作业
1.
public class Test01 {
public static void main(String[] args) {
JuiceMachine jm = new JuiceMachine();
Apple a = new Apple();
jm.makeJuice(a);
Orange o = new Orange();
jm.makeJuice(o);
Banana b = new Banana();
jm.makeJuice(b);
}
}
//榨汁机类
class JuiceMachine{
//多态的使用,传入参数
public void makeJuice(Fruit f) {
f.flow();
}
}
//抽象水果类
abstract class Fruit {
public abstract void flow();
}
//橘子类
class Orange extends Fruit{
public void flow() {
System.out.println("流出橙汁");
}
}
//苹果类
class Apple extends Fruit{
public void flow() {
System.out.println("流出苹果汁");
}
}
//香蕉类
class Banana extends Fruit{
public void flow() {
System.out.println("流出香蕉酱");
}
}
2.
public class Test02 {
public static void main(String[] args) {
Object[] object = new Object[5];
Rectangle r1 = new Rectangle(2,3);
Rectangle r2 = new Rectangle(2,3);
Triangle t1 = new Triangle(3,4,5);
Triangle t2 = new Triangle(6,8,10);
Circle c1 = new Circle(4);
object[0] = r1;object[1] = r2;object[2] = t1;
object[3] = t2;object[4] = c1;
double sum = 0;
for(int n = 0; n < object.length; n++) {
if(object[n] instanceof Rectangle ) {
Rectangle r = (Rectangle)object[n];
sum += r.area();
}else if(object[n] instanceof Circle) {
Circle c = (Circle)object[n];
sum += c.area();
}else if(object[n] instanceof Triangle) {
Triangle t = (Triangle)object[n];
sum += t.area();
}
}
System.out.println(sum);
}
}
//形状类
abstract class Shape{
//计算面积的抽象方法
public abstract double area();
}
//矩形类
class Rectangle extends Shape{
double length;
double width;
public Rectangle(double length, double width) {
super();
this.length = length;
this.width = width;
}
public double area() {
return length*width;
}
}
//圆形类
class Circle extends Shape{
double radius;
public Circle(double radius) {
super();
this.radius = radius;
}
public double area() {
return Math.PI*Math.pow(radius, 2);
}
}
//三角形类
class Triangle extends Shape{
double long1;
double long2;
public Triangle(double long1, double long2, double long3) {
super();
this.long1 = long1;
this.long2 = long2;
this.long3 = long3;
}
double long3;
public double area() {
double sum = (long1 + long2 + long3)/2;
return Math.sqrt(sum*(sum-long1)*(sum-long2)*(sum-long3));
}
}
3.
public class Test03 {
public static void main(String[] args) {
Programmer p = new Programmer("熊落落",2016034,15000,3000);
p.work();
p.show();
Tester t = new Tester("李鹏鹏",2016035,17000);
t.work();
t.show();
Manager m = new Manager("崔美娟",2016036,30000,6000);
m.work();
m.show();
}
}
//抽象类 雇员类
abstract class Employee{
String name;
int id;
double salary;
//抽象方法work()
public abstract void work();
//抽象方法show()
public abstract void show();
}
//程序员类
class Programmer extends Employee{
double bonus;
public void work() {
System.out.println("软件开发");
}
public Programmer() {}
public Programmer(String name,int id, double salary,double bonus) {
super();
this.name = name;
this.id = id;
this.salary = salary;
this.bonus = bonus;
}
public void show() {
System.out.println("姓名为" + name + " 工号为" + id+ " 工资为" + salary+ " 奖金为" + bonus);
}
}
//测试工程师类
class Tester extends Employee{
public void work() {
System.out.println("软件测试");
}
public Tester() {}
public Tester(String name,int id, double salary) {
super();
this.name = name;
this.id = id;
this.salary = salary;
}
public void show() {
System.out.println("姓名为" + name + " 工号为" + id+ " 工资为" + salary);
}
}
//项目经理类
class Manager extends Employee{
double bonus;
public Manager() {}
public Manager(String name,int id, double salary,double bonus) {
super();
this.name = name;
this.id = id;
this.salary = salary;
this.bonus = bonus;
}
public void work() {
System.out.println("控制进度");
}
public void show() {
System.out.println("姓名为" + name + " 工号为" + id+ " 工资为" + salary+ " 奖金为" + bonus);
}
}
4.
public class Test04 {
public static void main(String[] args) {
MyCircle mc = new MyCircle(4);
double area1 = mc.calculateArea();
System.out.println(String.format("%.2f", area1));
MyRectangle mr = new MyRectangle(3,4);
double area2 = mr.calculateArea();
System.out.println(area2);
}
}
//接口Area
interface Area{
public abstract double calculateArea();
}
//MyCircle类
class MyCircle implements Area{
double radius;
public double calculateArea() {
return Math.PI*Math.pow(radius, 2);
}
public MyCircle() {
super();
// TODO Auto-generated constructor stub
}
public MyCircle(double radius) {
super();
this.radius = radius;
}
}
//MyRectangle类
class MyRectangle implements Area{
double longth;
double width;
public MyRectangle() {
super();
// TODO Auto-generated constructor stub
}
public MyRectangle(double longth, double width) {
super();
this.longth = longth;
this.width = width;
}
public double calculateArea() {
return longth*width;
}
}
5 .
public class Test05 {
public static void main(String[] args) {
System.out.println("三角形:");
Triangle t = new Triangle();
test(t);
System.out.println("长方形:");
Rectangle r = new Rectangle();
test(r);
System.out.println("菱形:");
Diamond d = new Diamond();
test(d);
}
public static void test(Shape shape) {
if(shape instanceof Triangle) {
Triangle t = (Triangle)shape;
t.draw();
}else if(shape instanceof Rectangle) {
Rectangle r = (Rectangle)shape;
r.draw();
}else if (shape instanceof Diamond) {
Diamond d = (Diamond)shape;
d.draw();
}
}
}
//Shape接口
interface Shape{
public abstract void draw();
}
//Triangle类
class Triangle implements Shape{
public void draw() {
for(int n1 = 1; n1 <= 3; n1++) {
for(int n2 = 3-n1; n2 > 0;n2--) {
System.out.print(" ");
}
for(int n3 = 1; n3 <= 2*n1-1; n3++) {
System.out.print("*");
}
System.out.println();
}
}
}
//Rectangle类
class Rectangle implements Shape{
public void draw() {
for(int n1 = 1; n1 <= 3;n1++)
{
for(int n2 = 1; n2 <= 4;n2++)
{
System.out.print("*");
}
System.out.println();
}
}
}
//Diamond类
class Diamond implements Shape{
public void draw() {
for(int n1 = 1; n1 <= 2; n1++) {
for(int n2 = 2-n1; n2 > 0; n2--) {
System.out.print(" ");
}
for(int n3 = 1; n3 <= 2*n1-1;n3++) {
System.out.print("*");
}
System.out.println();
}
System.out.println(" *");
}
}
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