SpringBoot實(shí)戰(zhàn)

Spring boot + Mybatis 整合

Spring boot+Mybatis，相對于原來的Spring+SpringMVC+Mybatis簡單好多

一、java web開發(fā)環(huán)境搭建

參考教程：http://www.itdecent.cn/p/39dec5a0ab55

二、Spring boot搭建

1、Intellij idea菜單欄File->new->project

創(chuàng)建新項(xiàng)目

2、選擇左側(cè)欄中spring initializr，右側(cè)選擇jdk版本，以及默認(rèn)的Service URL，點(diǎn)擊next。

選擇JDK和默認(rèn)URL

3、然后填寫項(xiàng)目的Group、Artifact等信息，helloworld階段選默認(rèn)就可以了，點(diǎn)擊next。

自定義包名

4、左側(cè)點(diǎn)擊Web選擇web，SQL選擇Mybatis、MYSQL（數(shù)據(jù)庫用的是mysql，大家可以選擇其他DB），點(diǎn)擊next。

選擇組件

5、填寫Project name 等信息，然后點(diǎn)擊Finish。

選擇項(xiàng)目名稱和地址

6、一個(gè)maven web項(xiàng)目就創(chuàng)建好了，目錄結(jié)構(gòu)如下：

項(xiàng)目創(chuàng)建完成

Spring boot就搭建好了，pom.xml里已經(jīng)有了Spring boot的jar包，包括我們的mysql數(shù)據(jù)連接的jar包。Spring boot內(nèi)置了類似tomcat這樣的中間件，所以，只要運(yùn)行DemoApplication中的main方法就可以啟動(dòng)項(xiàng)目了。

在src/main/java下新建目錄com/demo/entity/User

package com.example.demo.entity;

public class User {
    private  String name;

    public String getName() {
        return name;
    }

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

相同demo目錄下新建controller/TestBootController

package com.example.demo.controller;

import com.example.demo.entity.User;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@EnableAutoConfiguration
@RequestMapping("/boot")
public class TestBootController {
    @RequestMapping("/user")
    public User getUser(){
        User user = new User();
        user.setName("boot_test");
        return user;
    }
}

Spring boot啟動(dòng)默認(rèn)是要加載數(shù)據(jù)源的，所以我們在src/main/resources下新建application.yml

數(shù)據(jù)庫使用的是mysql。可根據(jù)自己的需求更換數(shù)據(jù)庫

#默認(rèn)使用配置
spring:
  profiles:
    active: dev
    
#公共配置與profiles選擇無關(guān)
mybatis:
  typeAliasesPackage: com.example.demo.entity
  mapperLocations: classpath:mapper/*.xml
  
---  #分隔線不能少

#開發(fā)配置
spring:
  profiles: dev

  datasource:
    url: jdbc:mysql://localhost:3306/test       #數(shù)據(jù)庫地址+數(shù)據(jù)庫名字(自定義)
    username: root                              #帳號(自定義)
    password: root                              #密碼(自定義)
    driver-class-name: com.mysql.jdbc.Driver    #驅(qū)動(dòng)

將pom.xml中加載數(shù)據(jù)源的jar包先注釋掉也可以。

/*<dependency>
   <groupId>org.mybatis.spring.boot</groupId>
   <artifactId>mybatis-spring-boot-starter</artifactId>
   <version>1.3.0</version>
</dependency>*/

最終結(jié)構(gòu)springboot目錄如下

啟動(dòng)DemoApplication的main方法，訪問http://localhost:8080/boot/user即可

ps:如果自定義了包名等~復(fù)制代碼請注意修改對應(yīng)包名

三、整合Mybatis

1、集成druid，使用連接池。pom.xml中添加：

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.1.0</version>
</dependency>

最終的pom.xml文件：

<?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.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>demo</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.3.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.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.2</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.0</version>
        </dependency>
    </dependencies>

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


</project>

到此Spring boot 就完成整合了~ 可以運(yùn)行測試下能否順利運(yùn)行。

2.用MyBatis Generator自動(dòng)生成代碼，或者自定義編寫各層

最終目錄請看文章最后

public class User {
    private Integer id;

    private String userName;

    private String password;

    private Integer age;
    
    //省略get set方法...
}

public interface UserDao {
    int insertSelective(User record);

    User selectByPrimaryKey(Integer id);
}

UserMapper.xml 中注意替換成自己的User對象地址 type 和parameterType

<?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.xc.dao.UserDao" ><!--修改自定義地址 -->
    <resultMap id="BaseResultMap" type="com.xc.entity.User" ><!--修改自定義地址 -->
        <id column="id" property="id" jdbcType="INTEGER" />
        <result column="user_name" property="userName" jdbcType="VARCHAR" />
        <result column="password" property="password" jdbcType="VARCHAR" />
        <result column="age" property="age" jdbcType="INTEGER" />
    </resultMap>
    <sql id="Base_Column_List" >
        id, user_name, password, age
    </sql>
    <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
        select
        <include refid="Base_Column_List" />
        from user_t
        where id = #{id,jdbcType=INTEGER}
    </select>
    <insert id="insertSelective" parameterType="com.xc.entity.User" ><!--修改自定義地址 -->
        insert into user_t
        <trim prefix="(" suffix=")" suffixOverrides="," >
            <if test="id != null" >
                id,
            </if>
            <if test="userName != null" >
                user_name,
            </if>
            <if test="password != null" >
                password,
            </if>
            <if test="age != null" >
                age,
            </if>
        </trim>
        <trim prefix="values (" suffix=")" suffixOverrides="," >
            <if test="id != null" >
                #{id,jdbcType=INTEGER},
            </if>
            <if test="userName != null" >
                #{userName,jdbcType=VARCHAR},
            </if>
            <if test="password != null" >
                #{password,jdbcType=VARCHAR},
            </if>
            <if test="age != null" >
                #{age,jdbcType=INTEGER},
            </if>
        </trim>
    </insert>
</mapper>

3.修改DemoApplication.java，添加掃描dao層接口。

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

@SpringBootApplication
@MapperScan("com.example.demo.dao") //修改成自己的dao地址
public class DemoApplication {

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

4.添加Service/impl 和Controller層

public interface UserService {
    public User getUserById(int userId);

    boolean addUser(User record);
}

@Service("userService")
public class UserServiceImpl implements UserService {
    @Resource
    private UserDao userDao;
    @Override
    public User getUserById(int userId) {
        return userDao.selectByPrimaryKey(userId);
    }

    @Override
    public boolean addUser(User record) {
        boolean result = false;
        try {
            userDao.insertSelective(record);
            result = true;
        } catch (Exception e) {
            e.printStackTrace();
        }

        return  result;
    }
}

@RestController
@EnableAutoConfiguration
@RequestMapping("/boot")
public class TestBootController {
    @Resource
    private UserService userService;
    @RequestMapping("/user")
    @ResponseBody
    public User getUser(HttpServletRequest request, Model model){
        int userId = Integer.parseInt(request.getParameter("id"));
        User user = this.userService.getUserById(userId);
        return user;
    }
}

5.Mysql創(chuàng)建測試表和插入數(shù)據(jù)

DROP TABLE IF EXISTS `user_t`;
CREATE TABLE `user_t` (
  `id` int(11) NOT NULL DEFAULT '0',
  `user_name` varchar(255) DEFAULT NULL,
  `password` varchar(255) DEFAULT NULL,
  `age` int(255) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of user_t
-- ----------------------------
INSERT INTO `user_t` VALUES ('0', 'bb', 'bb', '11');
INSERT INTO `user_t` VALUES ('1', 'aa', 'aaa', '11');

6.瀏覽器訪問http://localhost:8080/boot/user?id=1

最終結(jié)果展示

7.最終項(xiàng)目結(jié)構(gòu)圖

最終項(xiàng)目結(jié)構(gòu)圖