자바로 윈도우 레지스트리를 읽고 쓸수있나요?

자바로 윈도우 레지스트리를 읽고 쓰는게 가능한가요?

1답변

  • 좋아요

    0

    싫어요
    채택취소하기

    구글 검색하다가 아주 좋은 코드를 발견해서 답변드립니다. 이 코드는

    1. 레지스트리의 어떤 부분도 읽고 쓸 수 있습니다.
    2. JNI를 쓰지 않습니다.
    3. 외부 응용프로그램에서도 잘 동작합니다.
    4. 윈도우 API를 사용하지 않습니다. ( 직접적으로)

    그냥 순수 자바 코드인데요. java.util.prefs.Preferences 클래스의 private메소드에 접근하기위해서 리플렉션을 사용합니다. 클래스 내부는 매우 복잡하지만 밑에 예제처럼 사용은 쉽습니다.

    String value = WinRegistry.readString (
        WinRegistry.HKEY_LOCAL_MACHINE,                             //HKEY
       "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion",           //Key
       "ProductName");                                              //ValueName
        System.out.println("Windows Distribution = " + value); 
    

    이 코드는 레지스트리에서 윈도우 Distribution을 가져오는 코드입니다.

    import java.lang.reflect.InvocationTargetException;
    import java.lang.reflect.Method;
    import java.util.HashMap;
    import java.util.Map;
    import java.util.ArrayList;
    import java.util.List;
    import java.util.prefs.Preferences;
    
    public class WinRegistry {
      public static final int HKEY_CURRENT_USER = 0x80000001;
      public static final int HKEY_LOCAL_MACHINE = 0x80000002;
      public static final int REG_SUCCESS = 0;
      public static final int REG_NOTFOUND = 2;
      public static final int REG_ACCESSDENIED = 5;
    
      private static final int KEY_ALL_ACCESS = 0xf003f;
      private static final int KEY_READ = 0x20019;
      private static Preferences userRoot = Preferences.userRoot();
      private static Preferences systemRoot = Preferences.systemRoot();
      private static Class<? extends Preferences> userClass = userRoot.getClass();
      private static Method regOpenKey = null;
      private static Method regCloseKey = null;
      private static Method regQueryValueEx = null;
      private static Method regEnumValue = null;
      private static Method regQueryInfoKey = null;
      private static Method regEnumKeyEx = null;
      private static Method regCreateKeyEx = null;
      private static Method regSetValueEx = null;
      private static Method regDeleteKey = null;
      private static Method regDeleteValue = null;
    
      static {
        try {
          regOpenKey = userClass.getDeclaredMethod("WindowsRegOpenKey",
              new Class[] { int.class, byte[].class, int.class });
          regOpenKey.setAccessible(true);
          regCloseKey = userClass.getDeclaredMethod("WindowsRegCloseKey",
              new Class[] { int.class });
          regCloseKey.setAccessible(true);
          regQueryValueEx = userClass.getDeclaredMethod("WindowsRegQueryValueEx",
              new Class[] { int.class, byte[].class });
          regQueryValueEx.setAccessible(true);
          regEnumValue = userClass.getDeclaredMethod("WindowsRegEnumValue",
              new Class[] { int.class, int.class, int.class });
          regEnumValue.setAccessible(true);
          regQueryInfoKey = userClass.getDeclaredMethod("WindowsRegQueryInfoKey1",
              new Class[] { int.class });
          regQueryInfoKey.setAccessible(true);
          regEnumKeyEx = userClass.getDeclaredMethod(  
              "WindowsRegEnumKeyEx", new Class[] { int.class, int.class,  
                  int.class });  
          regEnumKeyEx.setAccessible(true);
          regCreateKeyEx = userClass.getDeclaredMethod(  
              "WindowsRegCreateKeyEx", new Class[] { int.class,  
                  byte[].class });  
          regCreateKeyEx.setAccessible(true);  
          regSetValueEx = userClass.getDeclaredMethod(  
              "WindowsRegSetValueEx", new Class[] { int.class,  
                  byte[].class, byte[].class });  
          regSetValueEx.setAccessible(true); 
          regDeleteValue = userClass.getDeclaredMethod(  
              "WindowsRegDeleteValue", new Class[] { int.class,  
                  byte[].class });  
          regDeleteValue.setAccessible(true); 
          regDeleteKey = userClass.getDeclaredMethod(  
              "WindowsRegDeleteKey", new Class[] { int.class,  
                  byte[].class });  
          regDeleteKey.setAccessible(true); 
        }
        catch (Exception e) {
          e.printStackTrace();
        }
      }
    
      private WinRegistry() {  }
    
      /**
       * Read a value from key and value name
       * @param hkey   HKEY_CURRENT_USER/HKEY_LOCAL_MACHINE
       * @param key
       * @param valueName
       * @return the value
       * @throws IllegalArgumentException
       * @throws IllegalAccessException
       * @throws InvocationTargetException
       */
      public static String readString(int hkey, String key, String valueName) 
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        if (hkey == HKEY_LOCAL_MACHINE) {
          return readString(systemRoot, hkey, key, valueName);
        }
        else if (hkey == HKEY_CURRENT_USER) {
          return readString(userRoot, hkey, key, valueName);
        }
        else {
          throw new IllegalArgumentException("hkey=" + hkey);
        }
      }
    
      /**
       * Read value(s) and value name(s) form given key 
       * @param hkey  HKEY_CURRENT_USER/HKEY_LOCAL_MACHINE
       * @param key
       * @return the value name(s) plus the value(s)
       * @throws IllegalArgumentException
       * @throws IllegalAccessException
       * @throws InvocationTargetException
       */
      public static Map<String, String> readStringValues(int hkey, String key) 
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        if (hkey == HKEY_LOCAL_MACHINE) {
          return readStringValues(systemRoot, hkey, key);
        }
        else if (hkey == HKEY_CURRENT_USER) {
          return readStringValues(userRoot, hkey, key);
        }
        else {
          throw new IllegalArgumentException("hkey=" + hkey);
        }
      }
    
      /**
       * Read the value name(s) from a given key
       * @param hkey  HKEY_CURRENT_USER/HKEY_LOCAL_MACHINE
       * @param key
       * @return the value name(s)
       * @throws IllegalArgumentException
       * @throws IllegalAccessException
       * @throws InvocationTargetException
       */
      public static List<String> readStringSubKeys(int hkey, String key) 
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        if (hkey == HKEY_LOCAL_MACHINE) {
          return readStringSubKeys(systemRoot, hkey, key);
        }
        else if (hkey == HKEY_CURRENT_USER) {
          return readStringSubKeys(userRoot, hkey, key);
        }
        else {
          throw new IllegalArgumentException("hkey=" + hkey);
        }
      }
    
      /**
       * Create a key
       * @param hkey  HKEY_CURRENT_USER/HKEY_LOCAL_MACHINE
       * @param key
       * @throws IllegalArgumentException
       * @throws IllegalAccessException
       * @throws InvocationTargetException
       */
      public static void createKey(int hkey, String key) 
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        int [] ret;
        if (hkey == HKEY_LOCAL_MACHINE) {
          ret = createKey(systemRoot, hkey, key);
          regCloseKey.invoke(systemRoot, new Object[] { new Integer(ret[0]) });
        }
        else if (hkey == HKEY_CURRENT_USER) {
          ret = createKey(userRoot, hkey, key);
          regCloseKey.invoke(userRoot, new Object[] { new Integer(ret[0]) });
        }
        else {
          throw new IllegalArgumentException("hkey=" + hkey);
        }
        if (ret[1] != REG_SUCCESS) {
          throw new IllegalArgumentException("rc=" + ret[1] + "  key=" + key);
        }
      }
    
      /**
       * Write a value in a given key/value name
       * @param hkey
       * @param key
       * @param valueName
       * @param value
       * @throws IllegalArgumentException
       * @throws IllegalAccessException
       * @throws InvocationTargetException
       */
      public static void writeStringValue
        (int hkey, String key, String valueName, String value) 
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        if (hkey == HKEY_LOCAL_MACHINE) {
          writeStringValue(systemRoot, hkey, key, valueName, value);
        }
        else if (hkey == HKEY_CURRENT_USER) {
          writeStringValue(userRoot, hkey, key, valueName, value);
        }
        else {
          throw new IllegalArgumentException("hkey=" + hkey);
        }
      }
    
      /**
       * Delete a given key
       * @param hkey
       * @param key
       * @throws IllegalArgumentException
       * @throws IllegalAccessException
       * @throws InvocationTargetException
       */
      public static void deleteKey(int hkey, String key) 
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        int rc = -1;
        if (hkey == HKEY_LOCAL_MACHINE) {
          rc = deleteKey(systemRoot, hkey, key);
        }
        else if (hkey == HKEY_CURRENT_USER) {
          rc = deleteKey(userRoot, hkey, key);
        }
        if (rc != REG_SUCCESS) {
          throw new IllegalArgumentException("rc=" + rc + "  key=" + key);
        }
      }
    
      /**
       * delete a value from a given key/value name
       * @param hkey
       * @param key
       * @param value
       * @throws IllegalArgumentException
       * @throws IllegalAccessException
       * @throws InvocationTargetException
       */
      public static void deleteValue(int hkey, String key, String value) 
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        int rc = -1;
        if (hkey == HKEY_LOCAL_MACHINE) {
          rc = deleteValue(systemRoot, hkey, key, value);
        }
        else if (hkey == HKEY_CURRENT_USER) {
          rc = deleteValue(userRoot, hkey, key, value);
        }
        if (rc != REG_SUCCESS) {
          throw new IllegalArgumentException("rc=" + rc + "  key=" + key + "  value=" + value);
        }
      }
    
      // =====================
    
      private static int deleteValue
        (Preferences root, int hkey, String key, String value)
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        int[] handles = (int[]) regOpenKey.invoke(root, new Object[] {
            new Integer(hkey), toCstr(key), new Integer(KEY_ALL_ACCESS) });
        if (handles[1] != REG_SUCCESS) {
          return handles[1];  // can be REG_NOTFOUND, REG_ACCESSDENIED
        }
        int rc =((Integer) regDeleteValue.invoke(root,  
            new Object[] { 
              new Integer(handles[0]), toCstr(value) 
              })).intValue();
        regCloseKey.invoke(root, new Object[] { new Integer(handles[0]) });
        return rc;
      }
    
      private static int deleteKey(Preferences root, int hkey, String key) 
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        int rc =((Integer) regDeleteKey.invoke(root,  
            new Object[] { new Integer(hkey), toCstr(key) })).intValue();
        return rc;  // can REG_NOTFOUND, REG_ACCESSDENIED, REG_SUCCESS
      }
    
      private static String readString(Preferences root, int hkey, String key, String value)
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        int[] handles = (int[]) regOpenKey.invoke(root, new Object[] {
            new Integer(hkey), toCstr(key), new Integer(KEY_READ) });
        if (handles[1] != REG_SUCCESS) {
          return null; 
        }
        byte[] valb = (byte[]) regQueryValueEx.invoke(root, new Object[] {
            new Integer(handles[0]), toCstr(value) });
        regCloseKey.invoke(root, new Object[] { new Integer(handles[0]) });
        return (valb != null ? new String(valb).trim() : null);
      }
    
      private static Map<String,String> readStringValues
        (Preferences root, int hkey, String key)
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        HashMap<String, String> results = new HashMap<String,String>();
        int[] handles = (int[]) regOpenKey.invoke(root, new Object[] {
            new Integer(hkey), toCstr(key), new Integer(KEY_READ) });
        if (handles[1] != REG_SUCCESS) {
          return null;
        }
        int[] info = (int[]) regQueryInfoKey.invoke(root,
            new Object[] { new Integer(handles[0]) });
    
        int count = info[0]; // count  
        int maxlen = info[3]; // value length max
        for(int index=0; index<count; index++)  {
          byte[] name = (byte[]) regEnumValue.invoke(root, new Object[] {
              new Integer
                (handles[0]), new Integer(index), new Integer(maxlen + 1)});
          String value = readString(hkey, key, new String(name));
          results.put(new String(name).trim(), value);
        }
        regCloseKey.invoke(root, new Object[] { new Integer(handles[0]) });
        return results;
      }
    
      private static List<String> readStringSubKeys
        (Preferences root, int hkey, String key)
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        List<String> results = new ArrayList<String>();
        int[] handles = (int[]) regOpenKey.invoke(root, new Object[] {
            new Integer(hkey), toCstr(key), new Integer(KEY_READ) 
            });
        if (handles[1] != REG_SUCCESS) {
          return null;
        }
        int[] info = (int[]) regQueryInfoKey.invoke(root,
            new Object[] { new Integer(handles[0]) });
    
        int count  = info[0]; // Fix: info[2] was being used here with wrong results. Suggested by davenpcj, confirmed by Petrucio
        int maxlen = info[3]; // value length max
        for(int index=0; index<count; index++)  {
          byte[] name = (byte[]) regEnumKeyEx.invoke(root, new Object[] {
              new Integer
                (handles[0]), new Integer(index), new Integer(maxlen + 1)
              });
          results.add(new String(name).trim());
        }
        regCloseKey.invoke(root, new Object[] { new Integer(handles[0]) });
        return results;
      }
    
      private static int [] createKey(Preferences root, int hkey, String key)
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        return  (int[]) regCreateKeyEx.invoke(root,
            new Object[] { new Integer(hkey), toCstr(key) });
      }
    
      private static void writeStringValue 
        (Preferences root, int hkey, String key, String valueName, String value) 
        throws IllegalArgumentException, IllegalAccessException,
        InvocationTargetException 
      {
        int[] handles = (int[]) regOpenKey.invoke(root, new Object[] {
            new Integer(hkey), toCstr(key), new Integer(KEY_ALL_ACCESS) });
    
        regSetValueEx.invoke(root,  
            new Object[] { 
              new Integer(handles[0]), toCstr(valueName), toCstr(value) 
              }); 
        regCloseKey.invoke(root, new Object[] { new Integer(handles[0]) });
      }
    
      // utility
      private static byte[] toCstr(String str) {
        byte[] result = new byte[str.length() + 1];
    
        for (int i = 0; i < str.length(); i++) {
          result[i] = (byte) str.charAt(i);
        }
        result[str.length()] = 0;
        return result;
      }
    }
    

    이건 원본 소스인데요 그냥 복붙하시면 됩니다.

    • 사용 요청 예시는 잘돼는데, 같은 방식으로 dword값을 출력하려면 null이라고 뜨네요 readString 메소드는 숫자값을 출력 못하나요? Monsterkat 2017.3.1 23:03

ᕕ( ᐛ )ᕗ
로그인이 필요합니다

작성한 답변에 다른 개발자들이 댓글을 작성하거나 댓글에 좋아요/싫어요를 할 수 있기 때문에 계정을 필요로 합니다.