28 lines
743 B
Java
28 lines
743 B
Java
// reuse/FinalArguments.java
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// (c)2017 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://OnJava8.com for more book information.
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// Using "final" with method arguments
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class Gizmo {
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public void spin() {}
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}
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public class FinalArguments {
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void with(final Gizmo g) {
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//- g = new Gizmo(); // Illegal -- g is final
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}
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void without(Gizmo g) {
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g = new Gizmo(); // OK -- g not final
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g.spin();
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}
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// void f(final int i) { i++; } // Can't change
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// You can only read from a final primitive:
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int g(final int i) { return i + 1; }
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public static void main(String[] args) {
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FinalArguments bf = new FinalArguments();
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bf.without(null);
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bf.with(null);
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}
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}
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