JDBCUtilsByDruid类的模板与BasicDAO的模板

2023-08-30

JDBCUtilsByDruid类

import com.alibaba.druid.pool.DruidDataSourceFactory;

import javax.sql.DataSource;
import java.io.FileInputStream;
import java.io.IOException;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;


public class JDBCUtilsByDruid {
    private static DataSource ds;

    static {
        Properties properties = new Properties();
        try {
            properties.load(new FileInputStream("src\\druid.properties"));
            ds = DruidDataSourceFactory.createDataSource(properties);
        } catch (IOException e) {
            throw new RuntimeException(e);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }


    //获取连接
    public static Connection getConnection() throws SQLException {
        return ds.getConnection();
    }

    //关闭连接
    public static void close(ResultSet resultSet, Statement statement,Connection connection){
        try {
            if(resultSet!=null){
                resultSet.close();
            }
            if(statement!=null){
                statement.close();
            }
            if(connection!=null){
                connection.close();
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }
}

BasicDAO类

import com.hh.jdbc.datasource_.JDBCUtilsByDruid;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.ScalarHandler;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;

public class BasicDAO<T> {
    private static QueryRunner qr = new QueryRunner();

    //DML
    public int update(String sql,Object... parameter){
        Connection connection = null;
        try {
            connection = JDBCUtilsByDruid.getConnection();
            return qr.update(connection, sql, parameter);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        } finally {
            JDBCUtilsByDruid.close(null,null,connection);
        }
    }

    //查询返回多个对象
    public List<T> queryMulti(String sql,Class<T> clazz,Object... parameter){
        Connection connection = null;
        try {
            connection = JDBCUtilsByDruid.getConnection();
            return qr.query(connection,sql,new BeanListHandler<T>(clazz),parameter);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        } finally {
            JDBCUtilsByDruid.close(null,null,connection);
        }

    }

    //查询返回对象
    public T querySingle(String sql,Class<T> clazz,Object... parameter){
        Connection connection = null;
        try {
            connection = JDBCUtilsByDruid.getConnection();
            return qr.query(connection,sql,new BeanHandler<T>(clazz),parameter);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        } finally {
            JDBCUtilsByDruid.close(null,null,connection);
        }

    }

    //查询返回Object
    public Object queryScalar(String sql,Object... parameter){
        Connection connection = null;
        try {
            connection = JDBCUtilsByDruid.getConnection();
            return qr.query(connection,sql,new ScalarHandler(),parameter);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        } finally {
            JDBCUtilsByDruid.close(null,null,connection);
        }

    }
}