socket异常

Question

String connectRequest = "Request: CON USER "
+ name.getText() + " PASS "
+ psw.getText();
request(connectRequest);
System.out.println(client+"$$$$$$$$$$$$$$$");
String response=getResponse().toString();

/**
* 获取服务器端的响应信息..
*
* @param sock
* @return
*/
private StringBuffer getResponse() {
StringBuffer buffer = new StringBuffer();
InputStream in=null;
//在这时socket就已经关了

try {
in = client.getInputStream();
byte[] buf = new byte[8192];
int len = 0;

        while ((len = in.read(buf)) != -1) {

            buffer.append(new String(buf, 0, len));
            if(len<=8192){
                break;
            }
        }
    } catch (IOException e) {
        System.out.println("exception in getResponse.");
        e.printStackTrace();
    }finally{
        close(in);
    }
    System.out.println(buffer.toString()+"----");

    return buffer;
}


/**
 * 向服务器端发出请求
 * 
 * @param socket
 * @param str
 *            客户端请求命令
 */
private void request( String str) {

    OutputStream out=null;
    try {
        out = client.getOutputStream();
        byte[] buffer = str.getBytes();
        int len = buffer.length;
        out.write(buffer, 0, len);
        System.out.println(str + " send.");

    } catch (IOException e) {
        System.out
                .println("client socket get output stream failed. request");
        e.printStackTrace();
    }finally{
        close(out);
    }
}

我在做一个FTP协议应用的程序，client是Socket全局变量。不过当request方法调用完了，再调用getResponse()方法是发生socket异常，说socket is closed。请哪位大侠给解决下 ！！！！！！

Answer 1

Java里面是传引用的，这点你首先要明确
你out = client.getOutputStream();
这里，你是得到了client的一个outPutStream的引用
你finally中，把他关了，整个socket当然就被关了。
写方法不能这么写的
这样
[code="java"]
private void request( String str,Socket client)
或者是 private void request( String str,OutPutStream out)
[/code]