如何在Windows和/或Mac上的Java应用程序中找到我的"计算机描述"？

Question

我一直在努力寻找运行我的Java应用程序的计算机的"描述".

我所追求的是在本地网络上宣传我的电脑时用于DNS的名称(下面屏幕截图中的"iMac Mattijs").

在Windows XP上,可以在此处找到此名称:控制面板 - >系统 - >计算机名称 - >计算机描述.

在Mac OS 10.6上,可以在此处找到此名称:系统首选项 - >共享 - >计算机名称

下面的方法没有提供我正在寻找的名称.看看这段代码:

    System.out.println("COMPUTERNAME environment variable: " + System.getenv("COMPUTERNAME"));
    try { System.out.println("localhost name: " + InetAddress.getLocalHost().getHostName()); } 
    catch (UnknownHostException e1) {}

    try {
        Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();
        while (interfaces.hasMoreElements()) {
            NetworkInterface thisInterface = interfaces.nextElement();
            Enumeration<InetAddress> addresses = thisInterface.getInetAddresses();

            System.out.println("* network interface: " + thisInterface.getDisplayName());
             while (addresses.hasMoreElements()) {
                 InetAddress address = addresses.nextElement();
                 System.out.println(" - address: " + address.getCanonicalHostName());
             }
        }           
    } catch (SocketException e) {}

在Windows上,这会打印:

COMPUTERNAME environment variable: ARTTECH-51CA5F5
localhost name: arttech-51ca5f5
* network interface: MS TCP Loopback interface
 - address: localhost
* network interface: NVIDIA nForce Networking Controller - Packet Scheduler Miniport
* network interface: Broadcom 802.11n Network Adapter - Packet Scheduler Miniport
 - address: arttech-51ca5f5.lan
* network interface: Bluetooth Device (Personal Area Network)

在Mac上,我得到:

COMPUTERNAME environment variable: null
localhost name: imac-mattijs.lan 
* network interface: en1
 - address: imac-mattijs.lan
 - address: imac-mattijs.local
* network interface: lo0
 - address: localhost
 - address: fe80:0:0:0:0:0:0:1%1
 - address: localhost

但我正在寻找完整的字符串"iMac Mattijs".

任何线索都会非常受欢迎!

谢谢,Mattijs

Answer 1

Mac OS X 将计算机名称存储在系统配置动态存储中。其标准接口是通过系统配置框架实现的。执行此 API 的命令行工具是scutil：

$ scutil --get computerName
Hermes is awesome!

（我暂时将计算机名称更改为带有空格和标点符号的名称，以便可以轻松地将其与主机名区分开来，在本例中主机名类似于hermes-is-awesome.local。）

您可以使用 JNI 轻松地与之交互：

class SCDynamicStore {
  public native String copyComputerName();
  static {
    System.loadLibrary("SCDynamicStore");
  }
}

class HostnameSC {
  public static void
  main(String[] args) {
    SCDynamicStore store = new SCDynamicStore();
    String computerName = store.copyComputerName();
    System.out.format("computer name: %s\n", computerName);
  }
}

不时javac FILE.java地javah SCDynamicStore。这会产生SCDynamicStore.h. 将其复制到SCDynamicStore.c并编辑为：

#include "SCDynamicStore.h"
#include <SystemConfiguration/SystemConfiguration.h>

JNIEXPORT jstring JNICALL
Java_SCDynamicStore_copyComputerName(JNIEnv *env, jobject o)
{
  SCDynamicStoreRef store = NULL;
  CFStringRef computerName = NULL;
  CFStringEncoding UTF8 = kCFStringEncodingUTF8;
  CFIndex length;
  Boolean ok;
  jstring computerNameString = NULL;
  CFStringRef process = CFSTR("com.me.jni.SCDynamicStore");

  store = SCDynamicStoreCreate(NULL, process, NULL/*callout*/, NULL/*ctx*/);
  if (!store) {
    fprintf(stderr, "failed to get store\n");
    goto CantCreateStore;
  }

  computerName = SCDynamicStoreCopyComputerName(store, NULL);
  if (!computerName) {
    fprintf(stderr, "failed to copy computer name\n");
    goto CantCopyName;
  }

  length = CFStringGetLength(computerName);
  length = CFStringGetMaximumSizeForEncoding(length, UTF8);
  {
    char utf8[length];
    if (!CFStringGetCString(computerName, utf8, sizeof(utf8), UTF8)) {
      fprintf(stderr, "failed to convert to utf8\n");
      goto CantConvert;
    }
    computerNameString = (*env)->NewStringUTF(env, utf8);
  }

CantConvert:
  CFRelease(computerName);
CantCopyName:
  CFRelease(store), store = NULL;
CantCreateStore:
  return computerNameString;
}

（您可以通过使用 Obj-C 免费桥接并利用 来简化代码。在某些错误情况下，-[NSString UTF8String]可能需要抛出异常而不是仅返回。）NULL

然后您可以使用 来编译它clang -shared -I/Developer/SDKs/MacOSX10.6.sdk/System/Library/Frameworks/JavaVM.framework/Headers/ -framework CoreFoundation -framework SystemConfiguration SCDynamicStore.c -o libSCDynamicStore.dylib。

现在，只要libSCDynamicStore.dylib是LD_LIBRARY_PATH在当前目录中，您就可以运行该应用程序：

$ java HostnameSC
computer name: Hermes is awesome!