Junit测试maven+ssm项目的过程及出现的错误总结

旧城等待， 2022-06-10 10:00 187阅读 0赞

### junit进行单元测试通常有两种： ###

**1. 不使用spring封装的junit，手动加载**

package com.puhua.test;
    
    import org.junit.Before;
    import org.junit.Test;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    import org.springframework.test.context.junit4.AbstractJUnit4SpringContextTests;
    
    import com.puhua.model.Users;
    import com.puhua.service.UsersService;
    
    public class TestUsersMapper extends AbstractJUnit4SpringContextTests{ 
    
    
        private UsersService usersService;
    
        @SuppressWarnings("resource")
        @Before  
        public void before(){                                                                             
    
            ApplicationContext context = new ClassPathXmlApplicationContext(new String []{
       "classpath*/spring-mybatis.xml","classpath*:/spring-mvc.xml"});  
            System.out.println("_________________________");
            usersService = (UsersService) context.getBean("usersServiceImpl");
        }
    
        @Test  
        public void testSelectByPrimaryKey(){
            Long id = new Long(1);
            Users user = usersService.selectByPrimaryKey(id); 
            System.out.println(user);
        }  
    }

**2.通过spring封装的junit实现注解测试：**

package com.puhua.test;
    
    import javax.annotation.Resource;
    
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.springframework.test.context.ContextConfiguration;
    import org.springframework.test.context.junit4.AbstractJUnit4SpringContextTests;
    import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
    import org.springframework.test.context.web.WebAppConfiguration;
    
    import com.puhua.model.Users;
    import com.puhua.service.UsersService;
    
    @RunWith(SpringJUnit4ClassRunner.class)
    @ContextConfiguration(locations = { "classpath*:/spring-mybatis.xml","classpath*:/spring-mvc.xml"})
    @WebAppConfiguration
    public class SpringTest extends AbstractJUnit4SpringContextTests {
    
        @Resource
         private UsersService usersService;
    
         @Test
         public void testSelectByPrimaryKey(){
             Long id = new Long(1);
             Users user = usersService.selectByPrimaryKey(id);
             System.out.println(user.getUserName());
         }
    }

### 下面重点讲通过spring注解方式进行junit测试出现的问题及解决方法： ###

**1.基类上的三个注解一个都不能少：**

@RunWith(SpringJUnit4ClassRunner.class)
    @ContextConfiguration(locations = { "classpath*:/spring-mybatis.xml","classpath*:/spring-mvc.xml"})
    @WebAppConfiguration

其中@ContextConfiguration用来加载spring的配置文件，如果有多个，需要以逗号分开，也可以用通配符如：

@ContextConfiguration(locations = { "classpath*:/spring-*.xml"})

**但需要重点注意的是:classpath后面的\*号不能少，如果没有星号，会报如下错：**

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.puhua.test.SpringTest': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.puhua.service.UsersService com.puhua.test.SpringTest.usersService; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.puhua.service.UsersService] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
        at ...

**除此之外，@WebAppConfiguration的作用是：表明该类会使用web应用程序的默认根目录来载入ApplicationContext, 默认的更目录是”src/main/webapp”, 如果需要更改这个更目录可以修改该注释的value值。如果没加此注解，报错和上面一样**

**2.一切准备就绪，开始测试，发现又报错了，报错为**

Can't find bundle for base name javax.servlet.LocalStrings, locale zh_CN

**原因是缺少WEB服务运行的相关包，右键项目->build path->add Library->Server Runtime->选择你的tomcat，OK！**

再次测试，可以查到数据！