Program: 120379
Project: 120379
Buggy source:
public boolean canCollapse(){
  List<String> connList=new ArrayList<String>();
  List<String> metaList=new ArrayList<String>();
  if (node.getIncomingConnections().size() > 1) {
    for (    IConnection conn : node.getIncomingConnections()) {
      if (conn.getConnectorName().startsWith("String_Node_Str")) {
        metaList.add(conn.getMetaName());
      }
    }
    for (    NodeContainer nodeContainer : this.nodeContainers) {
      Node connNode=nodeContainer.getNode();
      IElementParameter elePa=this.node.getElementParameter(connNode.getJoblet_unique_name());
      if (elePa != null) {
        boolean isTri=false;
        IJobletProviderService service=(IJobletProviderService)GlobalServiceRegister.getDefault().getService(IJobletProviderService.class);
        if (service != null) {
          isTri=service.isTriggerNode(connNode);
        }
        if (isTri) {
          IElementParameter elechild=elePa.getChildParameters().get("String_Node_Str");
          if (elechild != null) {
            if (elechild.getValue() != null && (elechild.getValue() instanceof String)) {
              metaList.remove(elechild.getValue());
            }
          }
        }
 else {
          IElementParameter elechild=elePa.getChildParameters().get("String_Node_Str");
          if (elechild != null) {
            if ((elechild.getValue() == null || "String_Node_Str".equals(elechild.getValue()))) {
              return false;
            }
 else {
              if (elechild.getValue() instanceof String) {
                if (connList.contains((String)elechild.getValue())) {
                  return false;
                }
 else {
                  connList.add((String)elechild.getValue());
                }
              }
            }
          }
        }
      }
    }
    if (metaList.size() > 0) {
      return false;
    }
  }
  return true;
}

Fixed version (ground truth):
public boolean canCollapse(){
  List<String> connList=new ArrayList<String>();
  List<String> metaList=new ArrayList<String>();
  if (node.getIncomingConnections().size() > 1) {
    for (    IConnection conn : node.getIncomingConnections()) {
      if (conn.getConnectorName().startsWith("String_Node_Str")) {
        metaList.add(conn.getMetaName());
      }
    }
    for (    NodeContainer nodeContainer : this.nodeContainers) {
      Node connNode=nodeContainer.getNode();
      IElementParameter elePa=this.node.getElementParameter(connNode.getJoblet_unique_name());
      if (elePa != null) {
        boolean isTri=false;
        IJobletProviderService service=(IJobletProviderService)GlobalServiceRegister.getDefault().getService(IJobletProviderService.class);
        if (service != null) {
          isTri=service.isTriggerNode(connNode);
        }
        if (isTri) {
          IElementParameter elechild=elePa.getChildParameters().get("String_Node_Str");
          if (elechild != null) {
            if (elechild.getValue() != null && (elechild.getValue() instanceof String)) {
              metaList.remove(elechild.getValue());
            }
          }
        }
 else {
          IElementParameter elechild=elePa.getChildParameters().get("String_Node_Str");
          if (elechild != null) {
            if ((elechild.getValue() == null || "String_Node_Str".equals(elechild.getValue()))) {
              return false;
            }
 else {
              if (elechild.getValue() instanceof String) {
                if (connList.contains(elechild.getValue())) {
                  return false;
                }
 else {
                  connList.add((String)elechild.getValue());
                }
              }
            }
          }
        }
      }
    }
    if (metaList.size() > 0) {
      return false;
    }
  }
  return true;
}