public static File getUserDir() {
        return new File(System.getProperty(USER_DIR_KEY));
    }
<p>
Gets the user directory as a {@code File}.
</p>

@return a directory
@throws SecurityException if a security manager exists and its {@code checkPropertyAccess} method doesn't allow
access to the specified system property.
@see System#getProperty(String)
@since 2.1
android/android_framework/base/src/main/java/lang3/SystemUtils.java