code: @Nullable
    public static Boolean parseBoolObjExact (@Nullable final String sStr, @Nullable final Boolean aDefault)
    {
      if (Boolean.TRUE.toString ().equalsIgnoreCase (sStr))
        return Boolean.TRUE;
      if (Boolean.FALSE.toString ().equalsIgnoreCase (sStr))
        return Boolean.FALSE;
      return aDefault;
    }
docs: Returns a <code>Boolean</code> with a value represented by the specified
  string. The <code>Boolean</code> returned represents a <code>true</code>
  value if the string argument is not <code>null</code> and is equal,
  ignoring case, to the string {@code "true"}, and it will return
  <code>false</code> if the string argument is not <code>null</code> and is
  equal, ignoring case, to the string {@code "false"}. In all other cases
  <code>aDefault</code> is returned.
  
  @param sStr
  The string to be parsed. May be <code>null</code>.
  @param aDefault
  The default value to be returned if the value is neither "true" nor
  "false". May be <code>null</code>.
  @return the <code>Boolean</code> value represented by the string. Never
  <code>null</code>.