nioutils.java

来自「一个MMORPG手机游戏的服务器端程序源代码」· Java 代码 · 共 133 行

package zsw_mmorpg.common;
import java.nio.*;
import java.nio.channels.*;
import java.io.UnsupportedEncodingException;

/**
 * NIOUtils.java
 *
 * NIO channels
 *
 * @author <a href="mailto:[e-mail]">朱世伟</a>
 * @version 1.0
 */
public class NIOUtils {
    /**
     * 写之前处理下数据包格式
     */
    public static void prepBuffer(GameEvent event, ByteBuffer writeBuffer) {
    // write header
    writeBuffer.clear();
//    writeBuffer.putInt(0);
//    if (event.getGameName() != null)
//        writeBuffer.putInt(event.getGameName().hashCode());
//    else
//    writeBuffer.putInt(0);
    int sizePos = writeBuffer.position();
    writeBuffer.putInt(0);// placeholder for payload size
    // write event
    int payloadSize = event.write(writeBuffer);

    // insert the payload size in the placeholder spot
    writeBuffer.putInt(sizePos, payloadSize);

    // prepare for a channel.write
    writeBuffer.flip();
    }
    /**
     * 往给定通道发送数据
     */
    public static void channelWrite(SocketChannel channel, ByteBuffer writeBuffer) {
        long nbytes = 0;
        long toWrite = writeBuffer.remaining();

        byte[] array = new byte[0];
        int start = 0, end = 0;
        if (writeBuffer.hasArray()) {
            array = writeBuffer.array();
            start = 0;
            end = writeBuffer.limit();
        }
        System.out.println("write array:");     //zsw
        printHexValue(array, start, end);
        // loop on the channel.write() call since it will not necessarily
        // write all bytes in one shot
        try {
            while (nbytes != toWrite) {
                nbytes += channel.write(writeBuffer);
                try {
                    Thread.sleep(Globals.CHANNEL_WRITE_SLEEP);
                }
                catch (InterruptedException e) {
                }
            }
        }
        catch (ClosedChannelException cce) {
        }
        catch (Exception e) {
        }

        // get ready for another write if needed
        writeBuffer.rewind();
    }
    /**
     * write a String to a ByteBuffer, 
     * prepended with a short integer representing the length of the String
     */
    public static void putStr(ByteBuffer buff, String str) {
    if (str == null) {
        buff.putShort((short)0);
    }
    else {
        try {
            byte[] strData = str.getBytes("UTF-8");
            buff.putShort((short)strData.length);
            buff.put(strData);
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        }
    }
    }
    /**
     * read a String from a ByteBuffer 
     * that was written w/the putStr method
     */
    public static String getStr(ByteBuffer buff) {
    short len = buff.getShort();
    if (len == 0) {
        return null;
    }
    else {
        byte[] b = new byte[len];
        buff.get(b);
        String result = null;
        try {
            result = new String(b,"UTF-8" );
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        }
        return result;

    }
    }
    /**16进制,打印byte数组*/
    public static void   printHexValue(byte[] data, int start, int end) {
         int value = 0;
         String hexStr = "";
         String result = "";

         result += "\"";
         for (int i = start; i < end; i++) {
             value = data[i] & 0xff;
             hexStr = Integer.toHexString(value);
             if (hexStr.length() < 2) {
                 hexStr = "0" + hexStr;
             }
             result += hexStr + " ";
            }
            result += "\"";

            System.out.println(result);
        }
}