O'Reilly - Java Message Service

Java Message Service
Each of the accessor methods (getProperty( )) can throw the
MessageFormatException. The MessageFormatException is thrown by the accessor methods
in order 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", "true");
...
// Read the property "Weight" as a flaot type
float weight = message.getFloatProperty("Weight");
// Read the property "IsProgrammer" as a boolean type
boolean isProgrammer = message.getBooleanProperty("IsProgrammer");
If the String value cannot be converted to the primitive type requested, a
java.lang.NumberFormatException is thrown. Any property can be accessed as a String
using the getStringProperty( ) method; all the primitive types can be converted to a
String value.
The getObjectProperty( ) returns the appropriate object wrapper for that property. For
example, an int can be retrieved by the message consumer as a java.lang.Integer object.
Any property that is set using the setObjectProperty( ) method can also be accessed
using the primitive property accessors; the conversion rules outlined in Table C.1 apply.
The following code shows two properties (Age and Weight) that are set using primitive and
Object property methods. The properties are later accessed using the Object, primitive, and
String accessors:
Message message = topicSession.createMessage( );
// Set the property "Weight" as a float value
message.setFloatProperty("Weight",240.00);
// Set the property "Age" as an Integer value
Integer age = new Integer(72);
message.setObjectProperty("Age", age);
...
// Read the property "Weight" as a java.lang.Float type
Float weight1 = (Float)message.getObjectProperty("Weight");
// Read the property "Weight" as a flaot type
float weight2 = message.getFloatProperty( );
// Read the property "Age" as an Object type
Integer age1 = (Integer)message.getObjectProperty("Age");
// Read the property "Age" as a long is legal
long age2 = message.getLongProperty("Age");
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