Spring整合Junit、Servlet

• 整合Junit
• • 使用的jar包
  • 创建项目
• 整合Servlet
• • 使用的jar包
  • 创建项目
  • 在 Web 项目中启动 Spring 框架
  • 在 Servlet 中获取 Bean 对象

整合Junit

使用的jar包

创建项目

创建配置文件 applicationContext.xml

<?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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
  http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">

    <context:component-scan base-package="com.bjsxt"/>
</beans>

创建业务层代码

package com.bjsxt.service;

public interface UsersService {
    void addUsers();
}

import com.bjsxt.service.UsersService;
import org.springframework.stereotype.Service;

@Service	
//配置注解，使得配置文件可以扫描到
public class UsersServiceImpl implements UsersService {
    @Override
    public void addUsers() {
        System.out.println("AddUsers.....");
    }
}

创建测试类

import com.bjsxt.service.UsersService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

//1. 更换测试引擎
@RunWith(SpringJUnit4ClassRunner.class)

//2. 指定Spring配置文件
@ContextConfiguration(locations = {"classpath:applicationContext.xml"})
public class UsersServiceImplTest {
//3. 使用依赖注入，在测试类内注入要测试的对象
    @Autowired
    private UsersService usersService;
//4. 在测试方法内完成对测试方法的测试
    @Test
    public void testAddUsers(){
            this.usersService.addUsers();
    }
}

整合Servlet

使用的jar包

创建项目

如果是web工程的话，我们还需要将添加的jar包都导入到项目的lib下

创建配置文件 applicationContext.xml

<?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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
 
</beans>

在 Web 项目中启动 Spring 框架

在 Web 项目中需要在 web.xml 文件中配置启动 Spring 框架的监听器。用于启动 Spring 框架。

修改 web.xml 文件

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">
    <!--指定配置文件的位置-->
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:applicationContext.xml</param-value>
    </context-param>
    <!--配置启动Spring框架的监听器-->
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
</web-app>

在 Servlet 中获取 Bean 对象

创建业务层

package com.bjsxt.service;

public interface UsersService {
    void addUsers();
}

package com.bjsxt.service.impl;
 
import com.bjsxt.service.UsersService; 
import org.springframework.stereotype.Service;

@Service
public class UsersServiceImpl implements UsersService { 
    @Override
    public void addUsers() {
        System.out.println("AddUsers......");
    }
}

创建 Servlet

package com.bjsxt.web.servlet;

import com.bjsxt.service.UsersService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebServlet(urlPatterns = "/addUsers.do")
public class UsersServlet extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        this.doPost(req, resp);
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //如何在servlet内获取springIOC容器中的bean对象
         //方式一 通过ServletContext对象获取WebApplicationContext，之后通过它的getBean方法获取bean对象
/*        WebApplicationContext webApplicationContext = (WebApplicationContext)this.getServletContext().getAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE);
        UsersService usersService = (UsersService)webApplicationContext.getBean("usersServiceImpl");
        resp.getWriter().print("hello welcome");
        usersService.addUsers();*/

        //方式二 通过工具类获取WebApplicationContext对象
        WebApplicationContext webApplicationContext = WebApplicationContextUtils.getWebApplicationContext(this.getServletContext());
        UsersService usersService = (UsersService)webApplicationContext.getBean("usersServiceImpl");
        resp.getWriter().print("hello welcome");
        usersService.addUsers();
    }
}

配置文件 applicationContext.xml的注解扫描

<?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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
    <context:component-scan base-package="com.bjsxt.service"/>
</beans>

运行结果：


创建持久层

package com.bjsxt.dao;

public interface UsersDao {
    void insertUsers();
}

package com.bjsxt.dao.impl;

import com.bjsxt.dao.UsersDao;
import org.springframework.stereotype.Repository; 

@Repository
//使用@Repository 将持久层注入到业务层内
public class UsersDaoImpl implements UsersDao {
    @Override
    public void insertUsers() {
        System.out.println("insert into users....");
    }
}

在业务层的UsersServiceImpl类的方法内添加和持久层有关的成员变量
并使用@Autowired完成对于对象的注入

package com.bjsxt.service.impl;

import com.bjsxt.dao.UsersDao;
import com.bjsxt.service.UsersService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class UsersServiceImpl implements UsersService {
    @Autowired
    private UsersDao usersDao;
    @Override
    public void addUsers() {
        System.out.println("AddUsers......");
        this.usersDao.insertUsers();
    }
}

修改 Spring 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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
    <context:component-scan base-package="com.bjsxt.service,com.bjsxt.dao"/>
</beans>

再次运行，运行的结果为：