message is in write-only mode.
      • readUTF

        public String readUTF()
                       throws JMSException
        Reads 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_UTF)", X/Open Preliminary Specification, X/Open Company Ltd., Document Number: P316. This information also appears in ISO/IEC 10646, Annex P.

        Specified by:
        readUTF in interface BytesMessage
        Returns:
        a Unicode string from the bytes message stream
        Throws:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageEOFException - if unexpected end of bytes stream has been reached.
        MessageNotReadableException - if the message is in write-only mode.
      • readBytes

        public int readBytes​(byte[] value)
                      throws JMSException
        Reads a byte array from the bytes message stream.

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

        If the number of 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.

        Specified by:
        readBytes in interface BytesMessage
        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 the JMS provider fails to read the message due to some internal error.
        MessageNotReadableException - if the message is in write-only mode.
      • readBytes

        public int readBytes​(byte[] value,
                             int length)
                      throws JMSException
        Reads a portion of the bytes message stream.

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

        If the number of 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.

        Specified by:
        readBytes in interface BytesMessage
        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:
        JMSException - if the JMS provider fails to read the message due to some internal error.
        MessageNotReadableException - if the message is in write-only mode.
      • writeBoolean

        public void writeBoolean​(boolean value)
                          throws JMSException
        Writes a boolean to the bytes message stream as a 1-byte value. 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 BytesMessage
        Parameters:
        value - the boolean value to be written
        Throws:
        JMSException - if the JMS provider fails to write the message due to some internal error.
        MessageNotWriteableException - if the message is in read-only mode.
      • writeByte

        public void writeByte​(byte value)
                       throws JMSException
        Writes a byte to the bytes message stream as a 1-byte value.
        Specified by:
        writeByte in interface BytesMessage
        Parameters:
        value - the byte value to be written
        Throws:
        JMSException - if the JMS provider fails to write the message due to some internal error.
        MessageNotWriteableException - if the message is in read-only mode.
      • writeShort

        public void writeShort​(short value)
                        throws JMSException
        Writes a short to the bytes message stream as two bytes, high byte first.
        Specified by:
        writeShort in interface BytesMessage
        Parameters:
        value - the short to be written
        Throws:
        JMSException - if the JMS provider fails to write the message due to some internal error.
        MessageNotWriteableException - if the message is in read-only mode.
      • writeChar

        public void writeChar​(char value)
                       throws JMSException
        Writes a char to the bytes message stream as a 2-byte value, high byte first.
        Specified by:
        writeChar in interface BytesMessage
        Parameters:
        value - the char value to be written
        Throws:
        JMSException - if the JMS provider fails to write the message due to some internal error.
        MessageNotWriteableException - if the message is in read-only mode.
      • writeInt

        public void writeInt​(int value)
                      throws JMSException
        Writes an int to the bytes message stream as four bytes, high byte first.
        Specified by:
        writeInt in interface BytesMessage
        Parameters:
        value - the int to be written
        Throws:
        JMSException - if the JMS provider fails to write the message due to some internal error.
        MessageNotWriteableException - if the message is in read-only mode.
      • writeLong

        public void writeLong​(long value)
                       throws JMSException
        Writes a long to the bytes message stream as eight bytes, high byte first.
        Specified by:
        writeLong in interface BytesMessage
        Parameters:
        value - the long to be written
        Throws:
        JMSException - if the JMS provider fails to write the message due to some internal error.
        MessageNotWriteableException - if the message is in read-only mode.
      • writeFloat

        public void writeFloat​(float value)
                        throws JMSException
        Converts 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.
        Specified by:
        writeFloat in interface BytesMessage
        Parameters:
        value - the float value to be written
        Throws:
        JMSException - if the JMS provider fails to write the message due to some internal error.
        MessageNotWriteableException - if the message is in read-only mode.
      • writeDouble

        public void writeDouble​(double value)
                         throws JMSException
        Converts 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.
        Specified by:
        writeDouble in interface BytesMessage
        Parameters:
        value - the double value to be written
        Throws:
        JMSException - if the JMS provider fails to write the message due to some internal error.
        MessageNotWriteableException - if the message is in read-only mode.
      • writeUTF

        public void writeUTF​(String value)
                      throws JMSException
        Writes 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_UTF)", X/Open Preliminary Specification, X/Open Company Ltd., Document Number: P316. This information also appears in ISO/IEC 10646, Annex P.

        Specified by:
        writeUTF in interface BytesMessage
        Parameters:
        value - the String value to be written
        Throws:
        JMSException - if the JMS provider fails to write the message due to some internal error.
        MessageNotWriteableException - if the message is in read-only mode.
      • writeBytes

        public void writeBytes​(byte[] value)
                        throws JMSException
        Writes a byte array to the bytes message stream.
        Specified by:
        writeBytes in interface BytesMessage
        Parameters:
        value - the byte array to be written
        Throws:
        JMSException - if the JMS provider fails to write the message due to some internal error.
        MessageNotWriteableException - if the message is in read-only mode.
      • writeBytes

        public void writeBytes​(byte[] value,
                               int offset,
                               int length)
                        throws JMSException
        Writes a portion of a byte array to the bytes message stream.
        Specified by:
        writeBytes in interface BytesMessage
        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 the JMS provider fails to write the message due to some internal error.
        MessageNotWriteableException - if the message is in read-only mode.
      • writeObject

        public void writeObject​(Object value)
                         throws JMSException
        Writes an object to the bytes message stream.

        This method works only for the objectified primitive object types (Integer,Double, Long  ...), String objects, and byte arrays.

        Specified by:
        writeObject in interface BytesMessage
        Parameters:
        value - the object in the Java programming language ("Java object") to be written; it must not be null
        Throws:
        JMSException - if the JMS provider fails to write the message due to some internal error.
        MessageFormatException - if the object is of an invalid type.
        MessageNotWriteableException - if the message is in read-only mode.
        NullPointerException - if the parameter value is null.
      • reset

        public void reset()
                   throws JMSException
        Puts the message body in read-only mode and repositions the stream of bytes to the beginning.
        Specified by:
        reset in interface BytesMessage
        Throws:
        JMSException - if an internal error occurs