將MAC地址字節數組格式化爲字符串

Question

我正在使用此代碼來查找計算機的MAC地址。此代碼直接打印MAC地址，但我想將其作爲字符串返回。我完全困惑。

請大家幫忙。

try { 

    InetAddress add = InetAddress.getByName("10.123.96.102"); 
    NetworkInterface ni1 = NetworkInterface.getByInetAddress(add); 
    if (ni1 != null) { 
     byte[] mac1 = ni1.getHardwareAddress(); 
     if (mac1 != null) { 
      for (int k = 0; k < mac1.length; k++) { 
       System.out.format("%02X%s", mac1[k], (k < mac1.length - 1) ? "-" : ""); 
      } 
     } else { 
      System.out.println("Address doesn't exist "); 
     } 
     System.out.println(); 
    } else { 
     System.out.println("address is not found."); 
    } 
} catch (UnknownHostException e) { 
    e.printStackTrace(); 
} catch (SocketException e) { 
    e.printStackTrace(); 
} 

Answer 1

Mac地址沒有標準文本表示。您只需要將其轉換爲十六進制，並將字節分隔以提高可讀性。下面是我在使用ifconfig的Unix上的格式使用你只需要改變的功能，

public static String getMacAddress(String ipAddr) 
     throws UnknownHostException, SocketException { 
    InetAddress addr = InetAddress.getByName(ipAddr); 
    NetworkInterface ni = NetworkInterface.getByInetAddress(addr); 
    if (ni == null) 
     return null; 

    byte[] mac = ni.getHardwareAddress(); 
    if (mac == null) 
     return null; 

    StringBuilder sb = new StringBuilder(18); 
    for (byte b : mac) { 
     if (sb.length() > 0) 
      sb.append(':'); 
     sb.append(String.format("%02x", b)); 
    } 
    return sb.toString(); 
} 

「：」到「 - 」。

Answer 2

也許你可以使用公共編解碼器的Hex.encodeHex(bytes)。

Here are其他方式來做到這一點，沒有第三方庫。

Answer 3

private static final byte[] NULL_MAC = new byte[] {0, 0, 0, 0, 0, 0}; 

    public static String getMacString(byte[] macAddress) { 
    StringBuilder retval = new StringBuilder(17); 
    if (macAddress == null) { 
     macAddress = NULL_MAC; 
    } 
    boolean isFirst = true; 
    for (byte b : macAddress) { 
     if (!isFirst) { 
     retval.append(":"); 
     } else { 
     isFirst = false; 
     } 
     retval.append(String.format("%02x", b & 0xff)); 
    } 
    return retval.toString(); 
    } 

Answer 4

它應該是這樣的

StringBuilder sb = new StringBuilder(); 
for (int i = 0; i < mac.length(); i++) { 
    b.append(String.format("%02X%s", mac[i], (i < mac.length() - 1) ? "-" : ""); 

String s = sb.toString(); 

Answer 5

String s=""; 
for (int i = 0; i < mac.length; i++) { 
    s += String.format("%02X%s", mac[i], (i < mac.length - 1) ? "-" : ""); 
} 

Answer 6

通過這一點，你可以很容易地甲的Mac地址字符串。從這裏

import java.net.InetAddress; 
import java.net.NetworkInterface; 
import java.net.SocketException; 
import java.net.UnknownHostException; 

public class App{ 

    public static void main(String[] args){ 

    InetAddress ip; 
    try { 

     ip = InetAddress.getLocalHost(); 
     System.out.println("Current IP address : " + ip.getHostAddress()); 

     NetworkInterface network = NetworkInterface.getByInetAddress(ip); 

     byte[] mac = network.getHardwareAddress(); 

     System.out.print("Current MAC address : "); 

     StringBuilder sb = new StringBuilder(); 
     for (int i = 0; i < mac.length; i++) { 
      sb.append(String.format("%02X%s", mac[i], (i < mac.length - 1) ? "-" : ""));   
     } 
     System.out.println(sb.toString()); 

    } catch (UnknownHostException e) { 

     e.printStackTrace(); 

    } catch (SocketException e){ 

     e.printStackTrace(); 

    } 

    } 

} 

副本：http://www.mkyong.com/java/how-to-get-mac-address-in-java/comment-page-1/#comment-139182

Answer 7

我知道這是一個Java相關的問題，但對於誰在這裏結束了像我一樣的Scala用戶，這是一個辦法做到這一點在斯卡拉：

bytes.map("%02X" format _).mkString (":")