TCP 简单通信作业 小白求助大佬

[呵呵小哥]

编辑tcp的循环聊天一直出问题，希望大佬帮忙给看一下，万分感谢！
以下为代码：


服务端：
public class TCPServer {
public static void main(String[] args) {
ServerSocket ss = null;
Socket s = null;
BufferedReader br = null;
try {
ss = new ServerSocket(20000);
s = ss.accept();
InputStream in = s.getInputStream();
br = new BufferedReader(new InputStreamReader(in));
String line = null;
InetAddress ia = s.getInetAddress();
while((line = br.readLine()) != null){
System.out.println(ia.getHostAddress() + "接受到了:" + line);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if(br != null){
br.close();
}
if(s != null){
s.close();
}
if(ss != null){
ss.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}


以下是客户端：

public class TCPClient {
public static void main(String[] args) {
Socket s = null;
BufferedWriter bw = null;
BufferedReader br = null;
try {
s = new Socket("192.168.2.105", 20000);
OutputStream out = s.getOutputStream();
bw = new BufferedWriter(new OutputStreamWriter(out));
br = new BufferedReader(new InputStreamReader(System.in));
String line = null;
while((line = br.readLine()) != null){
bw.write(line);
bw.flush();
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if(br != null){
br.close();
}
if(bw != null){
bw.close();
}
if(s != null){
s.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}

}


最后运行，服务端收到的一直是空白，，，
谢谢大佬了！！！

[一克李普斯]

客户端加上 pw = printWriter(bw,true)；

[呵呵小哥]

引用 1 楼 老学徒的回复:

客户端加上 pw = printWriter(bw,true)；

不行啊，打上了还是空白的

[三月の狮子]

line的值是null?

[Dan淡淡的心]

首先确定一下 client 是否在读取数据 在循环内打印一下line 可以打印的话 单机测试一下 将 ip改为 127.0.0.1

[qq_39936465]

引用 楼主 永以为依也 的回复:

编辑tcp的循环聊天一直出问题，希望大佬帮忙给看一下，万分感谢！
以下为代码：


服务端：
public class TCPServer {
public static void main(String[] args) {
ServerSocket ss = null;
Socket s = null;
BufferedReader br = null;
try {
ss = new ServerSocket(20000);
s = ss.accept();
InputStream in = s.getInputStream();
br = new BufferedReader(new InputStreamReader(in));
String line = null;
InetAddress ia = s.getInetAddress();
while((line = br.readLine()) != null){
System.out.println(ia.getHostAddress() + "接受到了:" + line);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if(br != null){
br.close();
}
if(s != null){
s.close();
}
if(ss != null){
ss.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}


以下是客户端：

public class TCPClient {
public static void main(String[] args) {
Socket s = null;
BufferedWriter bw = null;
BufferedReader br = null;
try {
s = new Socket("192.168.2.105", 20000);
OutputStream out = s.getOutputStream();
bw = new BufferedWriter(new OutputStreamWriter(out));
br = new BufferedReader(new InputStreamReader(System.in));
String line = null;
while((line = br.readLine()) != null){
bw.write(line);
bw.flush();
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if(br != null){
br.close();
}
if(bw != null){
bw.close();
}
if(s != null){
s.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}

}


最后运行，服务端收到的一直是空白，，，
谢谢大佬了！！！

因为你客户端BufferedWrite 流一直没关闭，所以服务器一直处于等待中，这里flush不起效果。

while ((line = br.readLine()) != null) {
				bw.write(line);
				bw.close();
			}

直接在while中关闭就行了。
要循环对话的话，服务器端也需要添加while循环。自己再改一下吧。

[qq_39936465]

我看了元程序应该是下面有问题，if条件是无法满足的，只要br关闭后跟着关闭bw即可。

if(bw != null){
bw.close();
}

[qq_39936465]

建议服务器和客户端之间对话用PrintStream流，这样client可以改一下

public class TCPClient {
	public static void main(String[] args) {
		Socket s = null;
		PrintStream ps=null;
		BufferedReader br = null;
		try {
			s = new Socket("localhost", 20000);
			OutputStream out = s.getOutputStream();
			ps = new PrintStream(out);
			br = new BufferedReader(new InputStreamReader(System.in));
			String line = null;
			while ((line = br.readLine()) != null) {
				ps.println(line);
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
				if (br != null) {
					br.close();
					s.close();
				}
			} catch (IOException e) {
				e.printStackTrace();
			}
		}

	}
}

用loaclhost测试没有问题。

[qq_39936465]

用BufferedWriter需要添加一句newLine(), 用printstream更灵活方便点。client 按下面改一下就行了 while((line = br.readLine()) != null){ bw.write(line); bw.newLine(); bw.flush(); }