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The final keyword in Java is used to declare constants. Its effect is to render the affected variable immutable. Attempting to change the value of a final-qualified variable results in a compile-time error. Since constants cannot be changed, it is desirable to define only one instance of them for the class; hence constants should be declared with the static modifier as well. (DCL31-J. Qualify mathematical constants with the static and final modifiers)
The following code fragment demonstrates the use of static and final to create a constant:
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