getting first level of categorisation from Notes view

Question

I have a categorized Notes view, let say the first categorized column is TypeOfVehicle the second categorized column is Model and the third categorized column is Manufacturer.

I would like to collect only the values for the first category and return it as json object:

I am facing two problems: - I can not read the value for the category, the column values are emptry and when I try to access the underlying document it is null

• the script won't hop over to the category/sibling on the same level.

can someone explain me what am I doing wrong here?

private Object getFirstCategory() {
        JsonJavaObject json = new JsonJavaObject();
        try{
            String server = null;
            String filepath = null;
            server = props.getProperty("server");
            filepath = props.getProperty("filename");
            Database db;
            db = utils.getSession().getDatabase(server, filepath);
            if (db.isOpen()) {
                View vw = db.getView("transport");
                if (null != vw) {
                    vw.setAutoUpdate(false);
                    ViewNavigator nav;
                    nav = vw.createViewNav();

                    JsonJavaArray arr = new JsonJavaArray();
                    Integer count = 0;
                    ViewEntry tmpentry;
                    ViewEntry entry = nav.getFirst();
                    while (null != entry) {                     
                        Vector<?> columnValues = entry.getColumnValues();                   
                        if(entry.isCategory()){
                            System.out.println("entry notesid = " + entry.getNoteID());
                            Document doc = entry.getDocument();
                            if(null != doc){
                                if (doc.hasItem("TypeOfVehicle ")){
                                    System.out.println("category has not " + "TypeOfVehicle ");
                                }
                                else{
                                    System.out.println("category IS " + doc.getItemValueString("TypeOfVehicle "));
                                }
                            } else{
                                System.out.println("doc is null");
                            }                           

                            JsonJavaObject row = new JsonJavaObject();
                            JsonJavaObject jo = new JsonJavaObject();

                            String TypeOfVehicle  = String.valueOf(columnValues.get(0));
                            if (null != TypeOfVehicle ) {
                                if (!TypeOfVehicle .equals("")){
                                    jo.put("TypeOfVehicle ", TypeOfVehicle );
                                } else{
                                    jo.put("TypeOfVehicle ", "Not categorized");
                                }                           
                            } else {
                                jo.put("TypeOfVehicle ", "Not categorized");
                            }       

                            row.put("request", jo);
                            arr.put(count, row);
                            count++;

                            tmpentry = nav.getNextSibling(entry);
                            entry.recycle();
                            entry = tmpentry; 


                        } else{
                            //tmpentry = nav.getNextCategory();
                            //entry.recycle();
                            //entry = tmpentry;
                        }


                    }

                    json.put("data", arr);

                    vw.setAutoUpdate(true);
                    vw.recycle();
                }
            }
        } catch (Exception e) {
            OpenLogUtil.logErrorEx(e, JSFUtil.getXSPContext().getUrl().toString(), Level.SEVERE, null);
        }
        return json;        
    }

Answer 1

What you're doing wrong is trying to treat any single view entry as both a category and a document. A single view entry can only be one of a category, a document, or a total.

If you have an entry for which isCategory() returns true, then for the same entry:

• isDocument() will return false.
• getDocument() will return null.
• getNoteID() will return an empty string.

If the only thing you need is top-level categories, then get the first entry from the navigator and iterate over entries using nav.getNextSibling(entry) as you're already doing, but:

• Don't try to get documents, note ids, or fields.
• Use entry.getColumnValues().get(0) to get the value of the first column for each category.

If the view contains any uncategorised documents, it's possible that entry.getColumnValues().get(0) might throw an exception, so you should also check that entry.getColumnValues().size() is at least 1 before trying to get a value.

If you need any extra data beyond just top-level categories, then note that subcategories and documents are children of their parent categories.
If an entry has a subcategory, nav.getChild(entry) will get the first subcategory of that entry.
If an entry has no subcategories, but is a category which contains documents, nav.getChild(entry) will get the first document in that category.