jdbc

package com.yum.amp.util;

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


public class DBUtil {
	//private Connection conn;
	private static final String DRIVER = "net.sourceforge.jtds.jdbc.Driver";
	private static final String URL = "jdbc:jtds:sqlserver://127.0.0.1:1433/test";
	private static final String USERNAME = "sa";
	private static final String PASSWORD = "123456";
	
//	public DBUtil() {
//		try{
//			//加载驱动
//			Class.forName(DRIVER);
//			//连接数据库
//			this.conn = DriverManager.getConnection(URL, USERNAME, PASSWORD);
//		} catch(ClassNotFoundException cnfe) {
//			cnfe.printStackTrace();
//		} catch(SQLException e) {
//			e.printStackTrace();
//		}
//	}
//
//	private Statement getStatement() {
//		Statement stmt = null;
//		try {
//			stmt = conn.createStatement();
//		} catch (SQLException e) {
//			e.printStackTrace();
//		}
//		return stmt;
//	}
//	
//	private PreparedStatement getPreparedStatement(String sql) {
//		PreparedStatement pstmt = null;
//		try {
//			pstmt = conn.prepareStatement(sql);
//		} catch (SQLException e) {
//			e.printStackTrace();
//		}
//		return pstmt;
//	}
	
	static {
		try {
			//加载数据库驱动
			Class.forName(DRIVER);
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
	}
	
	
	//获取数据库连接对象
	public static Connection getConn() {
		Connection conn = null;
		try {
			//"jdbc:oracle:thin:@localhost:1521:你的数据库名字", "用户名","密码"
			conn = DriverManager.getConnection(URL, USERNAME,PASSWORD);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return conn;
	}
	
	
	//获取语句执行对象
	public static Statement getStatement(Connection conn) {
		Statement stmt = null;
		try {
			stmt = conn.createStatement();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return stmt;
	}

	//获取预处理语句执行对象
	public static PreparedStatement getPreparedStatement(Connection conn,String sql) {
		PreparedStatement pstmt = null;
		try {
			pstmt = conn.prepareStatement(sql);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return pstmt;
	}
	
	//获取结果集对象
	public static ResultSet getResultSet(PreparedStatement pstmt) {
		ResultSet res = null;
		try {
			res = pstmt.executeQuery();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return res;
	}

	//获取结果集对象
	public static ResultSet getResultSet(Statement stmt, String sql) {
		ResultSet res = null;
		try {
			res = stmt.executeQuery(sql);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return res;
	}


	
	//关闭资源方法
	public static void close(Connection conn, Statement stmt, ResultSet res) {
		close(res);
		close(stmt);
		close(conn);
	}

	//封装方法关闭语句对象
	private static void close(Statement stmt) {
		if (stmt != null) {
			try {
				stmt.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
			stmt = null;
		}
	}

	//封装方法关闭结果集对象
	private static void close(ResultSet res) {
		if (res != null) {
			try {
				res.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
			res = null;
		}
	}

	//封装方法关闭数据库连接对象
	private static void close(Connection conn) {
		try {
			if (conn != null && !conn.isClosed()) {
				conn.close();
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
		conn = null;
	}
}