37 lines
614 B
Java
37 lines
614 B
Java
package chapter4.example14;
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abstract class Animal {
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abstract void shout();
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}
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class Cat extends Animal {
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public void shout() {
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System.out.println("喵喵...");
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}
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}
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class Dog extends Animal {
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public void shout() {
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System.out.println("汪汪...");
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}
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}
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class Example14 {
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public static void main(String[] args) {
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Animal cat = new Cat();
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Animal dog = new Dog();
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cat.shout();
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dog.shout();
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}
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}
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class Example15 {
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public static void main(String[] args) {
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Dog dog = new Dog();
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Animal an = dog;
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an.shout();
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}
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}
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