utilize NetworkInterface Get server MAC address    A lot of times , We need to get the server hardware information ( such as MAC address ), There are several common ways :
*   Using command line program to get hard disk information , And then through the Runtime.getRuntime().exec Get output stream , Then through string analysis MAC address
* Compiling local programs , And then through the JNI call    The above two methods need to distinguish different operating system platforms , Separate coding , It's troublesome , such as
*  windows The platform needs to be used iptables /all command
* linux The platform needs to be used ifconfig command     
  This paper introduces a general cross platform operation mode , That's it JDK Self contained NetworkInterface Interface , The interface is in the JDK1.4 It's already there , But it has less functions ,JDK1.6 Since then, many new functions have been added , Pretty good .
       Specific functions you can refer to API file , Here's how to get the server MAC address , The code is as follows , There are notes , Not much . // Get all network card's MAC address public
static List<String> getAllMac() { List<String> list = new ArrayList<String>();
try { Enumeration<NetworkInterface> e =
NetworkInterface.getNetworkInterfaces();// Returns an enumerated instance of all network interfaces while
(e.hasMoreElements()) { NetworkInterface network = e.nextElement();// Get current network interface
if (network != null) { if (network.getHardwareAddress() != null) { // get MAC address
// The result is a byte array , Each item is a byte, We need to pass parseByte Method to a common hexadecimal representation byte[] addres =
network.getHardwareAddress(); StringBuffer sb = new StringBuffer(); if (addres
!= null && addres.length > 1) {
sb.append(parseByte(addres[0])).append(":").append(
parseByte(addres[1])).append(":").append(
parseByte(addres[2])).append(":").append(
parseByte(addres[3])).append(":").append(
parseByte(addres[4])).append(":").append( parseByte(addres[5]));
list.add(sb.toString()); } } } else { System.out.println(" obtain MAC Address exception "); } } }
catch (SocketException e) { e.printStackTrace(); } return list; } // Format binary
private static String parseByte(byte b) { int intValue = 0; if (b >= 0) {
intValue = b; } else { intValue = 256 + b; } return
Integer.toHexString(intValue); }  then , We use the following test code , Take a look at the test results List<String> list =
getAllMac(); for (String mac : list) { System.out.println(mac); }  The output results are as follows :
0:18:8b:cc:xx:e3 0:0:0:0:0:0:0:e0 0:50:xx:c0:0:1 0:50:xx:c0:0:8 
You found out ,"0:18:8b:cc:xx:e3", only one 0, It looks very awkward , We might as well revise it parseByte method , as follows : private static
String parseByte(byte b) { String s = "00"+Integer.toHexString(byte0); return
s.substring(s.length() - 2); }  The output changes : 00:18:8b:cc:xx:e3 00:00:00:00:00:e0
00:50:xx:c0:00:01 00:50:xx:c0:00:08  That makes it look much more comfortable , Is that so? ?
in addition ,NetworkInterface The interface also provides the following methods , You can refer to it .
* String displayName() Gets the display name of the network interface
* int getMTU() Returns the maximum transport unit for this interface (Maximum Transmission Unit,MTU)
* String getName() Gets the name of this network interface
* boolean isLoopback() Returns whether this network interface is a loopback interface
* boolean isPointToPoint() Returns whether this network interface is a point-to-point interface
* boolean isUp() Returns whether the network interface is turned on and running
* boolean isVirtual() Returns whether this interface is a virtual interface
 

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