撰寫一個代表圓的類，其中包括圓心（Point ）和半徑兩個屬性，撰寫setRadius方法對輸入的r 值進行檢測，r為正值則有對應的輸出，r為負值則程式報錯提醒：“圓形的半徑不能為負值”。
uj5u.com熱心網友回復：
public class Circle {private double[] point;
private double radius;
public double[] getPoint() {
return point;
}
public void setPoint(double[] point) {
this.point = point;
}
public double getRadius() {
return radius;
}
public void setRadius(double radius) {
if(radius>0) {
System.out.println("沒問題");
this.radius = radius;
}else {
throw new RuntimeException("圓形的半徑不能為負值");
}
}
public static void main(String[] args) {
Circle circle = new Circle();
//circle.setRadius(7.7);
circle.setRadius(-7.7);
}
}
uj5u.com熱心網友回復：
package practice;
public class Circle {
private double[] point;
private double radius;
public double[] getPoint() {
return point;
}
public void setPoint(double[] point) {
this.point = point;
}
public double getRadius() {
return radius;
}
public void setRadius(double radius) {
if(radius>0) {
System.out.println("沒問題");
this.radius = radius;
}else {
throw new RuntimeException("圓形的半徑不能為負值");
}
}
public static void main(String[] args) {
Circle circle = new Circle();
circle.setRadius(7.7); //大于0沒問題
//circle.setRadius(-7.7); //小于0拋出例外資訊
}
}
uj5u.com熱心網友回復：
Point最要也定義成一個類class Point {
private int x=0;
private int y=0;
public Point() {}
public Point(int x, int y) {this.x=x; this.y=y;}
public Point(Point p) {this.x=p.x; this.y=p.y;}
int getX() {return x;}
int getY() {return y;}
void setX(int x) {this.x=x;}
void setY(int y) {this.y=y;}
}
public class Circle {
private Point center = new Point();
private double radius = 0;
public Circle() {}
public Circle(double radius) {setRadius(radius);}
public Circle(Point center, double radius) {setCenter(center); setRadius(radius);}
public void setRadius(double radius) {
if (radius < 0) {
System.out.println("圓形的半徑不能為負值");
return;
}
this.radius = radius;
}
public void setCenter(Point center) {
if (center==null) return;
this.center = center;
}
public void setCenter(int x, int y) {
setCenter(new Point(x, y));
}
public double getRadius() {return radius;}
public Point getCenter() {return center;}
public static void main(String[] args) {
try {
Circle c = new Circle();
Scanner sc = new Scanner(System.in);
System.out.printf("請輸入圓的半徑：");
double r = sc,nextDouble();
c.setRadius(r);
System.out.printf("圓的半徑為：%.2f\n", c.getRadius());
} catch (Throwable e) {
e.printStackTrace();
}
}
}
轉載請註明出處，本文鏈接：https://www.uj5u.com/houduan/103189.html
標籤：Eclipse
上一篇：process 報錯的問題