Program: 18112
Project: 18112
Buggy source:
/** 
 * Main procedure for the replica responding to query. The replica checks if the requested instances are decided by it, and if yes - it appends them to response.
 */
private void handleQuery(CatchUpQuery query,int sender){
  if (query.isSnapshotRequest()) {
    Message m;
    Snapshot lastSnapshot=storage.getLastSnapshot();
    if (lastSnapshot != null)     m=new CatchUpSnapshot(storage.getView(),query.getSentTime(),lastSnapshot);
 else     m=new CatchUpResponse(storage.getView(),query.getSentTime(),new Vector<ConsensusInstance>());
    network.sendMessage(m,sender);
    logger.info("String_Node_Str" + query.toString() + "String_Node_Str"+ sender+ "String_Node_Str");
    return;
  }
  SortedMap<Integer,ConsensusInstance> log=storage.getLog().getInstanceMap();
  if (log.isEmpty()) {
    if (storage.getLastSnapshot() != null)     sendSnapshotOnlyResponse(query,sender);
    return;
  }
  Integer lastKey=log.lastKey();
  InnerResponseSender responseSender=new InnerResponseSender(query,sender);
  int i;
  for (  Pair<Integer,Integer> range : query.getInstanceIdRangeArray()) {
    for (i=range.key(); i <= range.value() && i <= lastKey; ++i) {
      ConsensusInstance consensusInstance=log.get(i);
      if (consensusInstance == null) {
        sendSnapshotOnlyResponse(query,sender);
        return;
      }
      if (consensusInstance.getState() == LogEntryState.DECIDED)       responseSender.add(consensusInstance);
    }
  }
  for (  int instanceId : query.getInstanceIdArray()) {
    if (instanceId >= lastKey)     continue;
    ConsensusInstance consensusInstance=log.get(instanceId);
    if (consensusInstance == null) {
      sendSnapshotOnlyResponse(query,sender);
      return;
    }
    if (consensusInstance.getState() == LogEntryState.DECIDED)     responseSender.add(consensusInstance);
  }
  responseSender.flush();
  logger.info("String_Node_Str" + query.toString() + "String_Node_Str"+ sender+ "String_Node_Str");
}

Fixed version (ground truth):
/** 
 * Main procedure for the replica responding to query. The replica checks if the requested instances are decided by it, and if yes - it appends them to response.
 */
private void handleQuery(CatchUpQuery query,int sender){
  if (query.isSnapshotRequest()) {
    Message m;
    Snapshot lastSnapshot=storage.getLastSnapshot();
    if (lastSnapshot != null)     m=new CatchUpSnapshot(storage.getView(),query.getSentTime(),lastSnapshot);
 else     m=new CatchUpResponse(storage.getView(),query.getSentTime(),new Vector<ConsensusInstance>());
    network.sendMessage(m,sender);
    logger.info("String_Node_Str" + query.toString() + "String_Node_Str"+ sender+ "String_Node_Str");
    return;
  }
  SortedMap<Integer,ConsensusInstance> log=storage.getLog().getInstanceMap();
  if (log.isEmpty()) {
    if (storage.getLastSnapshot() != null)     sendSnapshotOnlyResponse(query,sender);
    return;
  }
  Integer lastKey=log.lastKey();
  InnerResponseSender responseSender=new InnerResponseSender(query,sender);
  int i;
  for (  Pair<Integer,Integer> range : query.getInstanceIdRangeArray()) {
    for (i=range.key(); i <= range.value() && i <= lastKey; ++i) {
      ConsensusInstance consensusInstance=log.get(i);
      if (consensusInstance == null) {
        sendSnapshotOnlyResponse(query,sender);
        return;
      }
      if (consensusInstance.getState() == LogEntryState.DECIDED)       responseSender.add(consensusInstance);
    }
  }
  for (  int instanceId : query.getInstanceIdArray()) {
    if (instanceId > lastKey)     continue;
    ConsensusInstance consensusInstance=log.get(instanceId);
    if (consensusInstance == null) {
      sendSnapshotOnlyResponse(query,sender);
      return;
    }
    if (consensusInstance.getState() == LogEntryState.DECIDED)     responseSender.add(consensusInstance);
  }
  responseSender.flush();
  logger.info("String_Node_Str" + query.toString() + "String_Node_Str"+ sender+ "String_Node_Str");
}