OnJava8-Examples/reuse/FinalArguments.java at master · xinan-w/OnJava8-Examples · GitHub

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// reuse/FinalArguments.java

// We make no guarantees that this code is fit for any purpose.

// Visit http://OnJava8.com for more book information.

// Using "final" with method arguments

class Gizmo {

public void spin() {}

}

public class FinalArguments {

void with(final Gizmo g) {

//- g = new Gizmo(); // Illegal -- g is final

}

void without(Gizmo g) {

g = new Gizmo(); // OK -- g not final

g.spin();

}

// void f(final int i) { i++; } // Can't change

// You can only read from a final primitive:

int g(final int i) { return i + 1; }

public static void main(String[] args) {

FinalArguments bf = new FinalArguments();

bf.without(null);

bf.with(null);

}

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