package com.train; import java.lang.Math; /******************** * java.lang.Object java.lang.Math * static double sqrt(double a)---返回正确舍入的 double 值的正平方根。 * ******************/ class NoSanjiaoException extends RuntimeException{ NoSanjiaoException(String msg) { super(msg); } } public class ExceptionTest { public static void main(String[] args) { Sanj sanj = new Sanj(10,20,30); System.out.println("This Sanj' area is "+sanj.getArea()); sanj.showInfo(); } } class Sanj{ private double x = 0; private double y = 0; private double z = 0; private double cirLength = 0; Sanj(double argX ,double argY, double argZ) throws NoSanjiaoException{ this.x = argX; this.y = argY; this.z = argZ; this.cirLength = this.x + this.y +this.z; if(x+y<=z||x+z<=y||y+z<=x){ throw new NoSanjiaoException("此三边无法构成三角形!"); } } public void showInfo(){ System.out.println("Sanj' x = "+this.x+"; y = "+this.y+"; z = "+this.z); } public double getArea(){ return Math.sqrt(cirLength*(cirLength-x)*(cirLength-y)*(cirLength-z)); } }
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