PTNumberTree

@interface PTNumberTree : NSObject

A NumberTree is a common data structure in PDF. See section 3.8.6 ‘Number Trees’ in PDF Reference Manual for more details.

A number tree serves a similar purpose to a dictionary - associating keys and values - but by different means. NumberTrees allow efficient storage of very large association collections (number/Obj* maps). A NumberTree can have many more entries than a SDF/Cos dictionary can.

Sample code:

   PDFDoc doc("../Data/test.pdf");
   NumberTree labels(doc.GetRoot().Get("PageLabels").Value());
   if (labels.IsValid()) {
     // Traversing the NumberTree
     for (NumberTreeIterator i = labels.GetIterator(); i.HasNext(); i.Next())
         cout << "Key: " << i.Key().GetNumber() << endl;
   }

  • Create a high level NumberTree wrapper around an existing SDF/Cos NumberTree. This does not copy the object.

    Declaration

    Objective-C

    - (instancetype)initWithNumber_tree:(PTObj *)number_tree;

    Swift

    init!(number_tree: PTObj!)

    Parameters

    number_tree

    SDF/Cos root of the NumberTree object.

  • Declaration

    Objective-C

    - (BOOL)IsValid;

    Swift

    func isValid() -> Bool

    Return Value

    whether this is a valid (non-null) NumberTree. If the function returns false the underlying SDF/Cos object is null and the NumberTree object should be treated as null as well.

  • Undocumented

    Declaration

    Objective-C

    - (PTDictIterator*)GetNumberIteratorWithKey: (int)key;

    Swift

    func getNumberIterator(withKey key: Int32) -> PTDictIterator!

  • Search for the specified key in the NumberTree.

    Sample code: NumberTreeIterator i = dests.Find(5); if (i.HasNext()) { cout << “Key: ” << i.GetKey()->GetNumber() << endl; cout << “Value: ” << i.GetValue()->GetType() << endl; }

    Declaration

    Objective-C

    - (PTDictIterator *)GetIterator;

    Swift

    func getIterator() -> PTDictIterator!

    Parameters

    key

    the number representing the key to be found.

    Return Value

    If the key is present the function returns a NumberTreeIterator the points to the given Key/Value pair. If the key is not found the function returns End() (a non-valid) iterator.

  • Undocumented

    Declaration

    Objective-C

    - (PTObj*)GetValue: (int)key;

    Swift

    func getValue(_ key: Int32) -> PTObj!

  • Puts a new entry in the name tree. If an entry with this number is already in the tree, it is replaced.

    Declaration

    Objective-C

    - (void)Put:(int)key value:(PTObj *)value;

    Swift

    func put(_ key: Int32, value: PTObj!)

    Parameters

    key

    A number representing the key of the new entry.
    value

    the value associated with the key. It can be any SDF::Obj.

  • Removes the specified object from the tree. Does nothing if no object with that number exists.

    Declaration

    Objective-C

    - (void)EraseNumberTreeEntryWithKey:(int)key;

    Swift

    func eraseNumberTreeEntry(withKey key: Int32)

    Parameters

    key

    A number representing the key of the entry to be removed.

  • Removes the NumberTree entry pointed by the iterator.

    Declaration

    Objective-C

    - (void)EraseNumberTreeEntryWithPos:(PTDictIterator *)pos;

    Swift

    func eraseNumberTreeEntry(withPos pos: PTDictIterator!)

    Parameters

    pos

    dictionary iterator object that points to the NumberTree entry to be removed

  • Declaration

    Objective-C

    - (PTObj *)GetSDFObj;

    Swift

    func getSDFObj() -> PTObj!

    Return Value

    the object to the underlying SDF/Cos object. If the NumberTree.IsValid() returns false the SDF/Cos object is NULL.