Mybatis plus 配置

1. 添加依赖

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.3.1.tmp</version>
</dependency>

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

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-generator</artifactId>
    <version>3.3.1.tmp</version>
</dependency>

<dependency>
    <groupId>org.apache.velocity</groupId>
    <artifactId>velocity-engine-core</artifactId>
    <version>2.2</version>
</dependency>

<dependency>
    <groupId>org.freemarker</groupId>
    <artifactId>freemarker</artifactId>
    <version>2.3.30</version>
</dependency>

<dependency>
    <groupId>com.ibeetl</groupId>
    <artifactId>beetl</artifactId>
    <version>3.1.6.RELEASE</version>
</dependency>

2.  分页插件

@Configuration
public class MybatisPlusConfig {
    @Bean
    public PaginationInterceptor paginationInterceptor() {
        PaginationInterceptor paginationInterceptor = new PaginationInterceptor();
        // 设置请求的页面大于最大页后操作， true调回到首页，false 继续请求  默认false
        // paginationInterceptor.setOverflow(false);
        // 设置最大单页限制数量，默认 500 条，-1 不受限制
        //paginationInterceptor.setLimit(500);
        // 开启 count 的 join 优化,只针对部分 left join
        //paginationInterceptor.setCountSqlParser(new JsqlParserCountOptimize(true));
        return paginationInterceptor;
    }
}

3.  继承BaseMapper<T>

public interface UserMapper extends BaseMapper<User> {}

4. 启动类添加Mapper接口扫描

@SpringBootApplication
@MapperScan(basePackages = "com.royal.home.mapper")
public class HomeApplication {
    public static void main(String[] args) {
        SpringApplication.run(HomeApplication.class, args);
    }
}

5. 代码生成

package com.royal.home.AutoGenerator;

import com.baomidou.mybatisplus.core.exceptions.MybatisPlusException;
import com.baomidou.mybatisplus.core.toolkit.StringPool;
import com.baomidou.mybatisplus.generator.AutoGenerator;
import com.baomidou.mybatisplus.generator.InjectionConfig;
import com.baomidou.mybatisplus.generator.config.*;
import com.baomidou.mybatisplus.generator.config.po.TableInfo;
import com.baomidou.mybatisplus.generator.config.rules.NamingStrategy;
import com.baomidou.mybatisplus.generator.engine.FreemarkerTemplateEngine;
import org.apache.commons.lang3.StringUtils;

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

/**
 * <p>
 * CodeGenerator
 * </p>
 *
 * @author zpf
 * @since 2020-05-11
 */
// 演示例子，执行 main 方法控制台输入模块表名回车自动生成对应项目目录中
public class CodeGenerator {

    /**
     * <p>
     * 读取控制台内容
     * </p>
     */
    public static String scanner(String tip) {
        Scanner scanner = new Scanner(System.in);
        StringBuilder help = new StringBuilder();
        help.append("请输入" + tip + "：");
        System.out.println(help.toString());
        if (scanner.hasNext()) {
            String ipt = scanner.next();
            if (StringUtils.isNotEmpty(ipt)) {
                return ipt;
            }
        }
        throw new MybatisPlusException("请输入正确的" + tip + "！");
    }

    public static void main(String[] args) {
        // 代码生成器
        AutoGenerator mpg = new AutoGenerator();

        // 全局配置
        GlobalConfig gc = new GlobalConfig();
        String projectPath = System.getProperty("user.dir");
        gc.setOutputDir(projectPath + "/src/main/java");
        gc.setAuthor("3hzpf");
        gc.setOpen(false);
        // gc.setSwagger2(true); 实体属性 Swagger2 注解
        mpg.setGlobalConfig(gc);

        // 数据源配置
        DataSourceConfig dsc = new DataSourceConfig();
        dsc.setUrl("jdbc:mysql://localhost:3306/test?useUnicode=true&useSSL=false&characterEncoding=utf8&serverTimezone=UTC");
        // dsc.setSchemaName("public");
        dsc.setDriverName("com.mysql.jdbc.Driver");
        dsc.setUsername("root");
        dsc.setPassword("root");
        mpg.setDataSource(dsc);

        // 包配置
        PackageConfig pc = new PackageConfig();
        pc.setModuleName(scanner("模块名"));
        pc.setParent("com.royal");
        mpg.setPackageInfo(pc);

        // 自定义配置
        InjectionConfig cfg = new InjectionConfig() {
            @Override
            public void initMap() {
                // to do nothing
            }
        };

        // 如果模板引擎是 freemarker
        String templatePath = "/templates/mapper.xml.ftl";
        // 如果模板引擎是 velocity
        // String templatePath = "/templates/mapper.xml.vm";

        // 自定义输出配置
        List<FileOutConfig> focList = new ArrayList<>();
        // 自定义配置会被优先输出
        focList.add(new FileOutConfig(templatePath) {
            @Override
            public String outputFile(TableInfo tableInfo) {
                // 自定义输出文件名 ， 如果你 Entity 设置了前后缀、此处注意 xml 的名称会跟着发生变化！！
                return projectPath + "/src/main/resources/mapper/" + pc.getModuleName()
                        + "/" + tableInfo.getEntityName() + "Mapper" + StringPool.DOT_XML;
            }
        });
        /*
        cfg.setFileCreate(new IFileCreate() {
            @Override
            public boolean isCreate(ConfigBuilder configBuilder, FileType fileType, String filePath) {
                // 判断自定义文件夹是否需要创建
                checkDir("调用默认方法创建的目录，自定义目录用");
                if (fileType == FileType.MAPPER) {
                    // 已经生成 mapper 文件判断存在，不想重新生成返回 false
                    return !new File(filePath).exists();
                }
                // 允许生成模板文件
                return true;
            }
        });
        */
        cfg.setFileOutConfigList(focList);
        mpg.setCfg(cfg);

        // 配置模板
        TemplateConfig templateConfig = new TemplateConfig();

        // 配置自定义输出模板
        //指定自定义模板路径，注意不要带上.ftl/.vm, 会根据使用的模板引擎自动识别
        // templateConfig.setEntity("templates/entity2.java");
        // templateConfig.setService();
        // templateConfig.setController();

        templateConfig.setXml(null);
        mpg.setTemplate(templateConfig);

        // 策略配置
        StrategyConfig strategy = new StrategyConfig();
        strategy.setNaming(NamingStrategy.underline_to_camel);
        strategy.setColumnNaming(NamingStrategy.underline_to_camel);
        //strategy.setSuperEntityClass("你自己的父类实体,没有就不用设置!");
        strategy.setEntityLombokModel(true);
        strategy.setRestControllerStyle(true);
        // 公共父类
        //strategy.setSuperControllerClass("你自己的父类控制器,没有就不用设置!");
        // 写于父类中的公共字段
        //strategy.setSuperEntityColumns("id");
        strategy.setInclude(scanner("表名，多个英文逗号分割").split(","));
        strategy.setControllerMappingHyphenStyle(true);
        strategy.setTablePrefix(pc.getModuleName() + "_");
        mpg.setStrategy(strategy);
        mpg.setTemplateEngine(new FreemarkerTemplateEngine());
        mpg.execute();
    }
}

6. 具体实现

控制器类

package com.royal.home.controller;

import com.royal.home.entity.User;
import com.royal.home.service.IUserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;

/**
 * <p>
 *  前端控制器
 * </p>
 *
 * @author 3hzpf
 * @since 2020-05-11
 */
@RestController
@RequestMapping("/home/user")
public class UserController {

    @Autowired
    private IUserService userService;

    @GetMapping("/list")
    public List<User> getList(){
        User user = new User();
        return userService.list(user,1,10);
    }
}

实体类

package com.royal.home.entity;

import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import java.io.Serializable;
import lombok.Data;
import lombok.EqualsAndHashCode;
import lombok.experimental.Accessors;

/**
 * <p>
 * 
 * </p>
 *
 * @author zpf
 * @since 2020-05-11
 */
@Data
@EqualsAndHashCode(callSuper = false)
@Accessors(chain = true)
public class User implements Serializable {

    private static final long serialVersionUID = 1L;
    
    @TableId(value = "id", type = IdType.AUTO)
    private Integer id;
    private String name;
    private Integer age;
    private String email;
}

Mapper

package com.royal.home.mapper;

import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.royal.home.entity.User;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.apache.ibatis.annotations.Param;
/**
 * <p>
 *  Mapper 接口
 * </p>
 *
 * @author zpf
 * @since 2020-05-11
 */
public interface UserMapper extends BaseMapper<User> {

    Page<User> list(Page page,@Param("map") User user);
}

Service接口

package com.royal.home.service;

import com.royal.home.entity.User;
import com.baomidou.mybatisplus.extension.service.IService;

import java.util.List;
/**
 * <p>
 *  服务类
 * </p>
 *
 * @author 3hzpf
 * @since 2020-05-11
 */
public interface IUserService extends IService<User> {
    List<User> list(User searchBean, int page, int limit);
}

Service实现类

package com.royal.home.service.impl;

import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.royal.home.entity.User;
import com.royal.home.mapper.UserMapper;
import com.royal.home.service.IUserService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.springframework.stereotype.Service;

import java.util.List;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 3hzpf
 * @since 2020-05-11
 */
@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements IUserService {

    @Override
    public List<User> list(User searchBean, int page, int limit) {
        Page<User> userPage = baseMapper.list(new Page(page, limit),searchBean);
        List<User> userList = userPage.getRecords();
        return userList;
    }
}

UserMapper.xml

<?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.royal.home.mapper.UserMapper">
    <select id="list" resultType="com.royal.home.entity.User">
        SELECT u.id,u.name,u.age,u.email FROM user u WHERE 1=1
        <if test="map.name != null and map.name != ''">
            AND u.name like '%${map.name}%'
        </if>
        ORDER BY u.id
    </select>
</mapper>

7.  整体目录结构