SpringBoot（五）Springmvc+Mybatis+mysql

为了整合这个花了，好长时间，因为上几个连在一起，在pom文件中有没注释的配置，导致我找这个问题找了好久。下面开始

1,先new project 时选择spring initializr，新建好一个空项目后，先在pom文件中配置springmvc+mybatis+mysql（有注解的是我新加的，没注解的是项目原有的）

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.oda</groupId>
    <artifactId>e-commerce</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>e-commerce</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.2.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <!-- 内嵌Tomcat使用 jsp 必要引入 -->
        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-jasper</artifactId>
        </dependency>

        <!--  Mybatis引入 -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.1</version>
        </dependency>

        <!--  Mysql引入 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

        <!--  jstl标签引入 -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

2.配置aplication.properties文件

server.port=8080
#SpringMvc配置视图
spring.mvc.view.prefix=/WEB-INF/views/
spring.mvc.view.suffix=.jsp
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test1?useUnicode=true&characterEncoding=utf-8&useSSL=false
spring.datasource.username=root
spring.datasource.password=root
mybatis.mapper-locations=classpath:sql/*.xml

3新建.UserController

package com.oda.controller;

import com.oda.service.UserService;
import org.apache.catalina.LifecycleState;
import org.apache.catalina.User;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;

import javax.annotation.Resource;
import java.util.List;

@Controller
public class UserController {

    @Resource
    private UserService userService;

    @RequestMapping("/welcome")
    public String index(Model model){
        List<User> users = userService.selectUsers();
        model.addAttribute("users",users);
        return "welcome";
    }
}

4.新建UserService

package com.oda.service;

import com.oda.dao.UserDao;
import org.apache.catalina.User;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.util.List;

@Service
public class UserService {

    @Resource
    private UserDao userDao;

    public List<User> selectUsers() {
        return userDao.selectUsers();
    }
}

5.新建UserDao

package com.oda.dao;

import org.apache.catalina.User;
import org.springframework.stereotype.Repository;

import java.util.List;

@Repository
public interface UserDao {
    List<User> selectUsers();
}

6.新建User

package com.oda.model;

import org.springframework.stereotype.Component;

@Component
public class User {
    private int id;
    private String name;
    private int age;

    public User() {
    }

    public User(int id, String name, int age) {
        this.id = id;
        this.name = name;
        this.age = age;
    }

    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;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}

7.新建use.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//ibatis.apache.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.oda.dao.UserDao">
    <select id="selectUsers" resultType="com.oda.model.User">
        select *
        from user
    </select>
</mapper>

8.新建welcome.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<head>
    <title></title>
</head>
<body>
<h1>This is a springmvc   ${message}</h1>
<table border="1px">
    <tr>
        <td>序号</td>
        <td>姓名</td>
        <td>年齡</td>
    </tr>
    <c:forEach items="${users}" var="u">
        <tr>
            <td>${u.id}</td>
            <td>${u.name}</td>
            <td>${u.age}</td>
        </tr>
    </c:forEach>
</table>
</body>
</html>

注意要改一下自己的Application类

package com.oda;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@MapperScan("com.oda.dao")
public class ECommerceApplication {

    public static void main(String[] args) {
        SpringApplication.run(ECommerceApplication.class, args);
    }
}

这就建好了，启动，访问http://localhost:8080/welcome

结果：

项目结构：