Java 类和对象7

创建一个三角形类，成员变量三边，方法求周长，创建类主类A来测试它。

public class sanjiaoxing {

    private double a;
    private double b;
    private double c;
    double zhouchang;

    public double getA() {
        return a;
    }

    public void setA(double a) {
        this.a = a;
    }

    public double getB() {
        return b;
    }

    public void setB(double b) {
        this.b = b;
    }

    public double getC() {
        return c;
    }

    public void setC(double c) {
        this.c = c;
    }

    sanjiaoxing(double a, double b, double c) {
        this.a = a;
        this.b = b;
        this.c = c;
    }

    public void getZhouChang() {
        zhouchang = 0;
        if ((a + b > c && a + c > b && b + c > a) && (a >= 0 && b >= 0 && c >= 0)) {
            zhouchang = a + b + c;
        } else {
            System.out.println(this.a + "	" + this.b + "	" + this.c  + "三个数不能构成三角形。");
        }
        if (zhouchang != 0) {
            System.out.println(this.a + "	" + this.b + "	" + this.c  + "三个数成功构成三角形 ，周长=" + zhouchang);
        }
    }

    public static void main(String[] args) {
        sanjiaoxing s1 = new sanjiaoxing(1.4, 2.5, 3);
        s1.getZhouChang();

        sanjiaoxing s2 = new sanjiaoxing(1, 3, 4);
        s2.getZhouChang();

        sanjiaoxing s3 = new sanjiaoxing(1, 5, 5);
        s3.getZhouChang();

        sanjiaoxing s4 = new sanjiaoxing(3, -4, 5);
        s4.getZhouChang();
    }

运行：