2.3.10 The List Class

This section provides information about the List class.

Parent class

Dictionary

Child classes

Element (structure)

Description

The List class is a Dictionary subclass that is used for representing lists populated by the methods Dictionary::listObjects(), Dictionary::listIndexes(), and Dictionary::listEvents().

Methods

Beginning with NDB 8.0.29, this class has three methods, listed here:

• a constructor (List())

• a destructor (~List())

• a clear() method

None of the methods just listed take any arguments.

Calling the constructor creates a new List whose count and elements attributes are both set equal to 0.

The clear() method, introduced in NDB 8.0.29, removes all data from the list. You can use this to prepare an existing List for reuse with listEvents(), listIndexes(), or listObjects().

The destructor (~List()) removes all elements and their properties. Beginning with NDB 8.0.29, it first invokes clear() before doing so.

The definition of this class can be found in /storage/ndb/include/ndbapi/NdbDictionary.hpp.

Attributes

A List has the following two attributes:

• count, an unsigned integer, which stores the number of elements in the list.

• elements, a pointer to an array of Element data structures contained in the list. See Section 2.3.4, “The Element Structure”.

Types

The List class also defines the Element structure.