写一个Point类，计算两个Point实例之间的距离；写一个判断点是否在圆内的方法。
写一个Point类，计算两个Point实例之间的距离；写一个判断点是否在圆内的方法。2009-07-15 09:02//测试类public class task0714{????? public static void main(String[] args){
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??????????? Point p1 = new Point();
??????????? Point p2 = new Point();
??????????? p1.setX(1);
??????????? p1.setY(1);
??????????? p2.setX(5);
??????????? p2.setY(4);
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??????????? double d = Util.distencePP(p1,p2);
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??????????? System.out.println("点("+p1.getX()+","+p1.getY()+")和点("+p2.getX()+","+p2.getY()+")的距离为："+d);
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??????????? //---------------------------
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??????????? Circle c = new Circle();
??????????? c.setCC(p2);
??????????? c.setR(5);
??????????? String s = Util.distencePC(p1,c);
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??????????? System.out.print("点("+p1.getX()+","+p1.getY()+")在以点("+c.getCC().getX()+","+c.getCC().getY()+")为圆心、半径"+c.getR()+"的"+s);
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????? }}?//计算方法public class Util{
?????? public static double distencePP(Point p1, Point p2){//计算两点之间的距离
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??????????? double d1 = Math.hypot((p1.getX() - p2.getX()),(p1.getY() - p2.getY()));
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??????????? return d1;
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????? }
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????? public static String distencePC(Point p,Circle c){//判断点与圆心之间的距离和圆半径的关系
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??????????? String s ;
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??????????? double d2 = Math.hypot( (p.getX() - c.getCC().getX() ), (p.getY() - c.getCC().getY()) );
??????????? double r = c.getR();
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??????????? if(d2 > r){
??????????? ?
????????????????? s = "圆外";
?????????????????
??????????? }else if(d2 < r){
??????????? ????
??????????? ???? s = "圆内";
??????????? ????
??????????? }else{
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????????????????? s = "圆上";
???????????
??????????? }
???????????
??????????? return s;
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????? }}?//点类public class Point{????? private int x = 0;
????? private int y = 0;
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????? public void setX(int a){
????? ?
????? ???? x = a;
????? ?
????? }
????? public void setY(int b){
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??????????? y = b;
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????? }
????? public int getX(){
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??????????? return x;
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????? }
????? public int getY(){
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??????????? return y;
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????? }
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}?//圆类public class Circle{????? private double r;
????? private Point cc;
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????? public void setR(double a){
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??????????? r = a;
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????? }
????? public void setCC(Point centerOfCir){
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??????????? cc = centerOfCir;
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????? }
????? public double getR(){
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??????????? return r;
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????? }
????? public Point getCC(){
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??????????? return cc;
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????? }}