如何使用Java读取注册表值？ [重复]

如何解决如何使用Java读取注册表值？ [重复]

|                                                                                                                   这个问题已经在这里有了答案：                                                      

解决方法

        这显示了如何读取注册表，但可以扩展为写入操作：如何读取Windows注册表

import java.io.*;

public class RegQuery {

  private static final String REGQUERY_UTIL = \"reg query \";
  private static final String REGSTR_TOKEN = \"REG_SZ\";
  private static final String REGDWORD_TOKEN = \"REG_DWORD\";

  private static final String PERSONAL_FOLDER_CMD = REGQUERY_UTIL +
    \"\\\"HKCU\\\\Software\\\\Microsoft\\\\Windows\\\\CurrentVersion\\\\\"
     + \"Explorer\\\\Shell Folders\\\" /v Personal\";
  private static final String CPU_SPEED_CMD = REGQUERY_UTIL +
    \"\\\"HKLM\\\\HARDWARE\\\\DESCRIPTION\\\\System\\\\CentralProcessor\\\\0\\\"\"
     + \" /v ~MHz\";
  private static final String CPU_NAME_CMD = REGQUERY_UTIL +
   \"\\\"HKLM\\\\HARDWARE\\\\DESCRIPTION\\\\System\\\\CentralProcessor\\\\0\\\"\"
     + \" /v ProcessorNameString\";

  public static String getCurrentUserPersonalFolderPath() {
    try {
      Process process = Runtime.getRuntime().exec(PERSONAL_FOLDER_CMD);
      StreamReader reader = new StreamReader(process.getInputStream());

      reader.start();
      process.waitFor();
      reader.join();

      String result = reader.getResult();
      int p = result.indexOf(REGSTR_TOKEN);

      if (p == -1)
         return null;

      return result.substring(p + REGSTR_TOKEN.length()).trim();
    }
    catch (Exception e) {
      return null;
    }
  }

  public static String getCPUSpeed() {
    try {
      Process process = Runtime.getRuntime().exec(CPU_SPEED_CMD);
      StreamReader reader = new StreamReader(process.getInputStream());

      reader.start();
      process.waitFor();
      reader.join();

      String result = reader.getResult();
      int p = result.indexOf(REGDWORD_TOKEN);

      if (p == -1)
         return null;

      // CPU speed in Mhz (minus 1) in HEX notation,convert it to DEC
      String temp = result.substring(p + REGDWORD_TOKEN.length()).trim();
      return Integer.toString
          ((Integer.parseInt(temp.substring(\"0x\".length()),16) + 1));
    }
    catch (Exception e) {
      return null;
    }
  }

  public static String getCPUName() {
    try {
      Process process = Runtime.getRuntime().exec(CPU_NAME_CMD);
      StreamReader reader = new StreamReader(process.getInputStream());

      reader.start();
      process.waitFor();
      reader.join();

      String result = reader.getResult();
      int p = result.indexOf(REGSTR_TOKEN);

      if (p == -1)
         return null;

      return result.substring(p + REGSTR_TOKEN.length()).trim();
    }
    catch (Exception e) {
      return null;
    }
  }

  static class StreamReader extends Thread {
    private InputStream is;
    private StringWriter sw;

    StreamReader(InputStream is) {
      this.is = is;
      sw = new StringWriter();
    }

    public void run() {
      try {
        int c;
        while ((c = is.read()) != -1)
          sw.write(c);
        }
        catch (IOException e) { ; }
      }

    String getResult() {
      return sw.toString();
    }
  }

  public static void main(String s[]) {
    System.out.println(\"Personal directory : \"
       + getCurrentUserPersonalFolderPath());
    System.out.println(\"CPU Name : \" + getCPUName());
    System.out.println(\"CPU Speed : \" + getCPUSpeed() + \" Mhz\");
  }
}

    ,        有一个教程向您显示不使用

Runtime.exec()

函数，而是专门使用

java.util.prefs.WindowsPreferences

。