43 lines
890 B
Java
43 lines
890 B
Java
// staticchecking/dr/DogsAndRobots.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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// {main: staticchecking.dr.DogsAndRobots}
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package staticchecking.dr;
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interface Speaks { void talk(); }
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class Dog implements Speaks {
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public void talk() {
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System.out.println("Woof!");
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}
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public void reproduce() { }
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}
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class Robot implements Speaks {
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public void talk() {
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System.out.println("Click!");
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}
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public void oilChange() { }
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}
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class Communicate {
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public static <T extends Speaks>
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void speak(T speaker) {
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speaker.talk();
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}
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}
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public class DogsAndRobots {
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public static void main(String[] args) {
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Dog d = new Dog();
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Robot r = new Robot();
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Communicate.speak(d);
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Communicate.speak(r);
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}
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}
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/* Output:
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Woof!
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Click!
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*/
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