BaseDao

可以减少代码冗余

package cn.bdqn.Dao;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class BaseDao {
	private static String driver="com.mysql.jdbc.Driver";
	private String url="jdbc:mysql://localhost:3306/newsmanagersystem";
	private String user="root";
	private String password="123456";
	protected Connection conn;
	/**
	 * 连接数据库
	 * @return
	 */
	public Connection getConnection(){
			try {
				Class.forName(driver);
				conn=DriverManager.getConnection(url, user, password);
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		return conn;
		
	}
	/**
	 * 关闭数据库
	 */
	public void CloseAll(Connection conn,PreparedStatement pstmt,ResultSet rs){
		if(rs!=null){
			try {
				rs.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		if(pstmt!=null){
			try {
				pstmt.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		if(conn!=null){
			try {
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	}
	/**
	 * 查询操作
	 * @return
	 */
	public ResultSet executeQuery(String sql,Object...params){
		PreparedStatement pstmt=null;
		ResultSet rs=null;
		try {
			pstmt=getConnection().prepareStatement(sql);
			if(params!=null){
				for (int i = 0; i < params.length; i++) {
					pstmt.setObject(i+1, params[i]);
				}
			}
			rs=pstmt.executeQuery();
		} catch (Exception e) {
			e.printStackTrace();
		}finally{
			CloseAll(null, null, null);
		}
		return rs;
	}
	/**
	 * 删，改，插操作
	 * @param sql
	 * @param params
	 * @return
	 */
	 public int executeUpdate(String sql,Object...params){
		 PreparedStatement pstmt=null;
		 int result=0;
		 try {
			pstmt=getConnection().prepareStatement(sql);
			if(params!=null){
				for (int i = 0; i < params.length; i++) {
					pstmt.setObject(i+1, params[i]);
				}
			}
			result=pstmt.executeUpdate();
		} catch (Exception e) {
			e.printStackTrace();
		}finally{
			CloseAll(conn, pstmt, null);
		}
		 return result;
	 }
}