_ UDPClient.java
package com.bill.udp.client;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import com.bill.udp.util.UDPUtils;
public class UDPClient {
private static final String SEND_FILE_PATH = "D:/imgmap.jpg";
public static void main(String[] args){
long startTime = System.currentTimeMillis();
byte[] buf = new byte[UDPUtils.BUFFER_SIZE];
byte[] receiveBuf = new byte[1];
RandomAccessFile accessFile = null;
DatagramPacket dpk = null;
DatagramSocket dsk = null;
int readSize = -1;
try {
accessFile = new RandomAccessFile(SEND_FILE_PATH,"r");
//构造数据报包，用来将长度为 length 的包发送到指定主机上的指定端口号。
dpk = new DatagramPacket(buf, buf.length,new InetSocketAddress(InetAddress.getByName("192.168.1.106"), 5000));
//创建数据报套接字，将其绑定到指定的本地地址。
dsk = new DatagramSocket(5001, InetAddress.getByName("192.168.1.106"));
int sendCount = 0;
while((readSize = accessFile.read(buf,0,buf.length)) != -1){
dpk.setData(buf, 0, readSize);
dsk.send(dpk);
// wait server response
{
while(true){
dpk.setData(receiveBuf, 0, receiveBuf.length);
dsk.receive(dpk);
// confirm server receive
if(!UDPUtils.isEqualsByteArray(UDPUtils.successData,receiveBuf,dpk.getLength())){
System.out.println("resend ...");
dpk.setData(buf, 0, readSize);
dsk.send(dpk);
}else
break;
}
}
System.out.println("send count of "+(++sendCount)+"!");
}
// send exit wait server response
while(true){
System.out.println("client send exit message ....");
dpk.setData(UDPUtils.exitData,0,UDPUtils.exitData.length);
dsk.send(dpk);
dpk.setData(receiveBuf,0,receiveBuf.length);
dsk.receive(dpk);
if(!UDPUtils.isEqualsByteArray(UDPUtils.exitData, receiveBuf, dpk.getLength())){
System.out.println("client Resend exit message ....");
dsk.send(dpk);
}else
break;
}
}catch (Exception e) {
e.printStackTrace();
} finally{
try {
if(accessFile != null)
accessFile.close();
if(dsk != null)
dsk.close();
} catch (IOException e) {
e.printStackTrace();
}
}
long endTime = System.currentTimeMillis();
System.out.println("time:"+(endTime - startTime));
}
}
UDPUtils.java
package com.bill.udp.util;
public class UDPUtils {
private UDPUtils(){}
/** transfer file byte buffer **/
public static final int BUFFER_SIZE = 50 * 1024;
/** controller port **/
public static final int PORT = 50000;
/** mark transfer success **/
public static final byte[] successData = "success data mark".getBytes();
/** mark transfer exit **/
public static final byte[] exitData = "exit data mark".getBytes();
public static void main(String[] args) {
byte[] b = new byte[]{1};
System.out.println(isEqualsByteArray(successData,b));
}
public static boolean isEqualsByteArray(byte[] compareBuf,byte[] buf){
if (buf == null || buf.length == 0)
return false;
boolean flag = true;
if(buf.length == compareBuf.length){
for (int i = 0; i < buf.length; i++) {
if(buf[i] != compareBuf[i]){
flag = false;
break;
}
}
}else
return false;
return flag;
}
public static boolean isEqualsByteArray(byte[] compareBuf,byte[] buf,int len){
if (buf == null || buf.length == 0 || buf.length < len || compareBuf.length < len)
return false;
boolean flag = true;
int innerMinLen = Math.min(compareBuf.length, len);
for (int i = 0; i < innerMinLen; i++) {
if(buf[i] != compareBuf[i]){
flag = false;
break;
}
}
return flag;
}
}
