23 lines
568 B
Java
23 lines
568 B
Java
// reuse/Wind.java
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// (c)2016 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://mindviewinc.com/Books/OnJava/ for more book information.
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// Inheritance & upcasting
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class Instrument {
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public void play() {}
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static void tune(Instrument i) {
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// ...
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i.play();
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}
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}
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// Wind objects are instruments
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// because they have the same interface:
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public class Wind extends Instrument {
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public static void main(String[] args) {
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Wind flute = new Wind();
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Instrument.tune(flute); // Upcasting
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}
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}
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