JUnit 4 Demo

1.Maven Dependency

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>org.fool.junit4</groupId>
	<artifactId>junit4</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>junit4</name>
	<url>http://maven.apache.org</url>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
	</properties>

	<dependencies>
		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>4.11</version>
			<scope>test</scope>
		</dependency>
	</dependencies>
</project>

 

2.Project Directory

 

3.src/main/java

Calculator.java

package org.fool.junit4;

public class Calculator
{
	public int add(int a, int b)
	{
		return a + b;
	}

	public int subtract(int a, int b)
	{
		return a - b;
	}

	public int multiply(int a, int b)
	{
		return a * b;
	}

	public int divide(int a, int b) throws Exception
	{
		if (0 == b)
		{
			throw new Exception("除数不能为0");
		}

		return a / b;
	}
}

 

largest.java

package org.fool.junit4;

public class Largest
{
	public int getLargest(int[] array) throws Exception
	{
		if (null == array || 0 == array.length)
		{
			throw new Exception("数组不能为空！");
		}

		int result = array[0];

		for (int i = 0; i < array.length; i++)
		{
			if (result < array[i])
			{
				result = array[i];
			}
		}

		return result;
	}
}

 

4.src/test/java

CalculatorTest.java

package org.fool.junit4;

import static org.junit.Assert.assertEquals;

import org.junit.After;
import org.junit.AfterClass;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;

public class CalculatorTest
{
	private Calculator cal;

	@BeforeClass
	public static void setUpBeforeClass() throws Exception
	{
		System.out.println("globalInit invoked!");
	}

	@AfterClass
	public static void tearDownAfterClass() throws Exception
	{
		System.out.println("globalDestroy invoked！");
	}

	@Before
	public void setUp() throws Exception
	{
		cal = new Calculator();
		System.out.println("before");
	}

	@After
	public void tearDown() throws Exception
	{
		System.out.println("destroy");
	}

	@Test(timeout = 800)
	public void testAdd()
	{
		int result = cal.add(3, 5);

		assertEquals(8, result);
	}

	@Test
	public void testSubtract()
	{
		int result = cal.subtract(1, 6);

		assertEquals(-5, result);
	}

	@Test
	public void testMultiply()
	{
		int result = cal.multiply(5, 9);

		assertEquals(45, result);
	}

	@Test(expected = Exception.class)
	public void testDivide() throws Exception
	{
		cal.divide(1, 0);
	}

}

 

LargestTest.java

package org.fool.junit4;

import static org.junit.Assert.fail;

import org.junit.After;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;

public class LargestTest
{
	private Largest largest;

	@Before
	public void setUp() throws Exception
	{
		largest = new Largest();
	}

	@After
	public void tearDown() throws Exception
	{
	}

	@Test
	public void testGetLargest()
	{
		int[] array = { 1, 9, -10, -20, 23, 34 };

		int result = 0;

		try
		{
			result = largest.getLargest(array);
		}
		catch (Exception ex)
		{
			fail("测试失败");
		}

		Assert.assertEquals(34, result);
	}

	@Test(expected = Exception.class)
	public void testGetLargest2() throws Exception
	{
		largest.getLargest(null);
	}

	@Test(expected = Exception.class)
	// @Ignore("not ready yet")
	public void testGetLargest3() throws Exception
	{
		largest.getLargest(new int[] {});
	}
}

 

ParametersTest.java

package org.fool.junit4;

import static org.junit.Assert.assertEquals;

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;

@RunWith(Parameterized.class)
public class ParametersTest
{
	private int expected;

	private int input1;

	private int input2;

	private Calculator cal;

	@SuppressWarnings("rawtypes")
	@Parameters
	public static Collection prepareData()
	{
		Object[][] object = { { 3, 1, 2 }, { -4, -1, -3 }, { 5, 2, 3 },
				{ 4, -4, 8 } };

		return Arrays.asList(object);
	}

	@Before
	public void setUp()
	{
		cal = new Calculator();
	}

	public ParametersTest(int expected, int input1, int input2)
	{
		this.expected = expected;
		this.input1 = input1;
		this.input2 = input2;
	}

	@Test
	public void testAdd()
	{
		assertEquals(this.expected, cal.add(this.input1, this.input2));
	}
}

 

TestAll.java

package org.fool.junit4;

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

@RunWith(Suite.class)
@Suite.SuiteClasses({ CalculatorTest.class, LargestTest.class,
		ParametersTest.class })
public class TestAll
{

}

 

TestAll2.java

package org.fool.junit4;

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

@RunWith(Suite.class)
@Suite.SuiteClasses(TestAll.class)
public class TestAll2
{

}