20 lines
398 B
Java
20 lines
398 B
Java
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//: reusing/Wind.java
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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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