Java类和对象的设计原理

package 作业练习.test2;
public class MyProgram {
public static void main(String[] args) {
Test t1=new Test();
Test t2=new Test();
t1.setStr("A");
t2.setStr("B");
t1.setData(1);
t2.setData(2);
System.out.println(t1.equals(t2));
System.out.println(t1.toString());
System.out.println(t2.toString());
}

}
class Test{
private String str;
private int data;
public String getStr() {
return str;
}
public void setStr(String str) {
this.str = str;
}
public int getData() {
return data;
}
public void setData(int data) {
this.data = data;
}
@Override
public boolean equals(Object object) {
Test test =(Test) object;
if(test.getData()==this.getData()&&test.getStr() == this.getStr()) {
return true;
}
else {
return false;
}
}
@Override
public String toString() {
return "str为"+this.getStr()+"\tdata为："+this.getData();
}
}

package 作业练习.test2;

public class Vehicle {
public float journey;
public int wheelNum;
public int loadNum;
public int driveSpeed;

public Vehicle() {
journey = 100.3f;
wheelNum = 4;
loadNum = 1;
}

public void driveAt(int speed) {
if (speed >= 60) {
System.out.println("行车速度太快，容易造成事故");
driveSpeed = 40;
} else {
System.out.println("你在安全行驶速度内行驶");
driveSpeed = speed;
}
}
}
package 作业练习.test2;
public class Tractor extends Vehicle {
public void plough() {
System.out.println("公里数："+this.journey);
System.out.println("车速："+this.driveSpeed);
System.out.println("承载量："+this.loadNum);
}
public static void main(String[] args) {
Tractor t = new Tractor();
t.plough();
t.driveAt(80);
t.plough();
}
}

package 作业练习.test2;

class Engine extends Car {
String type ;

public void Engine(String type) {
this.type = type;
}

void start() {
System.out.println(type + " starts");
}
}

class Wheel extends Car {
String type ;
int index = 0;

public void Wheel(String type, int index) {
this.type = type;
this.index = index;
}

void roll() {
System.out.println("wheel" + index + " " + type + " rolling");
}
}

public class Car {
String model;
static Wheel[] wheels;
static Engine engine = new Engine();

Car(String model, Wheel[] wheels, String eg) {
this.model = model;
this.wheels = wheels;
engine.Engine(eg);
}
Car() {

}
public void changeWheel(int index, String str) {
wheels[index - 1].Wheel(str, index);
}

void start() {
System.out.println(model + " firing");
engine.start();
for (int i = 0; i < 4; i++) {
wheels[i].roll();
}
}
public static void main(String[] args) {
Wheel[] wheels = new Wheel[4];
String model = "玛莎拉蒂";
String engine = "FSI2.0L";
for (int i = 1; i <= 4; i++) {
wheels[i - 1] = new Wheel();
wheels[i - 1].Wheel("德国马牌", i);
}
Car car = new Car(model, wheels, engine);
car.start();
System.out.println("-----更改轮胎型号-----");
car.changeWheel(2, "米其林");
car.changeWheel(3, "倍耐力");
car.start();
}
}

package 作业练习.test2;
interface Shape {
void draw();
void erase();
}
class Circle implements Shape {
public void draw() {
System.out.println("Circle.draw()");
}
public void erase() {
System.out.println("Circle.erase()");
}
}
class Square implements Shape {
public void draw() {
System.out.println("Square.draw()");
}
public void erase() {
System.out.println("Square.draw()");
}
}
class Triangle implements Shape {
public void draw() {
System.out.println("Triangle.draw()");
}
public void erase() {
System.out.println("Triangle.draw()");
}
}
public class Shapes {
public static Shape randShape() {
switch ((int) (Math.random() * 3)) {
default:
case 0:
return new Circle();
case 1:
return new Square();
case 2:
return new Triangle();
}
}
public static void main(String[] args) {
Shape[] s = new Shape[9];
for (int i = 0; i < s.length; i++)
s[i] = randShape();
for (int i = 0; i < s.length; i++)
s[i].draw();
}
}

package 作业练习.test2.USB接口;
public class Computer {
private USB[] usbArr=new USB[4];
//向计算机上连接一个USB设备
public void add(USB usb){
//遍历所有的插槽
for(int i=0;i<usbArr.length;i++){
//如果发现一个空的
if(usbArr[i]==null){
usbArr[i]=usb;
break;
}
}
}
//计算的开机功能
public void powerOn(){
//遍历所有的插槽
for(int i=0;i<usbArr.length;i++){
//如果发现有设备
if(usbArr[i]!=null){
//将USB设备启动
usbArr[i].turnOn();
}
}
System.out.println("计算机开机成功！！！");
}
//计算的关机功能
public void powerOff(){
//遍历所有的插槽
for(int i=0;i<usbArr.length;i++){
//如果发现有设备
if(usbArr[i]!=null){
//将USB设备关闭
usbArr[i].turnOn();
}
}
System.out.println("计算机关机成功！！！");
}
}

package 作业练习.test2.USB接口;
public class KeyBoard implements USB {
@Override
public void turnOn() {
System.out.println("键盘启动了......");
}
@Override
public void turnOff() {
System.out.println("键盘关闭了......");
}
}

package 作业练习.test2.USB接口;
public class Mic implements USB {
@Override
public void turnOn() {
System.out.println("麦克风启动了......");
}
@Override
public void turnOff() {
System.out.println("麦克风关闭了......");
}
}

package 作业练习.test2.USB接口;
public class Mouse implements USB {
@Override
public void turnOn() {
System.out.println("鼠标启动了......");
}
@Override
public void turnOff() {
System.out.println("鼠标关闭了......");
}
}

package 作业练习.test2.USB接口;
public class Test {
public static void main(String[] args) {
//实例化计算机对象
Computer computer=new Computer();
//向计算机中添加鼠标、麦克风、键盘
computer.add(new Mouse());
computer.add(new Mic());
computer.add(new KeyBoard());
//启动计算机
computer.powerOn();
//关闭计算机
computer.powerOff();

}
}

package 作业练习.test2.USB接口;
public interface USB {
void turnOn();//启动
void turnOff();//关闭
}

class base
{
int a = 100;
}

class sup1 extends base
{
int a = 200;
void show()
{
System.out.println(a);
System.out.println(a);
}
public static void main(String[] args)
{
new sup1().show();
}
}