37 lines
818 B
Java
37 lines
818 B
Java
// enumerations/PetPatternMatch2.java
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// (c)2021 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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// {NewFeature} Preview in JDK 17
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// Compile with javac flags:
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// --enable-preview --source 17
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package sealedpet;
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import java.util.*;
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sealed interface Pet {
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void feed();
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}
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final class Dog implements Pet {
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@Override public void feed() {}
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void walk() {}
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}
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final class Fish implements Pet {
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@Override public void feed() {}
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void changeWater() {}
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}
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public class PetPatternMatch2 {
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static void careFor(Pet p) {
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switch(p) {
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case Dog d -> d.walk();
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case Fish f -> f.changeWater();
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};
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}
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static void petCare() {
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List.of(new Dog(), new Fish())
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.forEach(p -> careFor(p));
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}
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}
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