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Trail: Learning the Java Language
Lesson: Language Basics

## Final Variables

> You can declare a variable in any scope to be final, including parameters to methods and constructors. The value of a final variable cannot change after it has been initialized.

> To declare a final variable, use the `final` keyword in the variable declaration before the type:

> >     final int aFinalVar = 0;

> The previous statement declares a final variable and initializes it, all at once. Subsequent attempts to assign a value to `aFinalVar` result in a compiler error. You may, if necessary, defer initialization of a final local variable. Simply declare the local variable and initialize it later, like this:

> >     final int blankfinal;
> >     . . .
> >     blankfinal = 0;

> A final local variable that has been declared but not yet initialized is called a blank final. Again, once a final local variable has been initialized it cannot be set and any later attempts to assign a value to `blankfinal` result in a compile-time error.

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