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UDP2_传一个long类型的数
TestUDPServer.java
class="java">import java.net.*;
import java.io.*;
public class TestUDPServer
{
	public static void main(String args[]) throws Exception
	{
		byte buf[] = new byte[1024];
		DatagramPacket dp = new DatagramPacket(buf, buf.length);
		//UDP的5678端口
		DatagramSocket ds = new DatagramSocket(5678);
		while(true)
		{
			ds.receive(dp);
			//打印字符
			//System.out.println(new String(buf,0,dp.getLength()));
			
			ByteArrayInputStream bais = new ByteArrayInputStream(buf);
			DataInputStream dis = new DataInputStream(bais);
			System.out.println(dis.readLong());
		
		}
	}
}
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F:\java\socket>javac TestUDPServer.java F:\java\socket>java TestUDPServer 10000
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TestUDPClient.java
import java.net.*;
import java.io.*;
public class TestUDPClient
{
	public static void main(String args[]) throws Exception
	{
		//定义一个long类型的数
		long n = 10000L;
		//字节数组
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		DataOutputStream dos = new DataOutputStream(baos);
		//将n写入字节数组
		dos.writeLong(n);
		
		byte[] buf = baos.toByteArray();
		System.out.println(buf.length);
		
		//byte[] buf = (new String("Hello")).getBytes();
		DatagramPacket dp = new DatagramPacket(buf, buf.length, 
											   new InetSocketAddress("127.0.0.1", 5678)
											   );
		DatagramSocket ds = new DatagramSocket(9999);
		ds.send(dp);
		ds.close();
		
		
	}
}
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f:\java\socket>javac TestUDPClient.java f:\java\socket>java TestUDPClient 8 f:\java\socket>
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