Program: 120591
Project: 120591
Buggy source:
@Override @SuppressWarnings("String_Node_Str") public void execute(){
  process.setActivate(false);
  for (  INode node : nodeList) {
    if (node.getJobletNode() != null) {
      continue;
    }
    NodeContainer nodeContainer=((Node)node).getNodeContainer();
    ((Process)process).removeNodeContainer(nodeContainer);
    List<IConnection> inputList=(List<IConnection>)node.getIncomingConnections();
    List<IConnection> outputList=(List<IConnection>)node.getOutgoingConnections();
    boolean builtIn=node.getConnectorFromType(EConnectionType.FLOW_MAIN).isMultiSchema() | node.getConnectorFromType(EConnectionType.TABLE).isMultiSchema();
    for (    IConnection connection : inputList) {
      if (connection != null && connection.getSourceNodeConnector() != null) {
        connection.getSourceNodeConnector().setCurLinkNbOutput(connection.getSourceNodeConnector().getCurLinkNbOutput() - 1);
      }
      INode prevNode=connection.getSource();
      if ((prevNode instanceof Node) && ((Node)prevNode).getJobletNode() != null) {
        Node jobletnode=(Node)prevNode.getJobletNode();
        ((JobletContainer)jobletnode.getNodeContainer()).getOutputs().remove(connection);
        if (!nodeList.contains(jobletnode)) {
          boolean builtInJobletNode=jobletnode.getConnectorFromType(EConnectionType.FLOW_MAIN).isMultiSchema() | node.getConnectorFromType(EConnectionType.TABLE).isMultiSchema();
          jobletnode.removeOutput(connection);
          if (!builtInJobletNode)           process.removeUniqueConnectionName(connection.getUniqueName());
        }
      }
      if (!nodeList.contains(prevNode)) {
        boolean builtInPrevNode=prevNode.getConnectorFromType(EConnectionType.FLOW_MAIN).isMultiSchema() | node.getConnectorFromType(EConnectionType.TABLE).isMultiSchema();
        prevNode.removeOutput(connection);
        if (!builtInPrevNode)         process.removeUniqueConnectionName(connection.getUniqueName());
      }
    }
    for (    IConnection connection : outputList) {
      INode nextNode=connection.getTarget();
      if ((nextNode instanceof Node) && ((Node)nextNode).getJobletNode() != null) {
        Node jobletnode=(Node)nextNode.getJobletNode();
        ((JobletContainer)jobletnode.getNodeContainer()).getInputs().remove(connection);
        if (!nodeList.contains(jobletnode)) {
          jobletnode.removeInput(connection);
          boolean builtInJobletNode=jobletnode.getConnectorFromType(EConnectionType.FLOW_MAIN).isMultiSchema() | node.getConnectorFromType(EConnectionType.TABLE).isMultiSchema();
          if (!builtInJobletNode)           process.removeUniqueConnectionName(connection.getUniqueName());
        }
      }
      if (!nodeList.contains(nextNode)) {
        INodeConnector nodeConnector=nextNode.getConnectorFromType(connection.getLineStyle());
        nodeConnector.setCurLinkNbInput(nodeConnector.getCurLinkNbInput() - 1);
        nextNode.removeInput(connection);
        if (nextNode != null) {
          for (int i=0; i < nextNode.getIncomingConnections().size(); i++) {
            Connection nextNodeConnection=(Connection)nextNode.getIncomingConnections().get(i);
            nextNodeConnection.updateName();
          }
        }
      }
      if (!builtIn) {
        process.removeUniqueConnectionName(connection.getUniqueName());
      }
    }
    if (builtIn) {
      for (      IMetadataTable meta : node.getMetadataList()) {
        String metaName=meta.getTableName();
        process.removeUniqueConnectionName(metaName);
      }
      final List<String> names=CorePlugin.getDefault().getMapperService().getJoinTableNames(node.getExternalData());
      if (!names.isEmpty()) {
        joinTableNames.addAll(names);
        for (        String name : joinTableNames) {
          process.removeUniqueConnectionName(name);
        }
      }
    }
  }
  process.setActivate(true);
  process.checkStartNodes();
  process.checkProcess();
}

Fixed version (ground truth):
@Override @SuppressWarnings("String_Node_Str") public void execute(){
  process.setActivate(false);
  for (  INode node : nodeList) {
    if (node.getJobletNode() != null) {
      continue;
    }
    NodeContainer nodeContainer=((Node)node).getNodeContainer();
    ((Process)process).removeNodeContainer(nodeContainer);
    List<IConnection> inputList=(List<IConnection>)node.getIncomingConnections();
    List<IConnection> outputList=(List<IConnection>)node.getOutgoingConnections();
    boolean builtIn=node.getConnectorFromType(EConnectionType.FLOW_MAIN).isMultiSchema() | node.getConnectorFromType(EConnectionType.TABLE).isMultiSchema();
    for (    IConnection connection : inputList) {
      if (connection != null && connection.getSourceNodeConnector() != null) {
        connection.getSourceNodeConnector().setCurLinkNbOutput(connection.getSourceNodeConnector().getCurLinkNbOutput() - 1);
      }
      INode prevNode=connection.getSource();
      if ((prevNode instanceof Node) && ((Node)prevNode).getJobletNode() != null) {
        Node jobletnode=(Node)prevNode.getJobletNode();
        ((JobletContainer)jobletnode.getNodeContainer()).getOutputs().remove(connection);
        if (!nodeList.contains(jobletnode)) {
          boolean builtInJobletNode=jobletnode.getConnectorFromType(EConnectionType.FLOW_MAIN).isMultiSchema() | node.getConnectorFromType(EConnectionType.TABLE).isMultiSchema();
          jobletnode.removeOutput(connection);
          if (!builtInJobletNode)           process.removeUniqueConnectionName(connection.getUniqueName());
        }
      }
      if (!nodeList.contains(prevNode)) {
        boolean builtInPrevNode=prevNode.getConnectorFromType(EConnectionType.FLOW_MAIN).isMultiSchema() | node.getConnectorFromType(EConnectionType.TABLE).isMultiSchema();
        prevNode.removeOutput(connection);
        if (!builtInPrevNode)         process.removeUniqueConnectionName(connection.getUniqueName());
      }
    }
    for (    IConnection connection : outputList) {
      INode nextNode=connection.getTarget();
      if ((nextNode instanceof Node) && ((Node)nextNode).getJobletNode() != null) {
        Node jobletnode=(Node)nextNode.getJobletNode();
        ((JobletContainer)jobletnode.getNodeContainer()).getInputs().remove(connection);
        if (!nodeList.contains(jobletnode)) {
          jobletnode.removeInput(connection);
          boolean builtInJobletNode=jobletnode.getConnectorFromType(EConnectionType.FLOW_MAIN).isMultiSchema() | node.getConnectorFromType(EConnectionType.TABLE).isMultiSchema();
          if (!builtInJobletNode)           process.removeUniqueConnectionName(connection.getUniqueName());
        }
      }
      if (!nodeList.contains(nextNode)) {
        INodeConnector nodeConnector=nextNode.getConnectorFromType(connection.getLineStyle());
        nodeConnector.setCurLinkNbInput(nodeConnector.getCurLinkNbInput() - 1);
        nextNode.removeInput(connection);
        if (nextNode != null) {
          for (int i=0; i < nextNode.getIncomingConnections().size(); i++) {
            Connection nextNodeConnection=(Connection)nextNode.getIncomingConnections().get(i);
            nextNodeConnection.updateName();
          }
        }
        if (nextNode.getExternalNode() instanceof AbstractNode) {
          ((AbstractNode)nextNode.getExternalNode()).removeInput(connection);
        }
      }
      if (!builtIn) {
        process.removeUniqueConnectionName(connection.getUniqueName());
      }
    }
    if (builtIn) {
      for (      IMetadataTable meta : node.getMetadataList()) {
        String metaName=meta.getTableName();
        process.removeUniqueConnectionName(metaName);
      }
      final List<String> names=CorePlugin.getDefault().getMapperService().getJoinTableNames(node.getExternalData());
      if (!names.isEmpty()) {
        joinTableNames.addAll(names);
        for (        String name : joinTableNames) {
          process.removeUniqueConnectionName(name);
        }
      }
    }
  }
  process.setActivate(true);
  process.checkStartNodes();
  process.checkProcess();
}