O'Reilly - Java Message Service

Table D.3. Definition of the OR Operator
Expression Result
TRUE OR TRUE TRUE
TRUE OR FALSE TRUE
TRUE OR Unknown TRUE
FALSE OR Unknown Unknown
Unknown OR Unknown Unknown
Table D.4. Definition of the NOT Operator
Expression Result
NOT TRUE FALSE
NOT FALSE TRUE
NOT Unknown Unknown
Java Message Service
To avoid problems, the IS NULL or IS NOT NULL comparison can be used to check for the
existence of a property:
Age IS NULL AND Weight IS NOT NULL
The previous expression selects messages that do not have an Age property but do have a
Weight property.
D.4 Arithmetic Operators
In addition to normal comparison operators, message selectors can use arithmetic operators
to calculate values for evaluation dynamically at runtime. Table D.5 shows the arithmetic
operators in their order of precedence.
Table D.5. Arithmetic Operators
Type Symbol
Unary
Multiplication and division
Addition and subtraction
For example, the following expression applies arithmetic operations to the Age, Height, and
Weight properties to select people who have a weight outside a certain range:
Weight NOT BETWEEN (Age * 5) AND (Height/Age * 2.23)
+, -
*, /
+, -
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