Spring Boot整合H2测试DAO

旧城等待， 2022-07-11 08:25 199阅读 0赞

在写DAO层的单元测试时，我们往往会遇到一个问题，测试用例所依赖的数据库数据被修改或删除了，或者在一个新的环境下所依赖的数据库不存在，导致单元测试无法通过，进而构建失败。  
在这种情况下，使用H2内存数据库来模拟数据库环境是一个很好的解决方案

H2是一个短小精干的嵌入式数据库引擎，主要的特性包括：

1: 免费、开源、快速  
2: 嵌入式的数据库服务器，支持集群  
3: 提供JDBC、ODBC访问接口，提供基于浏览器的控制台管理程序  
4: Java编写，可使用GCJ和IKVM.NET编译

5: 短小精干的软件，1M左右。

官方网站为：http://www.h2database.com/html/main.html

本文章来演示一个Spring Boot + Mybatis + H2的单元测试例子

先新建一个maven项目 spring-boot-test-h2

项目结构如下：

![Center][]

其中，Mapper是操作数据库的，也就是DAO层。

具体代码如下：

pom.xml

<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.pp</groupId>
    	<artifactId>spring-boot-test-h2</artifactId>
    	<version>1.0.0</version>
    	<packaging>jar</packaging>
    
    	<name>spring-boot-test-h2</name>
    	<url>http://maven.apache.org</url>
    
    	<parent>
    		<groupId>org.springframework.boot</groupId>
    		<artifactId>spring-boot-starter-parent</artifactId>
    		<version>1.4.3.RELEASE</version>
    	</parent>
    
    	<properties>
    		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    		<maven.compiler.source>1.8</maven.compiler.source>
    		<maven.compiler.target>1.8</maven.compiler.target>
    	</properties>
    
    	<dependencies>
    		<dependency>
    			<groupId>mysql</groupId>
    			<artifactId>mysql-connector-java</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-jdbc</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>org.mybatis.spring.boot</groupId>
    			<artifactId>mybatis-spring-boot-starter</artifactId>
    			<version>1.2.0</version>
    		</dependency>
    		
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-test</artifactId>
    			<scope>test</scope>
    		</dependency>
    		<dependency>
    			<groupId>com.h2database</groupId>
    			<artifactId>h2</artifactId>
    			<scope>test</scope>
    		</dependency>
    	</dependencies>
    </project>

package com.pp.test;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    /**
     *  启动入口
     */
    @SpringBootApplication
    public class App {
    	public static void main( String[] args ) {
    		SpringApplication.run(App.class, args);
        }
    }

package com.pp.test.config;
    
    import org.mybatis.spring.annotation.MapperScan;
    import org.springframework.context.annotation.Configuration;
    
    /**
     * 配置Mapper的扫描包路径 
     */
    @Configuration
    @MapperScan("com.pp.test.mapper")
    public class MybatisScanConfiguration {
    
    }

package com.pp.test.entity;
    
    public class User {
    
    	private Integer id;
    	private String username;
    	private String password;
    	private Integer status;
    	
    	public User(){}
    	public User(String username, String password, Integer status) {
    		this.username = username;
    		this.password = password;
    		this.status = status;
    	}
    	public Integer getId() {
    		return id;
    	}
    	public void setId(Integer id) {
    		this.id = id;
    	}
    	public String getUsername() {
    		return username;
    	}
    	public void setUsername(String username) {
    		this.username = username;
    	}
    	public String getPassword() {
    		return password;
    	}
    	public void setPassword(String password) {
    		this.password = password;
    	}
    	public Integer getStatus() {
    		return status;
    	}
    	public void setStatus(Integer status) {
    		this.status = status;
    	}
    	@Override
    	public String toString() {
    		return "User [id=" + id + ", username=" + username + ", password=" + password + ", status=" + status + "]";
    	}
    }

package com.pp.test.mapper;
    
    import java.util.List;
    
    import org.apache.ibatis.annotations.Delete;
    import org.apache.ibatis.annotations.Insert;
    import org.apache.ibatis.annotations.Options;
    import org.apache.ibatis.annotations.Select;
    import org.apache.ibatis.annotations.Update;
    
    import com.pp.test.entity.User;
    
    public interface UserMapper {
    
    	@Options(useGeneratedKeys = true, keyProperty = "id") //回写自增的主键ID
    	@Insert("insert into users (username,password,status)values(#{username},#{password},#{status})")
    	public Integer addUser(User user);
    	
    	@Delete("delete from users where id=#{0}")
    	public Integer deleteUserById(Integer id);
    	
    	@Update("update users set username=#{username},password=#{password},status=#{status} where id=#{id}")
    	public Integer updateUser(User user);
    	
    	@Select("select * from users where id=#{0}")
    	public User getById(Integer id);
    	
    	@Select("select * from users")
    	public List<User> queryUserList();
    }

单元测试类：

package com.pp.test.mapper;
    
    import java.util.List;
    
    import org.junit.Assert;
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.mybatis.spring.boot.autoconfigure.MybatisAutoConfiguration;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
    import org.springframework.boot.test.context.SpringBootTest;
    import org.springframework.test.context.junit4.SpringRunner;
    
    import com.pp.test.config.MybatisScanConfiguration;
    import com.pp.test.entity.User;
    
    @RunWith(SpringRunner.class)
    /**
     *  这里指定的classes是可选的。如果不指定classes，则spring boot会启动整个spring容器，很慢（比如说会执行一些初始化，ApplicationRunner、CommandLineRunner等等）。不推荐
     *  指定的话，就只会初始化指定的bean，速度快，推荐
     */
    @SpringBootTest(classes={DataSourceAutoConfiguration.class, MybatisAutoConfiguration.class, MybatisScanConfiguration.class})
    public class UserMapperTest {
    	
    	@Autowired
    	private UserMapper userMapper;
    
    	@Test
    	public void testAddUser() {
    		User user = new User("admin","123",1);
    		userMapper.addUser(user);
    		Assert.assertNotNull(user.getId());
    	}
    
    	@Test
    	public void testDeleteUserById() {
    		User user = new User("admin","123",1);
    		userMapper.addUser(user);
    		Integer count = userMapper.deleteUserById(user.getId());
    		Assert.assertEquals(new Integer(1), count);
    	}
    
    	@Test
    	public void testUpdateUser() {
    		User user = new User("admin","123",1);
    		userMapper.addUser(user);
    		user.setUsername("hr");
    		userMapper.updateUser(user);
    		Assert.assertEquals("hr", user.getUsername());
    	}
    
    	@Test
    	public void testGetById() {
    		User user = new User("admin","123",1);
    		userMapper.addUser(user);
    		
    		User obj = userMapper.getById(user.getId());
    		Assert.assertEquals("admin", obj.getUsername());
    		Assert.assertEquals("123", obj.getPassword());
    		Assert.assertEquals(new Integer(1), obj.getStatus());
    	}
    
    	@Test
    	public void testQueryUserList() {
    		User user = new User("admin","123",1);
    		userMapper.addUser(user);
    		List<User> users = userMapper.queryUserList();
    		Assert.assertTrue(!users.isEmpty());
    	}
    }

init\_table.sql

create table if not exists users (id int not null primary key auto_increment,username varchar(100),password varchar(100),status int);

application.properties(src/test/resources)

spring.datasource.driverClassName=org.h2.Driver
    spring.datasource.url=jdbc:h2:mem:db_users;MODE=MYSQL;INIT=RUNSCRIPT FROM './src/test/resources/init_table.sql'
    spring.datasource.username=
    spring.datasource.password=

注意

1：这里面的INIT=RUNSCRIPT，这里用来初始化init\_table.sql脚本的

2：maven在跑单元测试的时候，优先读取src/test/resources的配置文件，没有则读取src/main/resources下的配置文件。所以，这里的h2的数据库驱动配置务必配置在

src/test/resources/application.properties文件中。真正的数据库配置要配置在src/main/resources/application.properties文件中

最后，执行 mvn clean test 就可以跑单元测试了。

[Center]: /images/20220711/02ec9a2793a84aa88f48e9bf726ed564.png