1 public class Text1{  2     public static void main(String[] args){  3         Outter o=new Outter();  4         //第一题-----上面一句代码是外部类的对象实例化  5         System.out.println("第一题：");  6         Outter.B b=o.new B();  7         b.showA();  8         b.showB();  9         //第二题 10         System.out.println("第二题："); 11         Outter.Staff s=o.new Staff(); 12         s.name="李四"; 13         System.out.println(s.name); 14         //第三题-----多态---1 方法重载 2 方法重写 3 对象多态，这里是对象多态 15         System.out.println("第三题："); 16         Outter.Car car=o.new Aodi(); 17         car.changeSpeed(); 18         car=o.new Benchi(); 19         car.changeSpeed(); 20         //第四题-----多态 21         System.out.println("第四题："); 22         Outter.Rect r=o.new PlaintRect(20,10,10,10); 23         System.out.println("周长为："+r.perimeter()); 24         System.out.println("周长为："+r.area()); 25         System.out.println("坐标"+(r.isInside(10,20)==true?"有效":"无效")); 26     } 27 } 28 //外部类 29 class Outter{ 30     //第一题  31     //父类A 32     class A{ 33         public void showA(){ 34             char a[]=new char[26]; 35             for(int i=0,b=‘a‘;i<a.length;i++,b++){ 36                 a[i]=(char)b; 37                 System.out.print(a[i]+" ");                 38             } 39             System.out.println(); 40         } 41     } 42     //子类B继承父类 43     class B extends A{ 44         public void showB(){ 45             char a[]=new char[26]; 46             for(int i=‘A‘;i<a.length+‘A‘;i++){ 47                 a[i-‘A‘]=(char)i; 48                 System.out.print(a[i-‘A‘]+" "); 49             } 50             System.out.println(); 51         }     52     } 53     //第二题 54     //父类Penson 55     class Penson{ 56         protected String name; 57         protected String address; 58         protected String telphone; 59         protected String mail; 60     } 61     //Penson的子类Employee 62     class Employee extends Penson{ 63         protected String office; 64         protected double wage; 65         protected String hiredate; 66     } 67     //Employee的子类Faculty 68     class Faculty extends Employee{ 69         protected String degree; 70         protected String level; 71     } 72     //Employee的子类Staff 73     class Staff extends Employee{ 74         protected String duty; 75     } 76     //第三题 77     //主类Car 78     class Car{ 79         protected String pinPai; 80         protected void changeSpeed(){ 81             System.out.println("呜呜呜......"); 82         } 83     } 84     //子类Aodi继承Car 85     class Aodi extends Car{ 86         private double price; 87         private String xingHao; 88         public double getPrice(){ 89             return price; 90         } 91         public String getXingHao(){ 92             return xingHao; 93         } 94         public void changeSpeed(){ 95             System.out.println("变速卡卡卡......"); 96         } 97     } 98     //子类Benchi继承Car 99     class Benchi extends Car{100         private double price;101         private String xingHao;102         public double getPrice(){103             return price;104         }105         public String getXingHao(){106             return xingHao;107         }108         public void changeSpeed(){109             System.out.println("变速嘟嘟嘟......");110         }111     }112     //第四题113     //矩形类Rect114     abstract class Rect{115         protected int width;116         protected int height;117         Rect(){118             width=0;119             height=0;120         }121         Rect(int width,int height){122             this.width=width;123             this.height=height;124         }125         protected int area(){126             return width*height;127         }128         protected int perimeter(){129             return 2*(width+height);130         }131         public abstract boolean isInside(int x,int y);132     }133     //带坐标的PlaintRect类继承自Rect134     class PlaintRect extends Rect{135         private int startX;136         private int startY;137         PlaintRect(){138             super();139             startX=0;140             startY=0;141         }142         PlaintRect(int width,int height,int startX,int startY){143             super(width,height);144             this.startX=startX;145             this.startY=startY;146         }147         public void setStartX(int startX){148             this.startX=startX;149         }150         public void setStartY(int startY){151             this.startY=startY;152         }153         public int getStartX(){154             return startX;155         }156         public int getStartY(){157             return startY;    158         }159         public boolean isInside(int x,int y){160             if(x>=startX&&x<=(startX+width)&&y<startY&&y>=(startY-height))161             return true;162             return false;163         }164     }165 }