【Junit】Junit 与 Spring 整合测试

　　本章介绍使用 Junit4 测试 Spring，关于 Junit4 的基本使用 参考：【Junit】Junit快速入门

一、项目框架

1、搭建一个Maven项目，引入 spring依赖、spring-test依赖 和 junit依赖

<?xml version="1.0" encoding="UTF-8"?>
<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>com.test.junit</groupId>
    <artifactId>test-junit-spring</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <!-- spring -->
        <spring.version>5.2.4.RELEASE</spring.version>
        <!-- Junit4 -->
        <junit.version>4.12</junit.version>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>

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

        <!-- Spring Test 模块 -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>${spring.version}</version>
            <scope>test</scope>
        </dependency>

        <!-- junit依赖 -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>${junit.version}</version>
        </dependency>
    </dependencies>

</project> 

2、准备一个Spring xml配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans https://www.springframework.org/schema/beans/spring-beans-4.0.xsd
                http://www.springframework.org/schema/aop https://www.springframework.org/schema/aop/spring-aop-4..xsd
                http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context-4.0.xsd
                http://www.springframework.org/schema/tx https://www.springframework.org/schema/tx/spring-tx-4.0.xsd">

    <bean id="date" class="java.util.Date"></bean>
</beans>

二、使用Junit4 测试 Spring

方法1：利用 @BeforeClass + xml文件 启动Spring容器

package com.test.junite.spring;

import org.junit.BeforeClass;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.util.Date;

/**
 * 利用 @BeforeClass 注解启动Spring容器，开始测试
 * @BeforeClass：它会在所有方法运行前被执行，static修饰
 */
public class SpringTest {

    private static ApplicationContext context = null;

    @BeforeClass
    public static void setUpBeforeClass() throws Exception {
        context = new ClassPathXmlApplicationContext("applicationContext.xml");
    }


    @Test
    public void test() {
        Date date = (Date) context.getBean("date");
        System.out.println(date);
    }
}

方法2：利用 @BeforeClass + 配置类 启动Spring容器

package com.test.junite.spring;

import org.junit.BeforeClass;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.util.Date;

/**
 * 利用 @BeforeClass 注解启动Spring容器，开始测试
 * @BeforeClass：它会在所有方法运行前被执行，static修饰
 */
public class SpringTest2 {

    private static ApplicationContext context = null;

    @BeforeClass
    public static void setUpBeforeClass() throws Exception {
        context = new AnnotationConfigApplicationContext(MyConfig.class);
    }


    @Test
    public void test() {
        Date date = (Date) context.getBean("date");
        System.out.println(date);
    }

    @Configuration
    static class MyConfig {
        @Bean
        public Date date(){
            return new Date();
        }
    }
}

方法3：利用 @RunWith运行器 + xml文件 启动Spring容器

/**
 * 利用 @RunWith 运行器，来运行一个Spring环境，@ContextConfiguration 导入相关配置
 *
 * @RunWith作用
 * @RunWith 就是一个运行器
 * @RunWith(JUnit4.class) 就是指用JUnit4来运行
 * @RunWith(SpringJUnit4ClassRunner.class),让测试运行于Spring测试环境
 * @RunWith(Suite.class) 的话就是一套测试集合，
 */
// junit整合spring的测试
// SpringRunner 继承了SpringJUnit4ClassRunner，
// 没有扩展任何功能；使用SpringRunner，名字简短而已
@RunWith(SpringRunner.class)
// @RunWith(SpringJUnit4ClassRunner.class)
// 加载核心xml配置文件，自动构建spring容器
@ContextConfiguration(locations="classpath:applicationContext.xml")
public class SpringTest3 {

    @Autowired
    private ApplicationContext contex;


    @Test
    public void test() {
        Date date = (Date) contex.getBean("date");
        System.out.println(date);
    }
}

方法4：利用 @RunWith运行器 + 配置类 启动Spring容器

package com.test.junite.spring;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.test.context.junit4.SpringRunner;

import java.util.Date;

// junit整合spring的测试
@RunWith(SpringRunner.class)
// 导入配置类，自动构建spring容器
@Import(SpringTest4.MyConfig.class)
public class SpringTest4 {

    @Autowired
    private ApplicationContext contex;

    @Test
    public void test() {
        Date date = (Date) contex.getBean("date");
        System.out.println(date);
    }

    @Configuration
    static class MyConfig{
        @Bean
        public Date date() {
            return new Date();
        }
    }
}