2 * Copyright (C) 2014, United States Government, as represented by the
3 * Administrator of the National Aeronautics and Space Administration.
6 * The Java Pathfinder core (jpf-core) platform is licensed under the
7 * Apache License, Version 2.0 (the "License"); you may not use this file except
8 * in compliance with the License. You may obtain a copy of the License at
10 * http://www.apache.org/licenses/LICENSE-2.0.
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
19 package gov.nasa.jpf.listener;
21 import gov.nasa.jpf.Config;
22 import gov.nasa.jpf.search.Search;
23 import gov.nasa.jpf.vm.VM;
26 * little listener that tries to detect endless while() loops by counting
27 * backjumps, breaking transitions if the count exceeds a threshold, and
28 * then checking if program states match. If they do, there would be no progress
31 public class EndlessLoopDetector extends IdleFilter {
33 boolean foundEndlessLoop = false;
35 public EndlessLoopDetector(Config config) {
38 action = Action.BREAK;
42 public void stateAdvanced(Search search) {
43 if (brokeTransition && search.isVisitedState()) {
44 foundEndlessLoop = true;
49 public boolean check(Search search, VM vm) {
50 return !foundEndlessLoop;
54 public void reset () {
55 foundEndlessLoop = false;