我們定義發送者和接收者，發送者作為客戶端，接收者作為服務端。
Sender.java
import?java.io.DataOutputStream;
import?java.io.IOException;
import?java.net.Socket;
import?java.util.Arrays;
public?class?Sender?{
public?static?void?main(String[]?args)?throws?Exception?{
//?127.0.0.1?代表本機地址，在?8888?端口上監聽
Sender?sender?=?new?Sender("127.0.0.1",?8888);
byte[]?bytes?=?{15,?16,?17,?120};?//?對應的十六進制是?0F?10?11?78
sender.send(bytes);
System.out.println("發送"?+?Arrays.toString(bytes)?+?"完畢！");
}
private?final?String?host;
private?final?int?port;
public?Sender(String?host,?int?port)?{
this.host?=?host;
this.port?=?port;
}
private?void?send(byte[]?bytes)?throws?IOException?{
Socket?socket?=?new?Socket(host,?port);?//?建立和服務端的?socket
try?(DataOutputStream?dos?//?建立輸出流
=?new?DataOutputStream(socket.getOutputStream()))?{
dos.write(bytes,?0,?bytes.length);?//?向輸出流寫入?bytes
}
}
}
Receiver.java
import?java.io.DataInputStream;
import?java.io.IOException;
import?java.net.ServerSocket;
import?java.net.Socket;
public?class?Receiver?{
public?static?void?main(String[]?args)?throws?Exception?{
Receiver?receiver?=?new?Receiver(8888);
receiver.receive();
}
private?final?ServerSocket?serverSocket;
public?Receiver(int?port)?throws?IOException?{
serverSocket?=?new?ServerSocket(port);
}
private?void?receive()?throws?IOException?{
System.out.println("等待客戶端連接...");
Socket?socket?=?serverSocket.accept();
try?(DataInputStream?dis?=?new?DataInputStream(socket.getInputStream()))?{
byte[]?bytes?=?new?byte[1024];?//?假設發送的字節數不超過?1024?個
int?size?=?dis.read(bytes);?//?size?是讀取到的字節數
String?hex?=?bytesToHex(bytes,?0,?size);
System.out.println("接收到的byte數組的十六進制："?+?hex);
}
}
/**
?*?將?byte?數組轉化為十六進制字符串
?*
?*?@param?bytes?byte[]?數組
?*?@param?begin?起始位置
?*?@param?end?結束位置
?*?@return?byte?數組的十六進制字符串表示
?*/
private?String?bytesToHex(byte[]?bytes,?int?begin,?int?end)?{
StringBuilder?hexBuilder?=?new?StringBuilder(2?*?(end?-?begin));
for?(int?i?=?begin;?i?<?end;?i++)?{
hexBuilder.append(Character.forDigit((bytes[i]?&?0xF0)?>>?4,?16));?//?轉化高四位
hexBuilder.append(Character.forDigit((bytes[i]?&?0x0F),?16));?//?轉化低四位
hexBuilder.append('?');?//?加壹個空格將每個字節分隔開
}
return?hexBuilder.toString().toUpperCase();
}
}
運行，首先啟動服務端：
然後啟動客戶端：
查看接收結果：