java socket总是连接不上

[guoxiaoxi32]

我自己开发了一个socketservicer和socketClient。但是客户端有的时候连接的上有的时候连不上。连不上的时候总是出现这样的两种错误：
（1）：
com.enterprisedt.net.ftp.ControlChannelIOException: Connection reset
at com.enterprisedt.net.ftp.FTPControlSocket.readLine(FTPControlSocket.java:1029)
at com.enterprisedt.net.ftp.FTPControlSocket.readReply(FTPControlSocket.java:1064)
at com.enterprisedt.net.ftp.FTPControlSocket.sendCommand(FTPControlSocket.java:988)
at com.enterprisedt.net.ftp.FTPClient.quit(FTPClient.java:4044)
at com.enterprisedt.net.ftp.FileTransferClient.disconnect(FileTransferClient.java:1034)
at Tools.FTP.edtftpj.uploadFile(edtftpj.java:26)
at main.main$MyThread.run(main.java:225)
………………
………………
（2）：
java.net.ConnectException: Connection timed out: connect
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(Unknown Source)
at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at Tools.Scoket.Scoket.CreatScoket(Scoket.java:19)
at main.main$MyThread.run(main.java:233)
at org.eclipse.swt.widgets.Synchronizer.syncExec(Synchronizer.java:178)
at org.eclipse.swt.widgets.Display.syncExec(Display.java:4251)
at main.main$3.widgetSelected(main.java:178)
at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:228)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1003)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3823)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3422)
at main.main.main(main.java:192)

我总是找不到解决方法。求大家帮助，在线给分。。。

[meZhou]

在while循环中创建了过多了connection 没有及时的关闭 一般情况当创建了又没有关闭的connection达到400-500左右的时候就会有这个报错了 我把创建connection的那几句隐去之后
没有代码，所以网上找的
http://tieba.baidu.com/f?kz=604910306

[madFatso]

你至少贴点报错时的代码吧

[guoxiaoxi32]

public void CreatScoket(String serviceIp,int servicePort,Text text) throws InterruptedException{
try {
String ipAdd = serviceIp;
int port = servicePort;
Socket s = new Socket(ipAdd,port);
String time = "";
TimeUtil timeUtil = new TimeUtil();
time = "和讯机构投资"+timeUtil.getString(3);
//发送服务器指令
BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(s.getOutputStream()));
bw.write(time);
System.out.println(time);
bw.flush();
//接受服务器指令
BufferedReader br = new BufferedReader(new InputStreamReader(s.getInputStream()));
String str = br.readLine();
while(str.length()==0){
Thread.sleep(1000);
br = new BufferedReader(new InputStreamReader(s.getInputStream()));
str = br.readLine();
}
System.out.println("服务器："+str);
bw.close();
br.close();


} catch (UnknownHostException e1) {
// TODO Auto-generated catch block
System.out.println("服务器连接失败！");
e1.printStackTrace();
} catch (IOException e1) {
// TODO Auto-generated catch block
System.out.println("服务器连接失败!!!");
e1.printStackTrace();
}
}

[guoxiaoxi32]

java.net.ConnectException: Connection refused: connect

[qybao]

Socket没close，再进入方法是，端口已经被占用了吧

[qingbt]

接收端用readline的话，写入端必须手工加"\n"

[yl_zxy_ccssddnn_net]

[Quote=引用 4 楼 guoxiaoxi32 的回复:]
java.net.ConnectException: Connection refused: connect
[/Quote]
这种情况一般是服务器端的原因，要么是服务器端没有启动，或者说是防火墙处于启开状态！
楼主上面的贴出的代码感觉有些混乱，建议对代码重新进行封装，针对客户端的代码我习惯按下面的方式编写：

package com.ncs.client;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.Socket;

public class Client {
	private String host;
	private int port;
	
	private Socket client;

	public Client(String host, int port) {
		this.host = host;
		this.port = port;
	}
	
	/**
	 * 与服务端建立连接
	 * @throws Exception
	 */
	public void connect() throws Exception {
		client = new Socket();
		client.connect(new InetSocketAddress(host, port));
	}
	
	/**
	 * 与设备建立连接
	 * @param timeout 超时时间
	 * @throws Exception
	 */
	public void connect(int timeout) throws Exception {
		client = new Socket();
		client.setSoTimeout(timeout);
		client.connect(new InetSocketAddress(host, port));
	}
	
	/**
	 * 服务向服务器端发送数据
	 * @throws Exception
	 */
	public void send() throws Exception {
		//do some thing
	}
	
	/**
	 * 服务接受服务端的数据
	 * 这个最好是客户端和服务端都协商好，用一个特殊符号作为结束标记。
	 * 不然无法知晓服务器端的数据是否发送结束。
	 * @return
	 * @throws Exception
	 */
	public byte[] receive() throws Exception {
		//do some thing
		return null;
	}
	
	public void close() {
		try {
			client.close();
		} catch (IOException e) {}
		client = null;
	}
}

[roclostr1987]

//接受服务器指令
BufferedReader br = new BufferedReader(new InputStreamReader(s.getInputStream()));
String str = br.readLine();
while(str.length()==0){
Thread.sleep(1000);
br = new BufferedReader(new InputStreamReader(s.getInputStream()));
str = br.readLine();
}
System.out.println("服务器："+str);

你这段代码怎么写的这么诡异啊？
为什么要反复的去new BufferedReader呢？难道是等待服务端返回字符吗？
如果你使用BufferedReader是不需要等待的，因为代码走到readLine会自己等待流的。