private void removeInvalidBreakpoints() {
    ArrayList<Breakpoint> toDelete = new ArrayList<Breakpoint>();

    for (Breakpoint breakpoint : getBreakpoints()) {
      if (!breakpoint.isValid()) {
        toDelete.add(breakpoint);
      }
    }

    for (final Breakpoint aToDelete : toDelete) {
      removeBreakpoint(aToDelete);
    }
  }