connectionfactory.java

jsf实现的示例

package cn.handson.util;

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

public abstract class ConnectionFactory {
	
	static Connection con;
	PreparedStatement pstmt=null;
	ResultSet rs=null;
	
	private Connection getConnection(){
		if(con==null){
			con=createConnection();
		}
		return con;
	}
	
	private Connection createConnection(){
		try{
			Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
		}catch(ClassNotFoundException e){
			e.printStackTrace();
			return null;
		}
		String url="jdbc:microsoft:sqlserver://localhost:1433;databasename=Test";
		try{
			con=DriverManager.getConnection(url,"sa","sa");
		}catch(SQLException e){
			e.printStackTrace();
		}		
		return con;
	}
	
	public ResultSet executeQuery(String sql) throws SQLException{
		System.out.println(sql);
		pstmt=getConnection().prepareStatement(sql);
		rs=pstmt.executeQuery();
		return rs;
	}
	
	public int executeUpdate(String sql) throws SQLException{
		int i=-1;
		System.out.println(sql);
		pstmt=getConnection().prepareStatement(sql);
		i=pstmt.executeUpdate();
		return i;
	}
	
	public void closeCon() throws SQLException{
		pstmt.close();
		con.close();
		con=null;
	}
	
	public void closeCon(ResultSet rs) throws SQLException{
		rs.close();
		pstmt.close();
		con.close();
		con=null;
	}

}