Program: 121203
Project: 121203
Buggy source:
private static String getCurrentDbms(INode node){
  boolean hasMappingType=false;
  String currentDbms=null;
  for (  IElementParameter currentParam : node.getElementParameters()) {
    if (currentParam.getFieldType().equals(EParameterFieldType.MAPPING_TYPE) && currentParam.isShow(node.getElementParameters())) {
      currentDbms=(String)currentParam.getValue();
      hasMappingType=true;
    }
  }
  if (!hasMappingType) {
    IElementParameter schemaTypeParameter=node.getElementParameter("String_Node_Str");
    if (schemaTypeParameter == null) {
      return null;
    }
    String schemaType=(String)schemaTypeParameter.getValue();
    if (schemaType.equals("String_Node_Str")) {
      String metaRepositoryName=(String)node.getElementParameter("String_Node_Str").getValue();
      Connection connection=MetadataToolHelper.getConnectionFromRepository(metaRepositoryName);
      if (connection instanceof DatabaseConnection) {
        if (((DatabaseConnection)connection).getDatabaseType().equals(EDatabaseTypeName.GENERAL_JDBC.getDisplayName())) {
          currentDbms=(DBConnectionContextUtils.cloneOriginalValueConnection((DatabaseConnection)connection)).getDbmsId();
        }
 else {
          currentDbms=((DatabaseConnection)connection).getDbmsId();
        }
      }
    }
 else {
      String componentDbType="String_Node_Str";
      for (      IElementParameter param : (List<IElementParameter>)node.getElementParameters()) {
        if (param.getRepositoryValue() != null) {
          if (param.getRepositoryValue().equals("String_Node_Str")) {
            componentDbType=(String)param.getValue();
          }
        }
      }
      String componentProduct=EDatabaseTypeName.getTypeFromDbType(componentDbType).getProduct();
      if (EDatabaseTypeName.supportDbType(componentDbType)) {
        currentDbms=MetadataTalendType.getDefaultDbmsFromProduct(componentProduct).getId();
      }
    }
  }
  return currentDbms;
}

Fixed version (ground truth):
private static String getCurrentDbms(INode node){
  boolean hasMappingType=false;
  String currentDbms=null;
  for (  IElementParameter currentParam : node.getElementParameters()) {
    if (currentParam.getFieldType().equals(EParameterFieldType.MAPPING_TYPE) && currentParam.isShow(node.getElementParameters())) {
      currentDbms=(String)currentParam.getValue();
      hasMappingType=true;
    }
  }
  if (!hasMappingType) {
    IElementParameter schemaTypeParameter=node.getElementParameter("String_Node_Str");
    if (schemaTypeParameter == null) {
      return null;
    }
    String schemaType=(String)schemaTypeParameter.getValue();
    if (schemaType.equals("String_Node_Str")) {
      String metaRepositoryName=(String)node.getElementParameter("String_Node_Str").getValue();
      Connection connection=MetadataToolHelper.getConnectionFromRepository(metaRepositoryName);
      if (connection instanceof DatabaseConnection) {
        if (((DatabaseConnection)connection).getDatabaseType().equals(EDatabaseTypeName.GENERAL_JDBC.getDisplayName())) {
          currentDbms=(DBConnectionContextUtils.cloneOriginalValueConnection((DatabaseConnection)connection,true,null)).getDbmsId();
        }
 else {
          currentDbms=((DatabaseConnection)connection).getDbmsId();
        }
      }
    }
 else {
      String componentDbType="String_Node_Str";
      for (      IElementParameter param : (List<IElementParameter>)node.getElementParameters()) {
        if (param.getRepositoryValue() != null) {
          if (param.getRepositoryValue().equals("String_Node_Str")) {
            componentDbType=(String)param.getValue();
          }
        }
      }
      String componentProduct=EDatabaseTypeName.getTypeFromDbType(componentDbType).getProduct();
      if (EDatabaseTypeName.supportDbType(componentDbType)) {
        currentDbms=MetadataTalendType.getDefaultDbmsFromProduct(componentProduct).getId();
      }
    }
  }
  return currentDbms;
}