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// reusing/Device.java

// TIJ4. Chapter Reusing, Exercise 15, page 260

/* Create a class inside a package. Your class should contain a protected

* method. Outside of the package, try to call the protected method and eplain

* the results. Now inherit from your class and call the protected method from

* inside a method of your derived class.

* Solution incudes reusing/ex15/BasicDevice.java in different package:

* package reusing.ex15;

* public class BasicDevice {

* private String s = "Original";

* public BasicDevice() { s = "Original"; }

* protected void changeS(String c) { // outside package, only derived

* s = c; // classes can access protected method

* }

* public void showS() {

* System.out.println(s);

* }

* }

*/

import reusing.ex15.*;

class DeviceFail {

public static void main(String[] s) {

BasicDevice fail = new BasicDevice();

fail.showS();

// fail.changeS("good-bye"); // cannot access protected method

}

}

public class Device extends BasicDevice {

void changeBasic(String t) {

super.changeS(t); // calls protected method

}

public static void main(String[] args) {

Device d = new Device();

d.showS();

d.changeBasic("Changed"); // derived class can access protected

d.showS();

DeviceFail.main(args);

}

}