O'Reilly - Java Message Service

}
public void setByteProperty(String name, byte value)
throws JMSException, MessageNotWriteableException;
public long getLongProperty(String name)
throws JMSException, MessageFormatException;
public void setLongPreperty(String name, long value)
throws JMSException, MessageNotWriteableException;
public short getShortProperty(String name)
throws JMSException, MessageFormatException;
public void setShortProperty(String name, short value)
throws JMSException, MessageNotWriteableException;
public Object getObjectProperty(String name)
throws JMSException, MessageFormatException;
public void setObjectProperty(String name, Object value)
throws JMSException, MessageNotWriteableException;
public void clearProperties( )
throws JMSException;
public Enumeration getPropertyNames( )
throws JMSException;
public boolean propertyExists(String name)
throws JMSException;
...
Java Message Service
The following code shows how a JMS client might produce and consume messages with
properties that have primitive values:
// A message producer writes the properties
message.setStringProperty("username","William");
message.setDoubleProperty("Limit", 33456.72);
message.setBooleanProperty("IsApproved",true);
publisher.publish(message);
...
// A message consumer reads the properties
String name = message.getStringProperty("username");
double limit = message.getDoubleProperty("Limit");
boolean isApproved = message.getBooleanProperty("IsApproved");
The Object property methods that are defined in the Message interface
(setObjectProperty( ) and getObjectProperty( )) are also used for properties, but they
don't give you as much functionality as their names suggest. Only the primitive wrappers
that correspond to the allowed primitive types and the String type can be used by the
Object property methods. Attempting to use any other Object type will result in a
javax.jms.MessageFormatException.
Given that the Object methods don't really let you do anything new, why do they exist?
The Object property methods provide more flexibility, letting you write clients that don't
hard-code the property types into the application. JMS publishers can decide at runtime
what form properties should take, and JMS consumers can read the properties and use
reflection to determine the value types at runtime. Here is an example of how the Object
property methods are used to set and access properties in a message:
// A message producer writes the properties
String username = "William";
Double limit = new Double(33456.72);
Boolean isApproved = new Boolean(true);
...
message.setObjectProperty("username",username);
message.setObjectProperty("Limit", limit);
message.setObjectProperty("IsApproved",isApproved);
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