Question

java socket问题，写了个简单的程序，客户端输出到服务器端，服务器端接收到后返回数据，出现问题！！

server端：
ServerSocket ss = null;
Socket socket = null;
try {
ss=new ServerSocket(8888);
System.out.println("server is starting");
socket=ss.accept();
BufferedReader br=new BufferedReader(
new InputStreamReader(socket.getInputStream()));
BufferedWriter bw=new BufferedWriter(
new OutputStreamWriter(socket.getOutputStream()));

System.out.println(br.readLine());
bw.write(br.readLine()+"received");
br.close();
bw.close();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
socket.close();
ss.close();
} catch (IOException e) {
e.printStackTrace();
}
}

client端：
Socket socket = null;
try {
socket=new Socket("127.0.0.1",8888);
OutputStream os=socket.getOutputStream();
InputStream is=socket.getInputStream();
BufferedWriter bw=new BufferedWriter(new OutputStreamWriter(os));
BufferedReader br=new BufferedReader(new InputStreamReader(is));

bw.write("hello");
System.out.println(br.readLine());
bw.close();
br.close();
} catch (IOException e) {
e.printStackTrace();
} finally {
if(socket!=null) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
客户端的数据传不到服务器端，服务器端的数据不能返回到客户端

Answer 1

我修改了，直接用socket的输入输出流实现：
服务器端：
import java.io.*;
import java.net.*;
public class server{

public static void main(String args[]) throws IOException
{
ServerSocket ss = null;
Socket socket = null;
try {
ss=new ServerSocket(8888);
System.out.println("server is starting");
socket=ss.accept();
System.out.println("New connection accepted " +socket.getInetAddress() + ":" +socket.getPort());
InputStream Is = socket.getInputStream();
OutputStream Os = socket.getOutputStream();
DataInputStream DIS = new DataInputStream(Is);
PrintStream PS = new PrintStream(Os);
String recvStr = DIS.readLine();
System.out.println(recvStr);
PS.println(recvStr+"received");
DIS.close();
PS.close();
Is.close();
Os.close();

} catch (IOException e) {
e.printStackTrace();
} finally {
try {
socket.close();
ss.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
客户端：
import java.io.*;
import java.net.*;
public class client{

public static void main(String args[]) throws IOException
{
Socket socket = null;
try {
socket=new Socket("127.0.0.1",8888);
if(socket == null)
System.out.println("error");
InputStream Is = socket.getInputStream();
OutputStream Os = socket.getOutputStream();
DataInputStream DIS = new DataInputStream(Is);
PrintStream PS = new PrintStream(Os);
PS.println("hello");
System.out.println(DIS.readLine());
DIS.close();
PS.close();
Is.close();
Os.close();
} catch (IOException e) {
e.printStackTrace();
} finally {
if(socket!=null) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}

运行结果：
java server
server is starting
New connection accepted /127.0.0.1:45786
hello

java client
helloreceived

追问

这样写我这儿也没问题，问题是这个类得readline是过期的啊，我要读一行数据还是不太方便~~~

Answer 2

嗯，问题处在了楼主没有调用bw.flush()方法，数据还都在内存里呢还没写到流中，当然看不到了，应该在server和client的bw.close()上面各加bw.flush()就Ok了

追问

flush都加过了，还是不行，如果单独在client端写，在server端读，完全没有问题，但是在两端同时写和读就有问题