2015-09-07 11:44:36 -06:00
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// polymorphism/music/Music2.java
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2015-11-14 16:18:05 -08:00
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// <20>2016 MindView LLC: see Copyright.txt
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2015-06-15 17:47:35 -07:00
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// Overloading instead of upcasting.
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package polymorphism.music;
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class Stringed extends Instrument {
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@Override
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public void play(Note n) {
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2015-11-03 12:00:44 -08:00
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System.out.println("Stringed.play() " + n);
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2015-06-15 17:47:35 -07:00
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}
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}
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class Brass extends Instrument {
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@Override
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public void play(Note n) {
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2015-11-03 12:00:44 -08:00
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System.out.println("Brass.play() " + n);
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2015-06-15 17:47:35 -07:00
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}
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}
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public class Music2 {
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public static void tune(Wind i) {
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i.play(Note.MIDDLE_C);
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}
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public static void tune(Stringed i) {
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i.play(Note.MIDDLE_C);
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}
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public static void tune(Brass i) {
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i.play(Note.MIDDLE_C);
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}
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public static void main(String[] args) {
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Wind flute = new Wind();
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Stringed violin = new Stringed();
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Brass frenchHorn = new Brass();
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tune(flute); // No upcasting
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tune(violin);
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tune(frenchHorn);
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}
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2015-09-07 11:44:36 -06:00
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}
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/* Output:
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2015-06-15 17:47:35 -07:00
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Wind.play() MIDDLE_C
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Stringed.play() MIDDLE_C
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Brass.play() MIDDLE_C
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2015-09-07 11:44:36 -06:00
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*/
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