common_helper/src/main/java/com/xiongyingqi/util/GetDocumentPathDemo.java
public static String getMyDocumentsFromWinRegistry() {
        try {
            Process process = Runtime.getRuntime().exec(PERSONAL_FOLDER_CMD);
            StreamReader streamreader = new StreamReader(process.getInputStream());

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

            String result = streamreader.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 getMyDocumentsFromWinRegistry() {
        try {
            Process process = Runtime.getRuntime().exec(PERSONAL_FOLDER_CMD);
            StreamReader streamreader = new StreamReader(process.getInputStream());

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

            String result = streamreader.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;
        }
    }
returns the Path to the "My Documents" folder or <code>null</code>

@return {@link String}