软件测试（三）——上机使用JUnit进行测试

 使用Junit和 eclemma进行对程序的测试。

程序内容：输入3个整型变量，判断他们是否能构成等边三角形、等腰三角形或一般三角形。

一、安装Junit，Hamcrest和eclemma

直接通过右键项目——Properties——Java Build Path——Libraries——Add External JARs

将junit 和 hamcrest的包导入即可。

eclemma：

help→install new software→add

注意红色的这里不要选，否则会很慢

然后选择EclEmma直接下载安装。安装后重启即可。

二、编写Triangle类

在src文件夹下创建com.Triangle包，然后创建Triangle.java类

package com.Triangle;

public class Triangle {
    public String positiveTest(int a, int b, int c){
        //判断边长是否为正整数
        if(a>0 && b>0 && c>0) return "Passed";
        else{
            String report = "";
            if(a<=0) report+="1st ";
            if(b<=0) report+="2nd ";
            if(c<=0) report+="3rd ";
            report += "Not Positive";
            return report;
        }
    }
    public String canFormTriangle(int a, int b, int c){
        //判断三条边是否能形成三角形
        if(a+b>c && b+c>a && c+a>b) return "Passed";
        else return "Not Triangle";
    }
    public String isoscelesTest(int a, int b, int c){
        //判断是否为等腰三角形
        if(a==b || b==c || c==a) return "Passed";
        else return "Not Isosceles";
    }
    public String equilateralTest(int a, int b, int c){
        //判断是否为等边三角形
        if(a==b && b==c) return "Passed";
        else return "Not Equilateral";
    }
    public String test(int a, int b, int c){
        //完整的测试
        String report="";
        report = positiveTest(a,b,c);
        if(!report.equals("Passed")) return report;
        else{
            report = canFormTriangle(a,b,c);
            if(!report.equals("Passed")) return report;
            else{
                report = isoscelesTest(a,b,c);
                if(!report.equals("Passed")) return "Scalene";
                else{
                    report = equilateralTest(a,b,c);
                    if(!report.equals("Passed")) return "Isosceles";
                    else{
                        return "Equilateral";
                    }
                }
            }
        }
    }
}

二、编写测试类

新建source folder JUnitTest,里面同样创建com.Triangle包。

由于Triangle里面涉及到不止一个方法。因此为每一个方法都创建测试类。

测试类里，用到了@Parameters 进行参数化测试。由于每个使用参数化进行测试的类都只有一套输入参数，因此不能将对多个方法的测试放到同一个类里。

package com.Triangle;

import static org.junit.Assert.*;

import java.util.Arrays;
import java.util.Collection;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;

import com.Triangle.Triangle;

@RunWith(Parameterized.class)
public class IsEquilateralTest {
    //对equilateralTest()进行测试
    private String expected = null;
    private int a;
    private int b;
    private int c;
    private Triangle triangle = null;

    public IsEquilateralTest(int a, int b, int c, String expected) {
        this.a = a;
        this.b = b;
        this.c = c;
        this.expected = expected;
    }

    @Before
    public void setUp() {
        triangle = new Triangle();
    }

    @Parameters
    public static Collection<Object[]> getData() {
        return Arrays.asList(new Object[][] { 
                { 3,3,3,"Passed" }, 
                { 3,5,3,"Not Equilateral" },
                { 4,1,3,"Not Equilateral" } 
                });
    }

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

package com.Triangle;

import static org.junit.Assert.*;

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

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

import com.Triangle.Triangle;

@RunWith(Parameterized.class)
public class IsIsoscelesTest {
    private String expected = null;
    private int a;
    private int b;
    private int c;
    private Triangle triangle = null;

    public IsIsoscelesTest(int a, int b, int c, String expected) {
        this.a = a;
        this.b = b;
        this.c = c;
        this.expected = expected;
    }

    @Before
    public void setUp() {
        triangle = new Triangle();
    }

    @Parameters
    public static Collection<Object[]> getData() {
        return Arrays.asList(new Object[][] { 
                { 3,3,3,"Passed" }, 
                { 3,5,3,"Passed" },
                { 4,1,3,"Not Isosceles" } 
                });
    }

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

package com.Triangle;

import static org.junit.Assert.*;

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

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

import com.Triangle.Triangle;

@RunWith(Parameterized.class)
public class PositiveTest {
    private String expected = null;
    private int a;
    private int b;
    private int c;
    private Triangle triangle = null;

    public PositiveTest(int a, int b, int c, String expected) {
        this.a = a;
        this.b = b;
        this.c = c;
        this.expected = expected;
    }

    @Before
    public void setUp() {
        triangle = new Triangle();
    }

    @Parameters
    public static Collection<Object[]> getData() {
        return Arrays.asList(new Object[][] { 
                { 3,3,3,"Passed" }, 
                { 3,5,3,"Passed" },
                { 4,-1,3,"2nd Not Positive" } 
                });
    }

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

package com.Triangle;

import static org.junit.Assert.*;
import java.util.Arrays;
import java.util.Collection;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;

import com.Triangle.Triangle;

@RunWith(Parameterized.class)
public class TriangleTestCase {
    private String expected = null;
    private int a;
    private int b;
    private int c;
    private Triangle triangle = null;

    public TriangleTestCase(int a, int b, int c, String expected) {
        this.a = a;
        this.b = b;
        this.c = c;
        this.expected = expected;
    }

    @Before
    public void setUp() {
        triangle = new Triangle();
    }

    @Parameters
    public static Collection<Object[]> getData() {
        return Arrays.asList(new Object[][] {
                {-1,1,1,"1st Not Positive"},{0,1,1,"1st Not Positive"},
                {-1,1,1,"1st Not Positive"},{1,0,1,"2nd Not Positive"},
                {1,1,-1,"3rd Not Positive"},{1,1,0,"3rd Not Positive"},
                {-1,-1,1,"1st 2nd Not Positive"},{-1,1,-1,"1st 3rd Not Positive"},{1,-1,-1,"2nd 3rd Not Positive"},
                {-1,-1,-1,"1st 2nd 3rd Not Positive"},
                {1,1,2,"Not Triangle"},{1,2,1,"Not Triangle"},{2,1,1,"Not Triangle"},
                {1,1,3,"Not Triangle"},{1,3,1,"Not Triangle"},{3,1,1,"Not Triangle"},
                {3,4,5,"Scalene"},{6,8,10,"Scalene"},
                {2,2,3,"Isosceles"},{3,2,2,"Isosceles"},{2,3,2,"Isosceles"},
                {3,3,3,"Equilateral"}
                });
    }

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

最后可以创建一个JUnit Test suite类,将上面五个测试类放到一起，统一进行测试。

package com.Triangle;

import org.junit.runner.RunWith;
import org.junit.runners.Suite;
import org.junit.runners.Suite.SuiteClasses;

@RunWith(Suite.class)
@SuiteClasses({ CanFormTriangleTest.class, IsEquilateralTest.class,
        IsIsoscelesTest.class, PositiveTest.class, TriangleTestCase.class })
public class AllTests {

}

三、使用EclEmma进行测试

可以对每个测试类分别进行测试。也就是对每一个方法单独进行测试。

例如，右键canFormTriangleTest.java，选择Coverage As——JUnit Test进行测试

结果：

由于只是对Triangle里的一部分进行测试，所以覆盖率很小

如果是对TriangleTestCase进行测试，那么会发现对Triangle.java覆盖率就达到100%了

最后，通过AllTests测试时，就可以达到对所有测试类的100%覆盖了(除了AllTests之外)