SpringBoot中封装jdbc工具类

背景

现在的数据层的开发，大多会使用如MyBatis或JPA之类的开发工具。这些开发工具给我们的开发过程中带来了极大的便利。
但是在一些极端的场景下往往原生的jdbc方式操作数据库更灵活，性能更高。由于部分场景下MyBatis或JPA之类无法满足我的需求，所以我打算自己封装一套查数据库的工具类。

具体实现

pom.xml

我们会用到fastjson,druid,mysql所以pom.xml增加依赖如下：

<dependency>
    <groupId>com.alibabagroupId>
    <artifactId>fastjsonartifactId>
    <version>1.2.62version>
dependency>
<dependency>
    <groupId>com.alibabagroupId>
    <artifactId>druidartifactId>
    <version>1.1.9version>
dependency>

<dependency>
    <groupId>mysqlgroupId>
    <artifactId>mysql-connector-javaartifactId>
dependency>

cn/ycmit/jdbcutil/util/JdbcUtil.java

以下是核心代码部分

package cn.ycmit.jdbcutil.util;

import cn.ycmit.jdbcutil.domain.DataSource;
import cn.ycmit.jdbcutil.dto.ResponseDto;
import com.alibaba.druid.pool.DruidPooledConnection;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import lombok.extern.slf4j.Slf4j;

import java.sql.*;
import java.util.ArrayList;
import java.util.List;

@Slf4j
public class JdbcUtil {
    /**
     * 执行sql并返回结果
     *
     * @param datasource      数据源连接
     * @param sql             语句
     */
    public static ResponseDto executeSql(DataSource datasource, String sql) {
        return executeSql(datasource,sql,new ArrayList<Object>());
    }

    /**
     * 执行sql并返回结果
     *
     * @param datasource      数据源连接
     * @param sql             语句
     * @param jdbcParamValues
     */
    public static ResponseDto executeSql(DataSource datasource, String sql, List<Object> jdbcParamValues) {
        log.debug(sql);
        log.debug(JSON.toJSONString(jdbcParamValues));
        DruidPooledConnection connection = null;
        try {
            connection = PoolManager.getPooledConnection(datasource);
            PreparedStatement statement = connection.prepareStatement(sql);
            for (int i = 1; i <= jdbcParamValues.size(); i++) {
                statement.setObject(i, jdbcParamValues.get(i - 1));
            }
            boolean hasResultSet = statement.execute();
            if (hasResultSet) {
                ResultSet rs = statement.getResultSet();
                int columnCount = rs.getMetaData().getColumnCount();
                List<String> columns = new ArrayList<>();
                for (int i = 1; i <= columnCount; i++) {
                    String columnName = rs.getMetaData().getColumnLabel(i);
                    columns.add(columnName);
                }
                List<JSONObject> list = new ArrayList<>();
                while (rs.next()) {
                    JSONObject jo = new JSONObject();
                    columns.stream().forEach(t -> {
                        try {
                            Object value = rs.getObject(t);
                            jo.put(t, value);

                        } catch (SQLException e) {
                            e.printStackTrace();
                        }
                    });
                    list.add(jo);
                }
                return ResponseDto.apiSuccess(list);
            } else {
                int updateCount = statement.getUpdateCount();
                return ResponseDto.apiSuccess("sql修改数据行数：" + updateCount);
            }
        } catch (Exception e) {
            e.printStackTrace();
            return ResponseDto.fail(e.getMessage());
        } finally {
            try {
                if (connection != null) {
                    connection.close();
                }
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}

PoolManager

jdbcutil/src/main/java/cn/ycmit/jdbcutil/util/PoolManager.java
代码如下：

package cn.ycmit.jdbcutil.util;

import cn.ycmit.jdbcutil.domain.DataSource;
import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.pool.DruidPooledConnection;
import lombok.extern.slf4j.Slf4j;

import java.sql.SQLException;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;


/**
 * 数据库连接池工具类
 */
@Slf4j
public class PoolManager {

    private static Lock lock = new ReentrantLock();

    private static Lock deleteLock = new ReentrantLock();

    //所有数据源的连接池存在map里
    static Map<String, DruidDataSource> map = new HashMap<>();

    public static DruidDataSource getJdbcConnectionPool(DataSource ds) {
        if (map.containsKey(ds.getId())) {
            return map.get(ds.getId());
        } else {
            lock.lock();
            try {
                log.info(Thread.currentThread().getName() + "获取锁");
                if (!map.containsKey(ds.getId())) {
                    DruidDataSource druidDataSource = new DruidDataSource();
                    druidDataSource.setName(ds.getName());
                    druidDataSource.setUrl(ds.getUrl());
                    druidDataSource.setUsername(ds.getUsername());
                    druidDataSource.setPassword(ds.getPassword());
                    druidDataSource.setDriverClassName(ds.getDriver());
                    druidDataSource.setConnectionErrorRetryAttempts(3);       //失败后重连次数
                    druidDataSource.setBreakAfterAcquireFailure(true);

                    map.put(ds.getId(), druidDataSource);
                    log.info("创建Druid连接池成功：{}", ds.getName());
                }
                return map.get(ds.getId());
            } catch (Exception e) {
                return null;
            } finally {
                lock.unlock();
            }
        }
    }

    //删除数据库连接池
    public static void removeJdbcConnectionPool(String id) {
        deleteLock.lock();
        try {
            DruidDataSource druidDataSource = map.get(id);
            if (druidDataSource != null) {
                druidDataSource.close();
                map.remove(id);
            }
        } catch (Exception e) {
            log.error(e.toString());
        } finally {
            deleteLock.unlock();
        }

    }

    public static DruidPooledConnection getPooledConnection(DataSource ds) throws SQLException {
        DruidDataSource pool = PoolManager.getJdbcConnectionPool(ds);
        DruidPooledConnection connection = pool.getConnection();
//        log.info("获取连接成功");
        return connection;
    }
}

ResponseDto

jdbcutil/src/main/java/cn/ycmit/jdbcutil/dto/ResponseDto.java
代码如下：

package cn.ycmit.jdbcutil.dto;

import lombok.Data;
/**
 * 返回值包装类
 */
@Data
public class ResponseDto {
    String msg;
    Object data;
    boolean success;
    public static ResponseDto apiSuccess(Object data) {
        ResponseDto dto = new ResponseDto();
        dto.setData(data);
        dto.setSuccess(true);
        dto.setMsg("接口访问成功");
        return dto;
    }

    public static ResponseDto successWithMsg(String msg) {
        ResponseDto dto = new ResponseDto();
        dto.setData(null);
        dto.setSuccess(true);
        dto.setMsg(msg);
        return dto;
    }

    public static ResponseDto successWithData(Object data) {
        ResponseDto dto = new ResponseDto();
        dto.setData(data);
        dto.setSuccess(true);
        return dto;
    }

    public static ResponseDto fail(String msg) {
        ResponseDto dto = new ResponseDto();
        dto.setSuccess(false);
        dto.setMsg(msg);
        return dto;
    }
}

DataSource.java

jdbcutil/src/main/java/cn/ycmit/jdbcutil/domain/DataSource.java
代码如下：

package cn.ycmit.jdbcutil.domain;

import lombok.Data;

/**
 * 数据源实体类
 *
 */
@Data
public class DataSource {
    String id;
    String name;
    String url;
    String username;
    String password;
    String driver;
}

JdbcDemoController

jdbcutil/src/main/java/cn/ycmit/jdbcutil/controller/JdbcDemoController.java

package cn.ycmit.jdbcutil.controller;

import cn.ycmit.jdbcutil.domain.DataSource;
import cn.ycmit.jdbcutil.dto.ResponseDto;
import cn.ycmit.jdbcutil.util.JdbcUtil;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

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

@RestController
public class JdbcDemoController {
    public static DataSource ds = new DataSource();
    static {
        //配置数据源
        ds.setId("1");
        ds.setName("mysql");
        ds.setUrl("jdbc:mysql://172.16.184.23:3307/dbapi?useSSL=false&characterEncoding=UTF-8&serverTimezone=GMT%2B8");
        ds.setUsername("root");
        ds.setPassword("itkey123456");
        ds.setDriver("com.mysql.cj.jdbc.Driver");
    }

    /**
     * 查询测试
     * @return
     */
    @RequestMapping("/api/list")
    public ResponseDto queryList()
    {
        String sql = "show tables";
        ResponseDto responseDto = JdbcUtil.executeSql(ds,sql);
        return responseDto;
    }
}

效果测试

源码下载

https://download.csdn.net/download/lxyoucan/85094574

参考

https://github.com/freakchick/DBApi