Program: 70170
Project: 70170
Buggy source:
public void perform(){
  Resource targetHost=tgtLoc.getHosts().getFirst();
  logger.debug("String_Node_Str" + Thread.currentThread().getName() + "String_Node_Str"+ getName()+ "String_Node_Str"+ tgtLoc);
synchronized (srcData) {
    if (tgtData != null) {
      MultiURI u;
      if ((u=srcData.alreadyAvailable(targetHost)) != null) {
        setFinalTarget(u.getPath());
        end(DataOperation.OpEndState.OP_OK);
        logger.debug("String_Node_Str" + Thread.currentThread().getName() + "String_Node_Str"+ getName()+ "String_Node_Str"+ targetHost+ "String_Node_Str"+ u.getPath());
        return;
      }
      Copy copyInProgress=null;
      if ((copyInProgress=srcData.alreadyCopying(tgtLoc)) != null) {
        String path=copyInProgress.tgtLoc.getURIInHost(targetHost).getPath();
        setFinalTarget(path);
        end(DataOperation.OpEndState.OP_IN_PROGRESS);
synchronized (copyInProgress.getEventListeners()) {
          copyInProgress.addEventListeners(getEventListeners());
        }
        logger.debug("String_Node_Str" + Thread.currentThread().getName() + "String_Node_Str"+ path+ "String_Node_Str");
        return;
      }
    }
    srcData.startCopy(this,tgtLoc);
  }
  try {
    specificCopy();
  }
 catch (  CopyException e) {
    end(DataOperation.OpEndState.OP_FAILED,e);
    return;
  }
 finally {
    DataLocation actualLocation;
synchronized (srcData) {
      actualLocation=srcData.finishedCopy(this);
    }
    if (tgtData != null) {
synchronized (tgtData) {
        tgtData.addLocation(actualLocation);
      }
    }
  }
  String path=tgtLoc.getURIInHost(targetHost).getPath();
  setFinalTarget(path);
synchronized (srcData) {
    end(DataOperation.OpEndState.OP_OK);
  }
  logger.debug("String_Node_Str" + getName());
}

Fixed version (ground truth):
public void perform(){
  Resource targetHost=tgtLoc.getHosts().getFirst();
  logger.debug("String_Node_Str" + Thread.currentThread().getName() + "String_Node_Str"+ getName()+ "String_Node_Str"+ tgtLoc);
synchronized (srcData) {
    if (tgtData != null) {
      MultiURI u;
      if ((u=srcData.alreadyAvailable(targetHost)) != null) {
        setFinalTarget(u.getPath());
        end(DataOperation.OpEndState.OP_OK);
        logger.debug("String_Node_Str" + Thread.currentThread().getName() + "String_Node_Str"+ getName()+ "String_Node_Str"+ targetHost+ "String_Node_Str"+ u.getPath());
        return;
      }
      Copy copyInProgress=null;
      if ((copyInProgress=srcData.alreadyCopying(tgtLoc)) != null) {
        String path=copyInProgress.tgtLoc.getURIInHost(targetHost).getPath();
        setFinalTarget(path);
        end(DataOperation.OpEndState.OP_IN_PROGRESS);
synchronized (copyInProgress.getEventListeners()) {
          copyInProgress.addEventListeners(getEventListeners());
        }
        logger.debug("String_Node_Str" + Thread.currentThread().getName() + "String_Node_Str"+ path+ "String_Node_Str");
        return;
      }
    }
    srcData.startCopy(this,tgtLoc);
  }
  try {
    logger.debug("String_Node_Str" + getName());
    specificCopy();
  }
 catch (  CopyException e) {
    end(DataOperation.OpEndState.OP_FAILED,e);
    return;
  }
 finally {
    DataLocation actualLocation;
synchronized (srcData) {
      actualLocation=srcData.finishedCopy(this);
    }
    if (tgtData != null) {
synchronized (tgtData) {
        tgtData.addLocation(actualLocation);
      }
    }
  }
  String path=tgtLoc.getURIInHost(targetHost).getPath();
  setFinalTarget(path);
synchronized (srcData) {
    end(DataOperation.OpEndState.OP_OK);
  }
  logger.debug("String_Node_Str" + getName() + "String_Node_Str");
}