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The final keyword in Java is used to declare constants. Its effect is to render the affected non-composite variable immutable. Attempts to change the value of a final-qualified variable after it has been initialized result in a compile-time error. Because constants cannot be changed, it is desirable to define only one instance of them for the class; consequently, constants should also be declared with the static modifier. (See guideline DCL04-J. Do not apply public final to public constants whose value might change in the future.)
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