package com.tao.utils;
import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.ResultSetMetaData;import java.sql.SQLException;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;
import org.springframework.stereotype.Repository;
/** * @author 陈建 * @描述：dao基础类 * 2018-10-25下午2:54:57 */@Repositorypublic class BaseDao { //四大金刚 static String driver="com.mysql.jdbc.Driver"; static String url="jdbc:mysql://localhost:3306/day35?useSSL=false"; static String user="root"; static String password="root"; //加载驱动 static{ try { Class.forName(driver); } catch (ClassNotFoundException e) { e.printStackTrace(); } } //获取数据库连接 public static Connection getConnection() { try { return DriverManager.getConnection(url, user, password); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null;
} //关闭数据库连接 public static void closeConnection(Connection conn ,PreparedStatement ps ,ResultSet rs) { if(rs!=null){ try { rs.close(); } catch (SQLException e) { e.printStackTrace(); } } if(ps!=null){ try { ps.close(); } catch (SQLException e) { e.printStackTrace(); } } if(conn!=null){ try { conn.close(); } catch (SQLException e) { e.printStackTrace(); } }
} //查询通用方法 public List<Map<String,Object>> executeQuery(String sql,Object...params) { List<Map<String,Object>> objList= new ArrayList<Map<String,Object>>(); Connection conn = getConnection(); PreparedStatement ps=null; ResultSet rs=null; try { ps = conn.prepareStatement(sql); ps = setParams(ps, params); //执行sql rs = ps.executeQuery(); //获取表元数据信息 ResultSetMetaData metaData = rs.getMetaData(); //解析结果集 while(rs.next()){ Map<String,Object> row= new HashMap<String, Object>(); //metaData.getColumnCount()获取列数 for (int i = 0; i < metaData.getColumnCount(); i++) { row.put(metaData.getColumnName(i+1), rs.getObject(i+1)); } objList.add(row); } } catch (SQLException e) { e.printStackTrace(); }finally{ closeConnection(conn, ps, rs); } return objList;
} //增删改通用方法 public boolean executeUpdate(String sql,Object...params) { Connection conn = getConnection(); PreparedStatement ps=null; try { ps = conn.prepareStatement(sql); ps = setParams(ps, params); //执行sql int ret = ps.executeUpdate(); if(ret>0){ System.out.println("操作成功！"); return true; }else { System.out.println("操作失败！"); return false; } } catch (SQLException e) { e.printStackTrace(); }finally{ closeConnection(conn, ps, null); } return false;
} //设值通用方法 public PreparedStatement setParams(PreparedStatement ps,Object...params) { if(params!=null){ for (int i = 0; i < params.length; i++) { try { ps.setObject(i+1, params[i]); } catch (SQLException e) { e.printStackTrace(); } } } return ps;
}
}
转载于:https://www.cnblogs.com/foreverone/p/10634760.html
相关资源：java泛型BaseDao与BaseService