Java筆記丨11-1 toString方法
摘自高等教育出版社《Java程式設計(許滿武 主編)》
為方便測試,通常在類中實現一個toString方法,把當前物件轉化成一個字串以便顯示
public String toString(){
return ......
}
示例:
class Point{
public double x,y;
public static Point origin=new Point();
Point(double x,double y){
this.x=x;
this.y=y;
}
Point(){}
public void clear(){
x=0;
y=0;
}
public double distance(Point that){
double xdiff,ydiff;
xdiff=x-that.x;
ydiff=y-that.y;
return Math.sqrt(xdiff*xdiff+ydiff*ydiff);
}
public String toString(){
return "x="+x+",y="+y;
}
public static double distance(Point p1,Point p2){
double xdiff,ydiff;
xdiff=p1.x-p2.x;
ydiff=p1.y-p2.y;
return Math.sqrt(xdiff*xdiff+ydiff*ydiff);
}
public static void main(String[] args){
Point A=new Point(1,1);
Point B=new Point(2,2);
System.out.println(B);
}
}
顯示:x=2.0,y=2.0