使用java中的非阻塞I / O发送消息（NIO API）(Sending message using non-blocking I/O in java(NIO API))

 我正在编写客户端向服务器发送文本消息的服务器/客户端程序。我使用了非阻塞I / O（NIO API），但服务器上的消息无法正确显示。这是我在服务器上的代码： 
 
private JTextArea displayArea;
private int numBytes;
private ByteBuffer buffer;
/*...
some code is here
...*/
displayArea = new JTextArea();
add(new JScrollPane(displayArea), BorderLayout.CENTER);
setSize(400, 500);
setVisible(true);
/*...
some code is here
...*/
buffer = ByteBuffer.allocate(20);
buffer.clear();
displayArea.append("reading data...");
do{
   numBytes = socketChannel.read(buffer);
}while(numBytes == -1);
displayArea.append("\nData read.");
buffer.flip();
int usedBytes = buffer.position();
byte[] bufferArray = buffer.array();
String message = new String(bufferArray, 0, usedBytes);
displayArea.append("\n"+message);
 
 这是一段客户端代码： 
 
byte[] byteData = message.getBytes();
buffer.put(byteData);
socketChannel.write(buffer);
buffer.clear();
 
 在客户端向服务器发送消息的运行时，显示空格字符或一条消息。 

I'm writing a server/client program that clients send text message to server.I have used non-blocking I/O (NIO API) but messages on the server do not display correctly.this is my code on server:
 
private JTextArea displayArea;
private int numBytes;
private ByteBuffer buffer;
/*...
some code is here
...*/
displayArea = new JTextArea();
add(new JScrollPane(displayArea), BorderLayout.CENTER);
setSize(400, 500);
setVisible(true);
/*...
some code is here
...*/
buffer = ByteBuffer.allocate(20);
buffer.clear();
displayArea.append("reading data...");
do{
   numBytes = socketChannel.read(buffer);
}while(numBytes == -1);
displayArea.append("\nData read.");
buffer.flip();
int usedBytes = buffer.position();
byte[] bufferArray = buffer.array();
String message = new String(bufferArray, 0, usedBytes);
displayArea.append("\n"+message);
 
And this is a piece of client code:
 
byte[] byteData = message.getBytes();
buffer.put(byteData);
socketChannel.write(buffer);
buffer.clear();
 
In run time when a client send message to server , space characters or a piece of message is shown.

原文：https://stackoverflow.com/questions/26072926