Java使用Alibaba Druid数据库连接池的技术指南

<!-- mybatis-plus -->
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.3.1</version>
</dependency>
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.19</version>
</dependency>
<!-- druid -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid-spring-boot-starter</artifactId>
    <version>1.2.16</version>
</dependency>
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <version>1.18.34</version>
    <scope>provided</scope>
</dependency>

spring:
  datasource:
    druid:
      driver-class-name: com.mysql.cj.jdbc.Driver
      url: jdbc:mysql://192.168.22.181:3306/shop_admin?useUnicode=true&characterEncoding=UTF-8&useSSL=false&serverTimezone=Asia/Shanghai
      username: shop
      password: 123456
      initial-size: 5               # 初始化连接数
      min-idle: 5                   # 最小空闲连接数
      max-active: 20                # 最大连接数
      max-wait: 60000               # 获取连接等待超时时间
      time-between-eviction-runs-millis: 60000 # 检测空闲连接的间隔
      min-evictable-idle-time-millis: 300000  # 最小空闲时间
      validation-query: SELECT 1    # 验证连接有效性 SQL
      test-on-borrow: false         # 借用连接时是否测试
      test-on-return: false         # 归还连接时是否测试
      test-while-idle: true         # 空闲时测试连接
      stat-view-servlet:
        enabled: true
        login-username: admin      # Druid 监控页用户名
        login-password: admin123      # Druid 监控页密码
      web-stat-filter:
        enabled: true
        exclusions: "*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*" # 排除的 URL

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import com.alibaba.druid.pool.DruidDataSource;

import javax.sql.DataSource;

@Configuration
public class DataSourceConfig {

    @Bean
    public DataSource dataSource() {
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setUrl("jdbc:mysql://192.168.22.181:3306/shop_admin?useSSL=false&serverTimezone=UTC");
        dataSource.setUsername("shop");
        dataSource.setPassword("123456");
        dataSource.setDriverClassName("com.mysql.cj.jdbc.Driver");

        // Druid 特有配置
        dataSource.setInitialSize(5);      // 初始化连接数
        dataSource.setMaxActive(20);       // 最大连接数
        dataSource.setMinIdle(5);          // 最小空闲连接数
        dataSource.setMaxWait(60000);      // 最大等待时间
        dataSource.setValidationQuery("SELECT 1"); // 验证 SQL
        dataSource.setTestOnBorrow(false);
        dataSource.setTestOnReturn(false);
        dataSource.setTestWhileIdle(true);
        return dataSource;
    }
}

package com.lm.druid.service;

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.lm.druid.entry.SysUserEntity;
import com.lm.druid.mapper.SysUserMapper;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;

@Service
public class UserService extends ServiceImpl<SysUserMapper, SysUserEntity> {

    @Resource
    private SysUserMapper sysUserMapper;

    public SysUserEntity getUserById(Long id){
        return sysUserMapper.selectById(id);
    }
}

package com.lm.druid.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.lm.druid.entry.SysUserEntity;

public interface SysUserMapper extends BaseMapper<SysUserEntity> {
}

package com.lm.druid.entry;

import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;

import java.io.Serializable;
import java.util.Date;

@Data
@TableName("sys_user")
public class SysUserEntity implements Serializable {
    private static final long serialVersionUID = 1L;

    /**
     * 用户ID
     */
    @TableId(value = "user_id")
    private Long userId;

    /**
     * 用户名
     */
    @TableField("username")
    private String username;

    /**
     * 密码
     */
    @TableField("password")
    private String password;

    /**
     * 盐
     */
    @TableField("salt")
    private String salt;

    /**
     * 邮箱
     */
    @TableField("email")
    private String email;

    /**
     * 手机号
     */
    @TableField("mobile")
    private String mobile;

    /**
     * 状态  0：禁用   1：正常
     */
    @TableField("status")
    private Integer status;

    /**
     * 创建者ID
     */
    @TableField("create_user_id")
    private Long createUserId;

    /**
     * 创建时间
     */
    @TableField("create_time")
    private Date createTime;
}

package com.lm.druid.controller;

import com.lm.druid.entry.SysUserEntity;
import com.lm.druid.service.UserService;
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.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.Date;

@RestController
@RequestMapping("/user")
public class UserController {

    @Autowired
    private UserService userService;


    @GetMapping("/getUserByIntId")
    public SysUserEntity getUserByIntId(@RequestParam Long id) {
        return userService.getUserById(id);
    }
}

@SpringBootApplication
@MapperScan("com.lm.druid.mapper")
public class DruidApplication {
    public static void main(String[] args) {
        SpringApplication.run(DruidApplication.class, args);
    }
}