【Spring boot】IDEA + Maven + Spring Boot + Mybatis + Druid + PageHelper

    在第一篇Spring Boot 框架搭建博客中，底层用的是jpa，这篇博客底层选择的mybatis，之前搭建过Spring Boot + Mybatis的框架，用的是Spring Boot 1.5.9.RELEASE 版本，也没有配置数据连接池，这次选择的Spring Boot 2.0.1.RELEASE 版本，也加上了Druid数据库连接池和PageHelper分页插件。

     搭建过程如下：

一. 创建项目，选择相关的一些依赖

其他依赖添加：

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.datatype</groupId>
            <artifactId>jackson-datatype-joda</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.module</groupId>
            <artifactId>jackson-module-parameter-names</artifactId>
        </dependency>
        <!-- 分页插件 -->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper</artifactId>
            <version>5.1.3</version>
        </dependency>
        <!-- alibaba的druid数据库连接池 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.0</version>
        </dependency>

mybatis generator 插件添加：

            <!-- mybatis generator 自动生成代码插件 -->
            <plugin>
                <groupId>org.mybatis.generator</groupId>
                <artifactId>mybatis-generator-maven-plugin</artifactId>
                <version>1.3.2</version>
                <configuration>
                    <configurationFile>${basedir}/src/main/resources/generator/generatorConfig.xml</configurationFile>
                    <overwrite>true</overwrite>
                    <verbose>true</verbose>
                </configuration>
            </plugin>

二. 修改配置文件，同样使用更加简洁的application.yml文件，内容如下：

server:
  port: 7901

spring:
    datasource:
        url: jdbc:mysql://localhost:3306/uqi-user
        username: root
        password: 123456
       # 使用druid数据源
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: com.mysql.jdbc.Driver
        filters: stat
        maxActive: 20
        initialSize: 1
        maxWait: 60000
        minIdle: 1
        timeBetweenEvictionRunsMillis: 60000
        minEvictableIdleTimeMillis: 300000
        validationQuery: select 'x'
        testWhileIdle: true
        testOnBorrow: false
        testOnReturn: false
        poolPreparedStatements: true
        maxPoolPreparedStatementPerConnectionSize: 20
        maxOpenPreparedStatements: 20
mybatis:
  mapper-locations: classpath:mapping/*.xml
  type-aliases-package: com.uqiauto.user.model

mapper:
  mappers:  com.uqiauto.user.dao
  not-empty: false
  identity: MYSQL

#pagehelper分页插件
pagehelper:
    helperDialect: mysql
    rowBoundsWithCount: true
    pageSizeZero: true
    reasonable: true
    supportMethodsArguments: true
    params: count=countSql
    returnPageInfo: check

三. 使用mybatis generator 自动生成代码，配置pom.xml中generator插件对应的配置文件：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE generatorConfiguration
        PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">
<generatorConfiguration>
    <!-- 数据库驱动:选择你的本地硬盘上面的数据库驱动包-->
    <classPathEntry  location="D:\MybatisAuto\mysql-connector-java-5.1.20.jar"/>
    <context id="DB2Tables"  targetRuntime="MyBatis3">
        <commentGenerator>
            <property name="suppressDate" value="true"/>
            <!-- 是否去除自动生成的注释 true：是 ： false:否 -->
            <property name="suppressAllComments" value="true"/>
        </commentGenerator>
        <!--数据库链接URL，用户名、密码 -->
        <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://127.0.0.1/uqi-user" userId="root" password="123456">
        </jdbcConnection>
        <javaTypeResolver>
            <property name="forceBigDecimals" value="false"/>
        </javaTypeResolver>
        <!-- 生成模型的包名和位置-->
        <javaModelGenerator targetPackage="com.uqiauto.user.model" targetProject="src/main/java">
            <property name="enableSubPackages" value="true"/>
            <property name="trimStrings" value="true"/>
        </javaModelGenerator>
        <!-- 生成映射文件的包名和位置-->
        <sqlMapGenerator targetPackage="mapping" targetProject="src/main/resources">
            <property name="enableSubPackages" value="true"/>
        </sqlMapGenerator>
        <!-- 生成DAO的包名和位置-->
        <javaClientGenerator type="XMLMAPPER" targetPackage="com.uqiauto.user.dao" targetProject="src/main/java">
            <property name="enableSubPackages" value="true"/>
        </javaClientGenerator>
        <!-- 要生成的表 tableName是数据库中的表名或视图名 domainObjectName是实体类名-->
        <table tableName="sys_user" domainObjectName="User" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"></table>
    </context>
</generatorConfiguration>

四. 添加自动生成代码相关配置，点击 run - Edit Configurations，添加maven配置：

运行之后，可以在项目中看到对应生成的文件夹及代码：

五. 底层的一些配置都准备好了，因为Spring Boot 2.0版本，还需要添加一些Durid，DataSource，PageHelper的相关配置类：

DruidConfig：

@Configuration
public class DruidDBConfig {
    private Logger logger = LoggerFactory.getLogger(DruidDBConfig.class);

    @Value("${spring.datasource.url}")
    private String dbUrl;

    @Value("${spring.datasource.username}")
    private String username;

    @Value("${spring.datasource.password}")
    private String password;

    @Value("${spring.datasource.driver-class-name}")
    private String driverClassName;

    @Value("${spring.datasource.initialSize}")
    private int initialSize;

    @Value("${spring.datasource.minIdle}")
    private int minIdle;

    @Value("${spring.datasource.maxActive}")
    private int maxActive;

    @Value("${spring.datasource.maxWait}")
    private int maxWait;

    @Value("${spring.datasource.timeBetweenEvictionRunsMillis}")
    private int timeBetweenEvictionRunsMillis;

    @Value("${spring.datasource.minEvictableIdleTimeMillis}")
    private int minEvictableIdleTimeMillis;

    @Value("${spring.datasource.validationQuery}")
    private String validationQuery;

    @Value("${spring.datasource.testWhileIdle}")
    private boolean testWhileIdle;

    @Value("${spring.datasource.testOnBorrow}")
    private boolean testOnBorrow;

    @Value("${spring.datasource.testOnReturn}")
    private boolean testOnReturn;

    @Value("${spring.datasource.poolPreparedStatements}")
    private boolean poolPreparedStatements;

    @Value("${spring.datasource.maxPoolPreparedStatementPerConnectionSize}")
    private int maxPoolPreparedStatementPerConnectionSize;

    @Value("${spring.datasource.filters}")
    private String filters;

    @Value("{spring.datasource.connectionProperties}")
    private String connectionProperties;

    @Bean     //声明其为Bean实例
    @Primary  //在同样的DataSource中，首先使用被标注的DataSource
    public DataSource dataSource() {
        DruidDataSource datasource = new DruidDataSource();

        datasource.setUrl(this.dbUrl);
        datasource.setUsername(username);
        datasource.setPassword(password);
        datasource.setDriverClassName(driverClassName);

        //configuration
        datasource.setInitialSize(initialSize);
        datasource.setMinIdle(minIdle);
        datasource.setMaxActive(maxActive);
        datasource.setMaxWait(maxWait);
        datasource.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRunsMillis);
        datasource.setMinEvictableIdleTimeMillis(minEvictableIdleTimeMillis);
        datasource.setValidationQuery(validationQuery);
        datasource.setTestWhileIdle(testWhileIdle);
        datasource.setTestOnBorrow(testOnBorrow);
        datasource.setTestOnReturn(testOnReturn);
        datasource.setPoolPreparedStatements(poolPreparedStatements);
        datasource.setMaxPoolPreparedStatementPerConnectionSize(maxPoolPreparedStatementPerConnectionSize);
        try {
            datasource.setFilters(filters);
        } catch (SQLException e) {
            logger.error("druid configuration initialization filter", e);
        }
        datasource.setConnectionProperties(connectionProperties);

        return datasource;
    }
}

DataSourceConfig：

@Configuration
@MapperScan("com.uqiauto.user.dao")
@EnableTransactionManagement
public class DataSourceConfig {
    private static Logger logger = LoggerFactory.getLogger(DataSourceConfig.class);

    @Autowired
    private Environment env;

    @Autowired
    private PageInterceptor pageInterceptor;

    @Bean
    public SqlSessionFactory sqlSessionFactory(DataSource dataSource) throws Exception {
        SqlSessionFactoryBean fb = new SqlSessionFactoryBean();
        fb.setDataSource(dataSource);
        //该配置非常的重要，如果不将PageInterceptor设置到SqlSessionFactoryBean中，导致分页失效
        fb.setPlugins(new Interceptor[]{pageInterceptor});
        fb.setTypeAliasesPackage(env.getProperty("mybatis.type-aliases-package"));
        fb.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(env.getProperty("mybatis.mapper-locations")));
        return fb.getObject();
    }
}

PageHelperConfig：

@Configuration
public class PageHelperConfig {
    @Value("${pagehelper.helperDialect}")
    private String helperDialect;


    @Bean
    public PageInterceptor pageInterceptor(){
        PageInterceptor pageInterceptor = new PageInterceptor();
        Properties properties = new Properties();
        properties.setProperty("helperDialect", helperDialect);
        pageInterceptor.setProperties(properties);
        return pageInterceptor;
    }
}

六. 相关的业务逻辑层

@Service
@Transactional
public class UserService {

    @Resource
    private UserMapper userMapper;

    public int addUser(User user) {
        return userMapper.insertSelective(user);
    }

    /*
    * 这个方法中用到了我们开头配置依赖的分页插件pagehelper
    * 很简单，只需要在service层传入参数，然后将参数传递给一个插件的一个静态方法即可；
    * pageNum 开始页数
    * pageSize 每页显示的数据条数
    * */
    public PageInfo<User> findAllUser(int pageNum, int pageSize) {
        PageHelper.startPage(pageNum, pageSize);
        List<User> userList=userMapper.selectAllUser();
        //取分页后结果
        PageInfo<User> pageInfo=new PageInfo<User>(userList);
        return pageInfo;
    }
}

七. 相关的控制层

@RestController
@RequestMapping(value = "/uplus")
public class UserController {

    @Autowired
    private UserService userService;

    @ResponseBody
    @RequestMapping(value = "/user/add", produces = {"application/json;charset=UTF-8"})
    public int addUser(User user){
        return userService.addUser(user);
    }

    @ResponseBody
    @GetMapping("/user/all")
    public Map<String,Object> findAllUser(
            @RequestParam(name = "pageNum", required = false, defaultValue = "1")
                    int pageNum,
            @RequestParam(name = "pageSize", required = false, defaultValue = "10")
                    int pageSize){
        Map<String,Object> result=new HashMap<>();
        //开始分页
        PageHelper.startPage(pageNum,pageSize);
        PageInfo<User> userPageInfo= userService.findAllUser(pageNum,pageSize);
        result.put("total",userPageInfo.getTotal());
        result.put("rows",userPageInfo.getList());
        result.put("pages",userPageInfo.getPages());
        return result;
    }
}

八. 测试
    我们直接采用IDEA开发工具中提供的接口测试工具测试

1）新增用户 (uplus/user/add)

2）获取所有用户，结果分页显示 (uplus/user/all)

九. 项目源码gitHub地址：
https://github.com/huzhiting/spring-boot-mybatis