code: @SuppressWarnings("unchecked")
      public static <T> T ifTrue(boolean _b, T _t) {
          return _b ? _t : (_t instanceof CharSequence ? (T) "" : null);
      }
docs: Returns the second parameter if the condition is true
  or null if the condition is false. Returns empty string
  instead of null for implementors of {@link CharSequence}.
  @param _b condition
  @param _t object
  @return object or null