Java Message Service, 2nd Edition

Property Value Conversion

The JMS specification defines rules for conversion of property values, so that, for example, a property value of type int can be read as a long:

// Set the property "Age" as an int value
message.setIntProperty("Age", 72);
...
// Read the property "Age" as a long is legal
long age = message.getLongProperty("Age");

The conversion rules are fairly simple, as shown in Table C-1. A property value can be set as one primitive type or String, and read as one of the other value types.

Table C-1. Property type conversions

Message.set<TYPE>Property()	Message.get<TYPE>Property()
boolean	boolean, String
byte	byte, short, int, long, String
short	short, int, long, String
int	int, long, String
long	long, String
float	float, double, String
double	double, String
String	String, boolean, byte, short, int, long, float, double

Each of the accessor methods (get<TYPE>Property()) can throw the MessageFormatException. The MessageFormatException is thrown by the accessor methods to indicate that the original type could not be converted to the type requested. The MessageFormatException might be thrown if, for example, a JMS client attempted to read a float property as an int.

String values can be converted to any primitive type, provided the String is formatted correctly:

Message message = topicSession.createMessage();

// Set the property "Weight" as a String value
message.setStringProperty("Weight","240.00");

// Set the property "IsProgrammer" as a String value
message.setStringProperty("IsProgrammer", ...