// In a future Java8 world, this should produce a Stream<FieldConfig>, to avoid the double loop.
 private static Collection<FieldConfig> resultConfigs(WebConfig webConfig, ClassDescriptor cld) {
   final List<FieldConfig> fieldConfigs = getClassFieldConfigs(webConfig, cld);
   Iterator<FieldConfig> it = fieldConfigs.iterator();
   while (it.hasNext()) {
     FieldConfig f = it.next();
     if (!f.getShowInResults()) {
       it.remove();
     }
   }
   return fieldConfigs;
 }
  /**
   * Return a list of string paths that are defined as WebConfig to be shown in results. This will
   * include only attributes of the given class and not follow references. Optionally provide a
   * prefix to for creating a view for references/collections.
   *
   * @param type the class name to create a view for
   * @param model the model
   * @param webConfig we configuration
   * @param startingPath a path to prefix the class, can be null
   * @return the configured view paths for the class
   */
  public static List<String> getDefaultViewForClass(
      String type, Model model, WebConfig webConfig, String startingPath) {
    String prefix = startingPath;
    List<String> view = new ArrayList<String>();
    ClassDescriptor cld = model.getClassDescriptorByName(type);
    List<FieldConfig> fieldConfigs = getClassFieldConfigs(webConfig, cld);
    if (!StringUtils.isEmpty(prefix)) {
      try {
        // we can't add a subclass constraint, type must be same as the end of the prefix
        Path prefixPath = new Path(model, prefix);
        String prefixEndType = TypeUtil.unqualifiedName(prefixPath.getEndType().getName());
        if (!prefixEndType.equals(type)) {
          throw new IllegalArgumentException(
              "Mismatch between end type of prefix: "
                  + prefixEndType
                  + " and type parameter: "
                  + type);
        }
      } catch (PathException e) {
        LOG.error("Invalid path configured in webconfig for class: " + type);
      }
    } else {
      prefix = type;
    }

    for (FieldConfig fieldConfig : fieldConfigs) {
      String relPath = fieldConfig.getFieldExpr();
      // only add attributes, don't follow references, following references can be problematic
      // when subclasses get involved.
      if (fieldConfig.getShowInResults()) {
        try {
          Path path = new Path(model, prefix + "." + relPath);
          // use type (e.g. Protein) not prefix (e.g. Gene.proteins) to do
          // attribute check
          Path checkIsOnlyAttribute = new Path(model, type + "." + relPath);
          if (checkIsOnlyAttribute.isOnlyAttribute()) {
            view.add(path.getNoConstraintsString());
          }
        } catch (PathException e) {
          LOG.error("Invalid path configured in webconfig for class: " + type);
        }
      }
    }
    if (view.size() == 0) {
      for (AttributeDescriptor att : cld.getAllAttributeDescriptors()) {
        if (!"id".equals(att.getName())) {
          view.add(prefix + "." + att.getName());
        }
      }
    }
    return view;
  }
  /**
   * Used for making a query for a reference or collection. Only used when a user clicks on [show
   * all] under an inline table on an Object's report page. The type of that object is
   * "startingPath", eg. Department. This path will be prepended to every path in the query. The
   * "type" is the type of the reference/collection, eg. Employee.
   *
   * <p>TODO use getDefaultViewForClass() instead
   *
   * @param objType class of object we are querying for eg. Manager
   * @param model the model
   * @param webConfig the webconfig
   * @param fieldType the type of the field this object is in, eg Employee
   * @return query, eg. Department.employees.name
   */
  protected static PathQuery getQueryWithDefaultView(
      String objType, Model model, WebConfig webConfig, String fieldType) {
    String prefix = fieldType;
    PathQuery query = new PathQuery(model);
    ClassDescriptor cld = model.getClassDescriptorByName(objType);
    List<FieldConfig> fieldConfigs = getClassFieldConfigs(webConfig, cld);

    if (!StringUtils.isBlank(prefix)) {
      try {
        // if the type is different to the end of the prefix path, add a subclass constraint
        Path fieldPath = new Path(model, fieldType);
        String fieldEndType = TypeUtil.unqualifiedName(fieldPath.getEndType().getName());
        if (!fieldEndType.equals(objType)) {
          query.addConstraint(Constraints.type(fieldType, objType));
        }
      } catch (PathException e) {
        LOG.error("Invalid path configured in webconfig for class: " + objType);
      }
    }

    for (FieldConfig fieldConfig : fieldConfigs) {
      if (fieldConfig.getShowInResults()) {
        String path = prefix + "." + fieldConfig.getFieldExpr();
        int from = prefix.length() + 1;
        while (path.indexOf('.', from) != -1) {
          int dotPos = path.indexOf('.', from);
          int nextDot = path.indexOf('.', dotPos + 1);
          String outerJoin = nextDot == -1 ? path.substring(0, dotPos) : path.substring(0, nextDot);
          query.setOuterJoinStatus(outerJoin, OuterJoinStatus.OUTER);
          from = dotPos + 1;
        }
        query.addView(path);
      }
    }
    if (query.getView().size() == 0) {
      for (AttributeDescriptor att : cld.getAllAttributeDescriptors()) {
        if (!"id".equals(att.getName())) {
          query.addView(prefix + "." + att.getName());
        }
      }
    }
    return query;
  }
  /**
   * Return a list of string paths that are defined as WebConfig to be shown in results. This will
   * include attributes of the given class and follow references.
   *
   * @param type the class name to create a view for
   * @param model the model
   * @param webConfig we configuration
   * @return the configured view paths for the class
   */
  public static List<String> getDefaultViewForClass(String type, Model model, WebConfig webConfig) {
    List<String> view = new ArrayList<String>();
    ClassDescriptor cld = model.getClassDescriptorByName(type);
    List<FieldConfig> fieldConfigs = FieldConfigHelper.getClassFieldConfigs(webConfig, cld);

    for (FieldConfig fieldConfig : fieldConfigs) {
      String relPath = fieldConfig.getFieldExpr();
      // only add attributes, don't follow references, following references can be problematic
      // when subclasses get involved.
      if (fieldConfig.getShowInResults()) {
        try {
          Path path = new Path(model, type + "." + relPath);
          // add references
          if (path.isRootPath() || path.endIsReference()) {
            for (FieldConfig fc :
                FieldConfigHelper.getClassFieldConfigs(webConfig, path.getEndClassDescriptor())) {
              Path pathToAdd =
                  new Path(model, path.toStringNoConstraints() + "." + fc.getFieldExpr());
              if (pathToAdd.endIsAttribute()
                  && (!view.contains(pathToAdd.getNoConstraintsString()))
                  && (fc.getDisplayer() == null && fc.getShowInSummary())) {
                view.add(pathToAdd.getNoConstraintsString());
              }
            }
            // add collections
          } else if (!path.endIsCollection()) {
            view.add(path.getNoConstraintsString());
          }
        } catch (PathException e) {
          LOG.error("Invalid path configured in webconfig for class: " + type);
        }
      }
    }
    if (view.size() == 0) {
      for (AttributeDescriptor att : cld.getAllAttributeDescriptors()) {
        if (!"id".equals(att.getName())) {
          view.add(type + "." + att.getName());
        }
      }
    }
    return view;
  }