IDEA spring mvc整合mybatis

准备工作

IDEA 2019.3.1

MySql 8.0.17

Tomcat 7.0.9

开始步骤

一、创建一个项目，添加Web支持

点击菜单:File->NEW->Project

选择左侧的Maven项目，这里的 Create from archetype先不要选择，然后点击Next

项目建好之后，目录结构如下：

在项目上右键单击，弹出菜单,选择 Add Framework Support

弹出如下界面，勾选左侧的Web Application(4.0),点击OK

点击OK之后，可以看到项目的目录结构有web文件夹了

二、项目搭建

1.数据库

新建数据库，创建一个student表,并插入几条数据

create table test.student
(
    id integer auto_increment primary key ,
    name varchar(50),
    age int,
    detail varchar(200)
)

insert into test.student(name,age,detail) values
('Tony1',18,'Tony1 is handsome');
insert into test.student(name,age,detail) values
('Tony2',19,'Tony2 is more handsome');
insert into test.student(name,age,detail) values
('Tony2',20,'Tony3 is most handsome');

2.项目目录

在项目结构的/src/main/java文件夹下创建一个包，并添加dao,service,entities,controller这四个文件夹，在/web/WEB-INF目录下添加jsp文件夹：

3.配置文件

本项目总共有7个配置文件：

web.xml:项目的配置文件

applicationContext.xml：spring总的配置文件，会引用controller/service/dao的配置文件

spring-controller.xml：controller层的配置文件

spring-service.xml：service层的配置文件

spring-dao.xml：dao层的配置文件，同时配置，mybatis的配置扫描

db.properties：数据库配置文件，被dao引用

StudentDao.xml：mybatis实体类映射文件

4.maven配置

引入springmvc ,mybatis所需的包，配置如下：

<dependencies>
        <!--Junit-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <!--数据库驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <!-- 数据库连接池 -->
        <dependency>
            <groupId>com.mchange</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.5.2</version>
        </dependency>

        <!--Servlet - JSP -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.2</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>

        <!--Mybatis-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.2</version>
        </dependency>

        <!--Spring-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.1.9.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.1.9.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.1.9.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.10</version>
        </dependency>

    </dependencies>

解决资源文件的依赖问题：

<build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
        </resources>
    </build>

三、代码编写

1.在entities包中添加Student类：

package com.Tony.entities;

public class Student {
    private int id;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getDetail() {
        return detail;
    }

    public void setDetail(String detail) {
        this.detail = detail;
    }

    private String name;
    private int age;
    private String detail;
}

2.在dao包中添加StudentDao接口：

package com.Tony.dao;

import com.Tony.entities.Student;

import java.util.List;

public interface StudentDao {
    Student findStudentById(int id);
    List<Student> findAllStudent();

    int deleteStudent(int id);

    int updateStudent(Student student);

    int addStudent(Student student);
}

3.在dao中添加StudentDao.xml 映射文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.Tony.dao.StudentDao">
    <select id="findStudentById" parameterType="int" resultType="com.Tony.entities.Student">
        select * from test.student where id=#{id}
    </select>

    <select id="findAllStudent" resultType="com.Tony.entities.Student">
        select * from test.student
    </select>

    <delete id="deleteStudent" parameterType="int">
        delete from test.student where id=#{id}
    </delete>

    <update id="updateStudent" parameterType="com.Tony.entities.Student">
        update test.student set name=#{name},age=#{age},detail=#{detail} where id=#{id}
    </update>

    <insert id="addStudent" parameterType="com.Tony.entities.Student">
        insert into test.student(name,age,detail) values
        (#{name},#{age},#{detail})
    </insert>
</mapper>

4.在service包中添加StudentService接口和其实现类StudentServiceImpl:

StudentService:

package com.Tony.service;

import com.Tony.entities.Student;

import java.util.List;

public interface StudentService {
    Student findStudentById(int id);
    List<Student> findAllStudent();

    int deleteStudent(int id);

    int updateStudent(Student student);

    int addStudent(Student student);
}

StudentServiceImpl:

package com.Tony.service;

import com.Tony.dao.StudentDao;
import com.Tony.entities.Student;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class StudentServiceImpl implements StudentService {

    @Autowired
    private StudentDao studentDao;

    public Student findStudentById(int id) {
        return this.studentDao.findStudentById(id);
    }

    public List<Student> findAllStudent() {
        return this.studentDao.findAllStudent();
    }

    public int deleteStudent(int id) {
        return this.studentDao.deleteStudent(id);
    }

    public int updateStudent(Student student) {
        return this.studentDao.updateStudent(student);
    }

    public int addStudent(Student student) {
        return this.studentDao.addStudent(student);
    }
}

5.在controller包中添加StudentController,并添加showAllStudent接口：

package com.Tony.controller;

import com.Tony.entities.Student;
import com.Tony.service.StudentService;
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 java.util.List;

@Controller
@RequestMapping("/student")
public class StudentController {

    @Autowired
    private StudentService studentService;

    @RequestMapping("/showAllStudent")
    public String showAllStudent(Model model)
    {
        List<Student> list=studentService.findAllStudent();
        model.addAttribute("list",list);
        return "allStudent";
    }
}

6.在/web/WEB-INF/jsp/文件夹中添加allStudent.jsp页面：

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>显示所有的学生</title>
</head>
<body>
    <table>
        <thead>
        <tr>
            <td>学生ID</td>
            <td>学生姓名</td>
            <td>学生年龄</td>
            <td>学生明细</td>
        </tr>
        </thead>
        <tbody>
        <c:forEach var="student" items="${requestScope.get('list')}">
            <tr>
                <td>${student.id}</td>
                <td>${student.name}</td>
                <td>${student.age}</td>
                <td>${student.detail}</td>
            </tr>
        </c:forEach>
        </tbody>
    </table>
</body>
</html>

四、配置文件

1.db.properties

jdbc.url=jdbc:mysql://localhost:3306/test
jdbc.username=root
jdbc.password=123456
jdbc.driver=com.mysql.jdbc.Driver

2.spring-dao.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
        https://www.springframework.org/schema/context/spring-context.xsd">

    <context:property-placeholder location="classpath:db.properties"></context:property-placeholder>

    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${jdbc.driver}"></property>
        <property name="user" value="${jdbc.username}"></property>
        <property name="password" value="${jdbc.password}"></property>
        <property name="jdbcUrl" value="${jdbc.url}"></property>
    </bean>

    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>
        <property name="basePackage" value="com.Tony.dao"></property>
    </bean>
</beans>

3.spring-service.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"
       xmlns:cache="http://www.springframework.org/schema/cache"
       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
        http://www.springframework.org/schema/cache
        http://www.springframework.org/schema/cache/spring-cache.xsd">
        <context:component-scan base-package="com.Tony.service"></context:component-scan>
</beans>

4.spring-controller.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"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       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
    http://www.springframework.org/schema/mvc
    https://www.springframework.org/schema/mvc/spring-mvc.xsd">
    <!--扫描@controller注解-->
    <context:component-scan base-package="com.Tony.controller"></context:component-scan>

    <!--@RequestMapping生效-->
    <mvc:annotation-driven></mvc:annotation-driven>

    <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/jsp/"></property>
        <property name="suffix" value=".jsp"></property>
    </bean>

</beans>

5.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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd">
    <import resource="classpath:spring-controller.xml"></import>
    <import resource="classpath:spring-dao.xml"></import>
    <import resource="classpath:spring-service.xml"></import>
</beans>

6.web.xml

<?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">
    <servlet>
        <servlet-name>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:applicationContext.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

最后，整个项目的目录结构如下：

五、配置Tomcat

点击上方的AddConfiguration按钮

弹出如下界面，点击+号，选择Tomcat Server->Local

弹出如下界面，点击fix:

配置后，这里就看得到刚配置的Tomcat服务器名了：

六、配置打包的Artifacts:

点击菜单File->Project Structure:

弹出如下界面，选择左侧的Artifacts:

在Output Layout的WEB-INF下新建一个lib文件夹(注意此处必须是lib，全部是小写，写错了会导致出各种错误)：

选中lib文件夹，右键单击，弹出菜单，选择Add Copy of->Library Files:

七、运行项目：

点击如下的播放按钮运行项目，运行起来之后，IDEA会自动打开浏览器

打开浏览器之后，默认是如下的网址：

我们需要加上显示所有学生的网址，然后按回车键，就可以显示所有的学生了：

八、各种问题排查

1.不支持发行版本5:

解决办法：

点击菜单：File->Setting,弹出如下界面，选择左边的Build,Execution,Deployment->Compiler->Java Compiler,

将项目的target bytecode version从1.5改为9