O'Reilly - Java Message Service

Java Message Service
Messages come in various types that are defined by the payload they carry. The payload
itself might be very structured, as with StreamMessage and MapMessage objects, or fairly
unstructured, as with TextMessage, ObjectMessage, and BytesMessage types. Messages can
carry important data or simply serve as notifications of events in the system. In most cases,
messages are both notifications and vehicles for carrying data.
The message headers provide metadata about the message describing who or what created
the message, when it was created, how long the data is valid, etc. The headers also contain
routing information that describes the destination of the message (topic or queue), how a
message should be acknowledged, and a lot more. In addition to headers, messages can
carry properties that can be defined and set by the JMS client. JMS consumers can choose
to receive messages based on the values of certain headers and properties, using a special
filtering mechanism called message selectors.
3.1 Headers
Every JMS message has a set of standard headers. Each header is identified by a set of
accessor and mutator methods that follow the idiom setJMS( ), getJMS(
). Here is a partial definition of the Message interface that shows all the JMS header
methods:
public interface Message {
}
public Destination getJMSDestination( ) throws JMSException;
public void setJMSDestination(Destination destination)
throws JMSException;
public int getJMSDeliveryMode( ) throws JMSException;
public void setJMSDeliveryMode(int deliveryMode)
throws JMSException;
public String getJMSMessageID( ) throws JMSException;
public void setJMSMessageID(String id) throws JMSException;
public long getJMSTimestamp( ) throws JMSException;
public void setJMSTimestamp(long timestamp) throws JMSException;
public long getJMSExpiration( ) throws JMSException;
public void setJMSExpiration(long expiration) throws JMSException;
public boolean getJMSRedelivered( ) throws JMSException;
public void setJMSRedelivered(boolean redelivered)
throws JMSException;
public int getJMSPriority( ) throws JMSException;
public void setJMSPriority(int priority) throws JMSException;
public Destination getJMSReplyTo( ) throws JMSException;
public void setJMSReplyTo(Destination replyTo) throws JMSException;
public String getJMSCorrelationID( ) throws JMSException;
public void setJMSCorrelationID(String correlationID)
throws JMSException;
public byte[] getJMSCorrelationIDAsBytes( ) throws JMSException;
public void setJMSCorrelationIDAsBytes(byte[] correlationID)
throws JMSException;
public String getJMSType( ) throws JMSException;
public void setJMSType(String type) throws JMSException;
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