SpringBoot重点详解--使用Junit进行单元测试

目录

添加依赖与配置

ApplicationContext测试

Environment测试

MockBean测试

Controller测试

情况一

情况二

方法一

方法二

---

本文将对在Springboot中如何使用Junit进行单元测试进行简单示例和介绍，项目的完整目录层次如下图所示。 

添加依赖与配置

为了保证测试的完整性，本工程POM文件中除引入Junit单元测试依赖外，还额外引入了用来测试JDBC和Controller的JPA和WEB依赖。 

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.5.6.RELEASE</version>
	</parent>
 
	<dependencies>
		<!-- 添加MySQL依赖 -->
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
		</dependency>
		<!-- 添加JDBC依赖 -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-jpa</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<!-- 引入单元测试依赖 -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

同时，在src/main/resources目录下添加核心配置文件application.properties，内容如下。  

#########################################################
###  Spring DataSource  -- DataSource configuration   ###
#########################################################
spring.datasource.url=jdbc:mysql://localhost:3306/dev1?useUnicode=true&characterEncoding=utf8
spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.username=root
spring.datasource.password=123456
 
#########################################################
### Java Persistence Api --  Spring jpa configuration ###
#########################################################
# Specify the DBMS
spring.jpa.database = MYSQL
# Show or not log for each sql query
spring.jpa.show-sql = true
# Hibernate ddl auto (create, create-drop, update)
spring.jpa.hibernate.ddl-auto = update
# Naming strategy
#[org.hibernate.cfg.ImprovedNamingStrategy  #org.hibernate.cfg.DefaultNamingStrategy]
spring.jpa.hibernate.naming-strategy = org.hibernate.cfg.ImprovedNamingStrategy
# stripped before adding them to the entity manager)
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect

ApplicationContext测试

在Springboot中使用Junit进行单元测试的方法很简单，只需要在编写的单元测试类上添加两个注解：@RunWith(SpringRunner.class)和@SpringBootTest。 

@RunWith(SpringRunner.class) // 等价于使用 @RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest(classes = { MyApplication.class, TestConfig.class })
public class ApplicationContextTest {
 
	@Autowired
	private ApplicationContext context;
 
	@Autowired
	private UserDao userDao;
 
	@Test
	public void testUserDao() {
		userDao.addUser(18, "pengjunlee");
	}
 
	@Test
	public void testConfiguration() {
		Runnable bean = context.getBean(Runnable.class);
		Assert.assertNotNull(bean);
		bean.run();
	}
 
}

UserDao定义如下。  

@Repository
public class UserDao {
 
	@Autowired
	private JdbcTemplate jdbcTemplate;
 
	@Transactional
	public void addUser(Integer userAge, String userName) {
		String sql = "insert into tbl_user (age,name) values ('" + userAge + "','" + userName + "');";
		jdbcTemplate.execute(sql);
	}
}

TestConfig定义如下。 

/**
 * @TestConfiguration注解的配置内的Bean仅在测试时装配
 */
@TestConfiguration
public class TestConfig {
 
	@Bean
	public Runnable createRunnable(){
		return ()->{
			System.out.println("This is a test Runnable bean...");
		};
	}
}

提示：@SpringBootTest注解的classes可以指定用来加载Spring容器所使用的配置类，@TestConfiguration注解修饰的配置类内的Bean仅在测试的时候才会装配。  

Environment测试

我们可以通过@SpringBootTest注解的properties属性向Environment中设置新的属性，也可以通过使用EnvironmentTestUtils工具类来向ConfigurableEnvironment中添加新的属性。 

@RunWith(SpringRunner.class)
@SpringBootTest(properties = { "app.token=pengjunlee" })
public class EnvironmentTest {
 
	@Autowired
	private Environment env;
 
	@Autowired
	private ConfigurableEnvironment cenv;
 
	@Before
	public void init() {
		EnvironmentTestUtils.addEnvironment(cenv, "app.secret=55a4b77eda");
	}
 
	@Test
	public void testEnvironment() {
		System.out.println(env.getProperty("spring.datasource.url"));
		Assert.assertEquals("pengjunlee", env.getProperty("app.token"));
		Assert.assertEquals("55a4b77eda", cenv.getProperty("app.secret"));
	}
 
	@Test
	@Ignore // 忽略测试方法
	public void testIgnore() {
 
		System.out.println("你看不见我...");
	}
 
}

扩展：Junit测试用例执行顺序：@BeforeClass ==> @Before ==> @Test ==> @After ==> @AfterClass 。

注意：在使用Junit对Spring容器进行单元测试时，若在src/test/resources 目录下存在核心配置文件，Spring容器将会只加载src/test/resources 目录下的核心配置文件，而不再加载src/main/resources 目录下的核心配置文件。  

MockBean测试

我们可以通过@MockBean注解来对那些未添加实现的接口进行模拟测试，预先设定好调用方法期待的返回值，然后再进行测试。

例如，有如下的IUserService接口，定义了一个getUserAge()方法用来根据用户的ID来查询用户的年龄。 

public interface IUserService {
 
	Integer getUserAge(Long userId);
 
}

使用@MockBean来对IUserService接口进行模拟测试，测试代码如下。  

@RunWith(SpringRunner.class)
public class MockBeanTest {
 
	@MockBean
	private IUserService userService;
 
	@SuppressWarnings("unchecked")
	@Test(expected = NullPointerException.class)
	public void testMockBean() {
 
		BDDMockito.given(userService.getUserAge(2L)).willReturn(Integer.valueOf(18));
		BDDMockito.given(userService.getUserAge(0L)).willReturn(Integer.valueOf(0));
		BDDMockito.given(userService.getUserAge(null)).willThrow(NullPointerException.class);
 
		Assert.assertEquals(Integer.valueOf(18), userService.getUserAge(2L));
		Assert.assertEquals(Integer.valueOf(0), userService.getUserAge(0L));
		Assert.assertEquals(Integer.valueOf(0), userService.getUserAge(null));
 
	}
}

Controller测试

在Springboot中可以通过TestRestTemplate和MockMvc来对Controller进行测试，有以下两种情况。

情况一

Controller中未装配任何其他Spring容器中的Bean，例如下面这个控制器。 

@RestController
@RequestMapping("/user")
public class UserController01 {
 
	@GetMapping("/home")
	public String homeUser(@RequestParam(name = "name", required = true) String userName) {
		if (null == userName || userName.trim() == "") {
			return "you are nobody...";
		}
		return "This is " + userName + "'s home...";
	}
}

此时无需启动Spring容器，可直接使用MockMvc来对Controller进行模拟测试，测试代码如下。  

@RunWith(SpringRunner.class)
@WebMvcTest(controllers = { UserController01.class })
public class ControllerTest01 {
 
	@Autowired
	private MockMvc mvc;
 
	@Test
	public void testAddUser() throws Exception {
		mvc.perform(MockMvcRequestBuilders.get("/user/home").param("name", ""))
				.andExpect(MockMvcResultMatchers.status().isOk())
				.andExpect(MockMvcResultMatchers.content().string("you are nobody..."));
		mvc.perform(MockMvcRequestBuilders.get("/user/home").param("name", "pengjunlee"))
				.andExpect(MockMvcResultMatchers.status().isOk())
				.andExpect(MockMvcResultMatchers.content().string("This is pengjunlee's home..."));
	}
 
}

情况二

Controller中需装配其他Spring容器中的Bean，例如下面这个控制器。 

@RestController
@RequestMapping("/user")
public class UserController02 {
 
	@Autowired
	private UserDao userDao;
 
	@GetMapping("/add")
	public String addUser(@RequestParam(name = "age", required = false, defaultValue = "0") Integer userAge,
			@RequestParam(name = "name", required = true) String userName) {
		if (userAge <= 0 || null == userName || userName.trim() == "") {
			return "0";
		}
		userDao.addUser(userAge, userName);
		return "1";
	}
 
}

此时除了要启动Spring容器，还需要启动内嵌的WEB环境，有以下两种方法。

方法一

利用TestRestTemplate进行测试。 

@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
public class ControllerTest02 {
 
	@Autowired
	private TestRestTemplate template;
 
	@Test
	public void testAddUser() {
		String result1 = template.getForObject("/user/add?name=pengjunlee", String.class);
		Assert.assertEquals("0", result1);
		String result2 = template.getForObject("/user/add?age=20&name=Tracy", String.class);
		Assert.assertEquals("1", result2);
	}
 
}

方法二

利用MockMvc进行测试。 

@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
@AutoConfigureMockMvc
public class ControllerTest03 {
 
	@Autowired
	private MockMvc mvc;
 
	@Test
	public void testAddUser() throws Exception {
		mvc.perform(MockMvcRequestBuilders.get("/user/add").param("name", ""))
				.andExpect(MockMvcResultMatchers.status().isOk())
				.andExpect(MockMvcResultMatchers.content().string("0"));
		mvc.perform(MockMvcRequestBuilders.get("/user/add").param("age", "22").param("name", "pengjunlee"))
				.andExpect(MockMvcResultMatchers.status().isOk())
				.andExpect(MockMvcResultMatchers.content().string("1"));
	}
 
}

本文项目源码已上传至CSDN，资源地址：https://download.csdn.net/download/pengjunlee/10394302  

原文地址：https://blog.csdn.net/pengjunlee/article/details/80206615