Triangle Problem

songxiuhuan 宋修寰

Import the Junit and eclemma

Choose the project and right click, choose the build path and choose the Junit and hamcrest.

Install eclemma

Help——install newsoftware——input the URL of the eclemma in my PC

Coding the triangle and testTriangle, to verify if it’s a triangle and equilateral, isosceles, or scalene.

When a==b==c it’s a equilateral one.

When a==b!=c it’s a isosceles one.

Others they are scalene.

KEY: A regular triangle must obey that a+b>c and a-b<c. Or there will be a failure.

package testTriangle;

import static org.junit.Assert.*;

import java.util.Arrays;
import java.util.Collection;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;

import triangle.triangle;

@RunWith(Parameterized.class)
public class testTriangle {

    private int a;
    private int b;
    private int c;
    private String expected;
    public testTriangle(int a,int b, int c, String expected){
        this.a = a;
        this.b = b;
        this.c = c;
        this.expected= expected;

        }

    @Parameters
    public static Collection<Object[]> getData(){
    return Arrays.asList(new Object[][]{
    {3,3,3,"equilateral"},
    {1,2,3,"scalene"},
    {5,5,7,"isosceles"},
    {4,6,6,"isosceles"}
    });
    }

    @Test
    public void test() {
    assertEquals(this.expected,triangle.triangleshape(a,b,c));
    }

}

package triangle;

public class triangle {

    public static String triangleshape(int a,int b, int c){
        if( (a + b) < c||(a - b) > c){
            return "error";
        }//判断是否符合三角形三条边的情况，即两边之和大于第三边，两边之差小于第三边；
        if(a == b && a == c && b == c){
            return "equilateral";
        }//三条边相等即为等边三角形
        else if(a == b || a == c || b == c){
            return "isosceles";
        }//任意两边相等即为等腰三角形，并且等边三角形也是等腰三角形
        else{
            return "scalene";
        }//否则为不等边三角形

        }

}