SpringBoot整合mybatis实现Druid监控和数据分页

pom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.springboot.demo</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>2.0.4.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-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <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>

        <!-- 分页插件 -->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper-spring-boot-starter</artifactId>
            <version>1.2.5</version>
        </dependency>

        <!-- bootstrap -->
        <dependency>
            <groupId>org.webjars</groupId>
            <artifactId>bootstrap</artifactId>
            <version>4.1.3</version>
        </dependency>

        <!-- jq -->
        <dependency>
            <groupId>org.webjars</groupId>
            <artifactId>jquery</artifactId>
            <version>3.3.1-1</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.10</version>
        </dependency>

    </dependencies>

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


</project>

application.yml文件

spring:
  datasource:
#   数据源基本配置
    username: root
    password: 123456
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/mybatis?useUnicode=true&characterEncoding=utf-8&useSSL=false
    type: com.alibaba.druid.pool.DruidDataSource
#   数据源其他配置
    initialSize: 5
    minIdle: 5
    maxActive: 20
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECT 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true
#   配置监控统计拦截的filters，去掉后监控界面sql无法统计，'wall'用于防火墙
    filters: stat,wall
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500
    schema:
      - classpath:sql/department.sql
      - classpath:sql/employee.sql

#mybatis:
#  # 指定全局配置文件位置
#  config-location: classpath:mybatis/mybatis-config.xml
#  # 指定sql映射文件位置
#  mapper-locations: classpath:mybatis/mapper/*.xml


#pagehelper
pagehelper:
    helperDialect: mysql
    reasonable: true
    supportMethodsArguments: true
    params: count=countSql
    returnPageInfo: check

entity的实体类

public class Employee {

    private Integer id;
    private String lastName;
    private Integer gender;
    private String email;
    private Integer dId;

    // get set方法省去了
}

mybatis的注解mapper文件

import com.springboot.demo.entity.Employee;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;

import java.util.List;

@Mapper
public interface EmployeeDao {

    @Select("select * from employee where id = #{id}")
    Employee getById(Integer id);


    @Select("select * from employee")
    List<Employee> getAll();
}

service层的接口文件

public interface EmployeeService {

    Employee getOne(Integer id);

    PageInfo<Employee> getAll(Integer pageNum, Integer pageSize);

}

service层接口对应的实现类

import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import com.springboot.demo.dao.EmployeeDao;
import com.springboot.demo.entity.Employee;
import com.springboot.demo.service.EmployeeService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class EmployeeServiceImpl implements EmployeeService {

    @Autowired
    private EmployeeDao employeeDao;

    @Override
    public Employee getOne(Integer id) {
        return employeeDao.getById(id);
    }


    // 分页显示数据
    @Override
    public PageInfo<Employee> getAll(Integer pageNum, Integer pageSize) {
        PageHelper.startPage(pageNum, pageSize);
        List<Employee> employeeList = employeeDao.getAll();
        PageInfo result = new PageInfo(employeeList);
        return result;
    }
}

封装返回数据工具类

import java.util.List;

public class LayerMsg {
    private int code;
    private String msg;
    private long count;
    private List<Object> data;

    public int getCode() {
        return code;
    }

    public void setCode(int code) {
        this.code = code;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

    public long getCount() {
        return count;
    }

    public void setCount(long count) {
        this.count = count;
    }

    public List<Object> getData() {
        return data;
    }

    public void setData(List<Object> data) {
        this.data = data;
    }

    public LayerMsg() {
    }


    public static LayerMsg success(long total, List<Object> data){
        LayerMsg layerMsg = new LayerMsg();
        layerMsg.setCode(0);
        layerMsg.setMsg("获取数据成功！");
        layerMsg.setCount(total);
        layerMsg.setData(data);
        return layerMsg;
    }


    public static LayerMsg fail(){
        LayerMsg layerMsg = new LayerMsg();
        layerMsg.setCode(0);
        layerMsg.setMsg("获取数据失败！");
        layerMsg.setCount(0);
        layerMsg.setData(null);
        return layerMsg;
    }

}

控制器层

import com.github.pagehelper.PageInfo;
import com.springboot.demo.entity.Employee;
import com.springboot.demo.service.EmployeeService;
import com.springboot.demo.util.LayerMsg;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

// 实现rest风格的api
@RestController
public class MainController {

    @Autowired
    private EmployeeService employeeService;


    @GetMapping("/emp/{id}")
    public Employee show_one(@PathVariable("id") Integer id){
        return employeeService.getOne(id);
    }


    // 分页的显示数据
    @GetMapping("/emp")
    public LayerMsg pageList(@RequestParam(name = "pageNum", required = false, defaultValue = "1")
                                     int pageNum,
                             @RequestParam(name = "pageSize", required = false, defaultValue = "10")
                                     int pageSize){
        PageInfo page = employeeService.getAll(pageNum, pageSize);
        return LayerMsg.success(page.getTotal(), page.getList());
    }
}

配置Druid的数据监控

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.sql.DataSource;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;

@Configuration
public class DruidConfig {

    @ConfigurationProperties(prefix = "spring.datasource")
    @Bean
    public DataSource druid(){
        return  new DruidDataSource();
    }

    //配置Druid的监控
    //1、配置一个管理后台的Servlet
    @Bean
    public ServletRegistrationBean statViewServlet(){
        ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
        Map<String,String> initParams = new HashMap<>();

        initParams.put("loginUsername","admin");
        initParams.put("loginPassword","123456");
        initParams.put("allow","");//默认就是允许所有访问
//        initParams.put("deny","192.168.15.21");

        bean.setInitParameters(initParams);
        return bean;
    }


    //2、配置一个web监控的filter
    @Bean
    public FilterRegistrationBean webStatFilter(){
        FilterRegistrationBean bean = new FilterRegistrationBean();
        bean.setFilter(new WebStatFilter());

        Map<String,String> initParams = new HashMap<>();
        initParams.put("exclusions","*.js,*.css,/druid/*");

        bean.setInitParameters(initParams);

        bean.setUrlPatterns(Arrays.asList("/*"));

        return  bean;
    }
}

mybatis的配置类实现驼峰命名法

import org.apache.ibatis.session.Configuration;
import org.mybatis.spring.boot.autoconfigure.ConfigurationCustomizer;
import org.springframework.context.annotation.Bean;

@org.springframework.context.annotation.Configuration
public class MyBatisConfig {

    @Bean
    public ConfigurationCustomizer configurationCustomizer(){
        return new ConfigurationCustomizer(){

            @Override
            public void customize(Configuration configuration) {
                configuration.setMapUnderscoreToCamelCase(true);
            }
        };
    }
}

最后想吐槽下，有些人都不看自己的代码能不能使用，就发博客，很扎心！