java nio test

NioTest.java

package com.fuyun.scala;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.nio.charset.Charset;
import java.nio.charset.CharsetDecoder;
import java.nio.charset.CharsetEncoder;
import java.util.Set;

/**
 * Created by fuyun on 2017/4/17.
 * nio test
 */
public class NioTest {
    public static void main(String[] args) throws IOException {
        ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
        serverSocketChannel.bind(new InetSocketAddress(1234));
        serverSocketChannel.configureBlocking(false);
        Selector selector = Selector.open();
        serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);
        CharsetDecoder utf8Decoder = Charset.forName("UTF-8").newDecoder();
        CharsetEncoder utf8Encoder = Charset.forName("UTF-8").newEncoder();
        while (true) {
            int selected = selector.select();
            if (selected <= 0) {
                continue;
            }
            Set<SelectionKey> selectionKeys = selector.selectedKeys();
            for (SelectionKey selectionKey : selectionKeys) {
                if (selectionKey.isAcceptable()) {
                    SocketChannel socketChannel = ((ServerSocketChannel) selectionKey.channel()).accept();
                    socketChannel.configureBlocking(false);
                    ByteBuffer buffer = ByteBuffer.allocate(10);
                    socketChannel.register(selector, SelectionKey.OP_READ, buffer);
                } else if (selectionKey.isReadable()) {
                    SocketChannel socketChannel = (SocketChannel) selectionKey.channel();
                    ByteBuffer buffer = (ByteBuffer) selectionKey.attachment();
                    StringBuilder sb = new StringBuilder();
                    while (socketChannel.read(buffer) >= 1) {
                        buffer.flip();
                        sb.append(utf8Decoder.decode(buffer));
                        buffer.clear();
                    }
                    if (sb.length() > 0) {
                        sb.setLength(sb.length() - 1);
                    }
                    sb.reverse();
                    sb.append("\n");
                    CharBuffer charBuffer = CharBuffer.wrap(sb);
                    ByteBuffer writeBuffer = utf8Encoder.encode(charBuffer);
                    socketChannel.write(writeBuffer);
                }
            }
            selectionKeys.clear();
        }
    }
}

使用nio实现非阻塞服务器