Spring框架进行Service和DAO单元测试

Spring在J2EE开发中已经应用得十分广泛，在进行实际开发时，往往需要对Service和DAO层进行单元测试。本文基于Spring框架，使用Jnit4进行单元测试。

项目结构主要包括：DAO层接口和实现，Service层接口和实现，配置文件及测试用例。

主要jar包通过maven进行管理，pom.xml关键配置信息如下:

<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/maven-v4_0_0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<groupId>com</groupId>
	<artifactId>mall</artifactId>
	<packaging>war</packaging>
	<version>0.0.1-SNAPSHOT</version>
	<name>springmvc Maven Webapp</name>
	<url>http://maven.apache.org</url>
	<properties>
		<!-- spring版本号 -->
		<spring.version>3.2.5.RELEASE</spring.version>
		<!-- mybatis版本号 -->
		<mybatis.version>3.2.5</mybatis.version>
		<!-- log4j日志文件管理包版本 -->
		<slf4j.version>1.6.6</slf4j.version>
		<log4j.version>1.2.9</log4j.version>
	</properties>
	<dependencies>
		<!-- spring核心包 -->
		<!-- springframe start -->
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-core</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-web</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-oxm</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-tx</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-jdbc</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-webmvc</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-aop</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-context-support</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-aop</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-test</artifactId>
			<version>${spring.version}</version>
		</dependency>
		<!-- springframe end -->
		<!-- junit测试包 -->
		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>4.11</version>
			<scope>test</scope>
		</dependency>
	</dependencies>
	<build>
		<finalName>springmvc</finalName>
	</build>
</project>

 DAO层及实现示例代码：

package com.mall.dao;

public interface TestDAO {
	public void save(String str);
}

 

package com.mall.dao.impl;

import java.util.logging.Logger;

import com.mall.dao.TestDAO;

public class TestDAOImpl implements TestDAO{
	private Logger logger = Logger.getLogger(TestDAO.class.getName());
	
	public void save(String str) {
		logger.info("This is DAO args:"+str);
	}

}

 Service层及实现：

package com.mall.service;

public interface TestService {
	public void save(String str);
}

 

package com.mall.service.impl;

import java.util.logging.Logger;

import com.mall.dao.TestDAO;
import com.mall.service.TestService;

public class TestServiceImpl implements TestService{
	private Logger logger = Logger.getLogger(TestServiceImpl.class.getName());
	private TestDAO dao;
	
	public void save(String str) {
		logger.info("Service entered arg:"+str);
		str = str + " has been modified";
		dao.save(str);
	}
	public void setDao(TestDAO dao) {
		this.dao = dao;
	}

}

 spring容器配置文件：spring-test.xml:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
 xmlns:context="http://www.springframework.org/schema/context"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://www.springframework.org/schema/beans
      http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
      http://www.springframework.org/schema/context
      http://www.springframework.org/schema/context/spring-context.xsd">
      <bean id="TestService" class="com.mall.service.impl.TestServiceImpl">
      	<property name="dao" ref="TestDAO"></property>
      </bean>
	 <bean id="TestDAO" class="com.mall.dao.impl.TestDAOImpl">
	 </bean>
 </beans>

 下面开始编写测试用例，在进行测试之前，需要统一加载配置文件，并提*生Bean的方法，考虑使用以下基础测试类来提供公共测试环境：

package com.mall.util;

import org.junit.After;
import org.junit.Before;
import org.springframework.beans.BeansException;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.util.StringUtils;


public class UnitTestBase {
	private ClassPathXmlApplicationContext context;
	private String springXmlpath;
	public UnitTestBase() {}
	
	public UnitTestBase(String springXmlpath) {
		this.springXmlpath = springXmlpath;
	}
	
	@Before
	public void before() {
		if (StringUtils.isEmpty(springXmlpath)) {
			springXmlpath = "classpath*:spring-*.xml";
		}
		try {
			context = new ClassPathXmlApplicationContext(springXmlpath.split("[,\\s]+"));
			context.start();
		} catch (BeansException e) {
			e.printStackTrace();
		}
	}
	
	@After
	public void after() {
		context.destroy();
	}
	
	@SuppressWarnings("unchecked")
	protected <T extends Object> T getBean(String beanId) {
		try {
			return (T)context.getBean(beanId);
		} catch (BeansException e) {
			e.printStackTrace();
			return null;
		}
	}
	
	protected <T extends Object> T getBean(Class<T> clazz) {
		try {
			return context.getBean(clazz);
		} catch (BeansException e) {
			e.printStackTrace();
			return null;
		}
	}

}

 在书写测试用例时，使用Junit4提供的注解：

package mall.test;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.BlockJUnit4ClassRunner;

import com.mall.service.impl.TestServiceImpl;
import com.mall.util.UnitTestBase;

@RunWith(BlockJUnit4ClassRunner.class)
public class TestInj extends UnitTestBase{
	public TestInj(){
		super("classpath:spring-test.xml");
	}
	@Test
	public void test(){
		TestServiceImpl service = super.getBean("TestService");
		service.save("Idiot.");
	}
}

 将测试用例作为Junit TestCase运行，将看到控制台输出以下内容：

log4j:WARN No appenders could be found for logger (org.springframework.core.env.StandardEnvironment).

log4j:WARN Please initialize the log4j system properly.

十一月 17, 2015 7:37:04 下午 com.mall.service.impl.TestServiceImpl save

INFO: Service entered arg:Idiot.

十一月 17, 2015 7:37:04 下午 com.mall.dao.impl.TestDAOImpl save

INFO: This is DAO args:Idiot. has been modified

表明Service层对DAO层的调用测试通过。

实际开发中，Service层往往具有更为复杂的业务逻辑，而DAO层通常仅负责与数据库进行交互，使用这种测试方法能较好地完成业务层和数据库操作层的单元测试。