DB .java

package com.zf.util;

import java.sql.*;
public class DB {
	private static final String DRIVER="oracle.jdbc.driver.OracleDriver";
	private static final String strURL="jdbc:oracle:thin:@localhost:1521:oracle9i";
	private static final String username="system";
	private static final String password="system";

	public static Connection getConn(){
		Connection connection;
		try {
			Class.forName(DRIVER);
			connection =DriverManager.getConnection(strURL,username,password);
		} catch (ClassNotFoundException e) {
			System.out.println("驱动连接失败!");			
			e.printStackTrace();
			return null;
		} catch (SQLException e) {
			System.out.println("数据库连接失败!");
			e.printStackTrace();
			return null;
		}
		return connection;	
	}
	public static PreparedStatement getPstmt(Connection conn,String sql) throws Exception {
		PreparedStatement pstmt = conn.prepareStatement(sql);
		return pstmt;
	}
	public static Statement getStatement(Connection conn)throws SQLException {
		Statement stmt = null; 		
		if(conn != null) {
			stmt = conn.createStatement();
		}		
		return stmt;
	}
	public static ResultSet getResultSet(Statement stmt, String sql)throws SQLException {
		ResultSet rs = null;		
		if(stmt != null) {
			rs = stmt.executeQuery(sql);
		}
		return rs;
	}	
//	关闭连接
	public static void closeConn(Connection conn){
		try {
			if(conn!=null){
				conn.close();
				conn=null;
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	public static void closePstmt(PreparedStatement pstmt){
		try {
			if(pstmt!=null){
				pstmt.close();
				pstmt=null;
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	public static void closeStmt(Statement stmt){

		try {
			if(stmt!=null){
				stmt.close();
				stmt=null;
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}		
	}
	public static void colseRs(ResultSet rs){
		try {
			if(rs!=null){
				rs.close();
				rs=null;
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}	
	}	
	public static void main(String[] args){
		new DB().getConn();
		
	} 
}