conn.java

基于Java实现的聊天室功能

package liuyan;

import java.sql.*;
public class Conn {
	private static Connection conn;
	private Statement  stmt;
	private ResultSet rs;
	private static final String drivername ="com.microsoft.jdbc.sqlserver.SQLServerDriver";
	private static final String url = "jdbc:microsoft:sqlserver://127.0.0.1:1433;DatabaseName=liuyan";

        public Conn(){}
        
        public static synchronized Connection getCon(){
        	try{
        		Class.forName(drivername).newInstance();
        		conn = DriverManager.getConnection(url,"sa","123456789");
        	return conn;
        	}catch(Exception e){
        		e.printStackTrace();
        		return null;
        	}
        }
        
        public Statement getStmt(){
        	try{
        		conn = getCon();
        		stmt = conn.createStatement();
        		return stmt;
        	}catch(Exception e){
        		return null;
        	}
        }
        
        public synchronized void close(){
        	try{
        		if(rs!=null){
        			rs.close();
        			rs = null;
        		}
        	}catch(Exception e){
        		
        	}
        	try{
        		if(stmt!=null){
        			stmt.close();
        			stmt = null;
        		}
        	}catch(Exception e){
        		
        	}
        	try{
        		if(conn!=null){
        			conn.close();
        			conn = null;
        		}
        	}catch(Exception e){
        		
        	}
        	System.out.println("close success!!");
        }
}