O'Reilly - Java Message Service

Appendix C. Message Properties
Java Message Service
Message properties are additional headers that can be assigned to a message. They provide
the application developer or JMS vendor with the ability to attach more information to a
message. The Message interface provides several accessor and mutator methods for reading
and writing properties. Properties can have a String value, or one of several primitive
(boolean, byte, short, int, long, float, double) values. The naming of properties, together
with their values and conversion rules, are strictly defined by JMS.
C.1 Property Names
Properties are name-value pairs. The name, called the identifier, can be just about any
String that is a valid identifier in the Java language. With a couple of exceptions, the rules
that apply to naming a property are the same as those that apply to the naming of variables.
One difference between a JMS property name and a Java variable name is that a property
name can be any length. In addition, property names are prohibited from using one of the
message selector reserved words. These words include: NOT, AND, OR, BETWEEN, LIKE, IN, IS,
NULL, TRUE, and FALSE.
The property names used in JMS-defined properties and provider-specific properties use
predefined prefixes. These prefixes (JMSX and JMS_) may not be used for application
property names.
C.2 Property Values
Property values can be any boolean, byte, short, int, long, float, double, or String. The
javax.jms.Message interface provides accessor and mutator methods for each of these
property value types. Here is the portion of the Message interface definition that shows
these methods:
package javax.jms;
public interface Message {
public String getStringProperty(String name)
throws JMSException, MessageFormatException;
public void setStringProperty(String name, String value)
throws JMSException, MessageNotWriteableException;
public int getIntProperty(String name)
throws JMSException, MessageFormatException;
public void setIntProperty(String name, int value)
throws JMSException, MessageNotWriteableException;
public boolean getBooleanProperty(String name)
throws JMSException, MessageFormatException;
public void setBooleanProperty(String name, boolean value)
throws JMSException, MessageNotWriteableException;
public double getDoubleProperty(String name)
throws JMSException, MessageFormatException;
public void setDoubleProperty(String name, double value)
throws JMSException, MessageNotWriteableException;
public float getFloatProperty(String name)
throws JMSException, MessageFormatException;
public void setFloatProperty(String name, float value)
throws JMSException, MessageNotWriteableException;
public byte getByteProperty(String name)
throws JMSException, MessageFormatException;
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