SSM整合（三）（插入和查询（重点查询））

添加spring-test模块

     <!-- spring-test -->
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-test -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>4.3.7.RELEASE</version>
        </dependency>

 测试mapper接口是否成功

package com.dotcore.test;

import com.dotcore.dao.DepartmentMapper;
import com.dotcore.dao.EmployeeMapper;
import com.dotcore.model.Department;
import com.dotcore.model.Employee;
import org.apache.ibatis.session.SqlSession;
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.support.ClassPathXmlApplicationContext;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import java.util.UUID;

/**
 * 测试dao层的工作
 *
 * @author xuerr
 * @version 2017/5/3
 *          推荐Spring的项目可以使用Spring的单元测试，可以自动注入我们需要的组件
 *          1、导入SpringTest模块
 *          2、@ContextConfiguration指定Spring配置的位置
 *          3、直接autowire要使用的组件
 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {"classpath:applicationContext.xml"})
public class MapperTest {

    @Autowired
    DepartmentMapper departmentMapper;
    @Autowired
    EmployeeMapper employeeMapper;
    @Autowired
    SqlSession sqlSession;

    /**
     * 测试DepartmetnMapper
     */
    @Test
    public void testCRUD() {
        //方法一：
        //1.创建SpringIOC容器
//        ApplicationContext ioc = new ClassPathXmlApplicationContext("applicationContext.xml");
        //2、从容器中获取mapper
//        DepartmentMapper bean = ioc.getBean(DepartmentMapper.class);

        //方法二：
//        System.out.println(departmentMapper);
        //1、插入几个部门
//        departmentMapper.insertSelective(new Department(null,"开发部"));
//        departmentMapper.insertSelective(new Department(null,"测试部"));

        //2、插入员工
//        employeeMapper.insertSelective(new Employee(null,"jack","M","11@qq.com",5));
        //这种批量插入速度就很慢了
//        for(int i = 0; i < 1000; i++){
//            employeeMapper.insertSelective();
//        }
        //批量插入
        EmployeeMapper mapper = sqlSession.getMapper(EmployeeMapper.class);
        for (int i = 0; i < 1000; i++) {
            String UID = UUID.randomUUID().toString().substring(0, 5) + i;
            mapper.insertSelective(new Employee(null, UID,"M",UID+"@qq.com",5));
        }


    }
}

批量插入的时候我们得配置

  <!--配置一个可以执行批量的sqlSession-->
    <bean class="org.mybatis.spring.SqlSessionTemplate" id="sqlSession">
        <constructor-arg name="sqlSessionFactory" ref="sqlSessionFactory"/>
        <constructor-arg name="executorType" value="BATCH"/>
    </bean>

=================================================================================================================================================

分页查询

1、引用一个分页插件PageHelper

https://github.com/pagehelper/Mybatis-PageHelper   看里面有个中文文档，引用完jar，点击 如何使用分页插件

首先你得添加jar包

<dependency>
    <groupId>com.github.pagehelper</groupId>
    <artifactId>pagehelper</artifactId>
    <version>5.0.1</version>
</dependency>

1. 在 MyBatis 配置 xml 中配置拦截器插件

<!-- 
    plugins在配置文件中的位置必须符合要求，否则会报错，顺序如下:
    properties?, settings?, 
    typeAliases?, typeHandlers?, 
    objectFactory?,objectWrapperFactory?, 
    plugins?, 
    environments?, databaseIdProvider?, mappers?
-->
<plugins>
    <!-- com.github.pagehelper为PageHelper类所在包名 -->
    <plugin interceptor="com.github.pagehelper.PageInterceptor">
        <!-- 使用下面的方式配置参数，后面会有所有的参数介绍 -->
        <!--<property name="param1" value="value1"/> -->
  <!-- 设置数据库类型 Oracle,Mysql,MariaDB,SQLite,Hsqldb,PostgreSQL六种数据库-->
            <property name="dialect" value="mysql"/>
    </plugin>
</plugins>

在控制器中对分页插件的使用

package com.dotcore.controller;

import com.dotcore.model.Employee;
import com.dotcore.service.EmployeeService;
import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

import java.util.List;

/**
 * @author xuerr
 * @version 2017/5/4
 */
@Controller
public class EmployeeController {
    @Autowired
    EmployeeService employeeService;
    /**
     * 查询员工数据（分页查询）
     * @return
     */
//    @RequestMapping("/emps")
//    public String getEmps(){
//        //这不是一个分页查询
//        List<Employee> emps = employeeService.getAll();
//        return "list";
//    }
    @RequestMapping("/emps")
    public String getEmps(@RequestParam(value="pn",defaultValue="1")Integer pn, Model model){
        //引入PageHelper分页插件
        //在查询之前只需要调用，传入页码，以及每页大小
        PageHelper.startPage(pn,5);
        List<Employee> emps = employeeService.getAll();
        //使用PageInfo包装查询的数据,只需要把PageInfo交给页面就好了
        //封装详细的分页信息，包括我们查询出来的数据
        PageInfo pageInfo = new PageInfo(emps,5);
        model.addAttribute("pageInfo",pageInfo);
        return "list";
    }
}

现在来个单元测试，测试成功后，就开始写页面

=================================================================================================================================================

单元测试（记住mysql的服务要开，我前面忘记了）

package com.dotcore.test;

import com.dotcore.model.Employee;
import com.github.pagehelper.PageInfo;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.mock.web.MockHttpServletRequest;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.web.WebAppConfiguration;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.MvcResult;
import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import org.springframework.web.context.WebApplicationContext;

import java.util.List;

/**
 * @author xuerr
 * @version 2017/5/4
 * 这里spring的配置文件是不够的，这里还要加一个springmvc的配置文件file。。。。
 *使用Spring测试模块提供的测试请求功能，测试crud请求的正确性
 * Spring4测试的时候，需要servlet3.0的支持
 *
 */
//servlet版本不够，所以我们换高点上去
//        <dependency>
//        <groupId>javax.servlet</groupId>
//        <artifactId>servlet-api</artifactId>
//        <!--服务器里有，发布到服务器上不需要这个包 -->
//        <scope>provided</scope>
//        <version>2.5</version>
//        </dependency>

@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration
@ContextConfiguration(locations = {"classpath:applicationContext.xml","file:src/main/webapp/WEB-INF/dispatcherServlet-servlet.xml"})
public class MvcTest {
    //虚拟MVC请求，获取到处理结果
    MockMvc mockMvc;
    //@WebAppConfiguration这个引用后，才能拿到context
    @Autowired
    WebApplicationContext context;

    //用junit的before
    @Before
    public void initMokcMvc(){
        mockMvc = MockMvcBuilders.webAppContextSetup(context).build();
    }
    @Test
    public void testPage() throws Exception {
        //模拟请求，拿到返回值
        MvcResult result = mockMvc.perform(MockMvcRequestBuilders.get("/emps").param("pn", "1"))
                .andReturn();

        //请求成功以后，请求域中会与pageInfo，我们可以取出pageInfo进行验证
        MockHttpServletRequest request = result.getRequest();
        PageInfo pi = (PageInfo) request.getAttribute("pageInfo");
        System.out.println("当前页码"+pi.getPageNum());
        System.out.println("总页码"+pi.getPages());
        System.out.println("总记录数"+pi.getTotal());
        System.out.println("在页面需要连续显示的页码");
        int[] nums = pi.getNavigatepageNums();
        for(int i:nums){
            System.out.println(" "+i);
        }
        //获取员工数据
        List<Employee> list = pi.getList();
        for(Employee employee:list){
            System.out.println("ID:"+employee.getEmpId()+"NAME:"+employee.getEmpName());
        }
    }
}