indexed_map library

A high-performance hybrid data structure that combines the benefits of both Map and List in a single container.

IndexedMap provides O(1) lookup by ID, O(1) indexed access, and O(1) index-of-ID resolution while maintaining ordered iteration. It's ideal for scenarios where you need both fast lookups and ordered iteration, such as:

• User lists with fast lookup by ID
• Message/chat histories with chronological order
• Caching with insertion order preservation
• Any collection where both random access and ordered iteration are needed

Key features:

• O(1) lookup by ID via internal Map
• O(1) indexed access via internal List
• O(1) index-of-ID via reverse index Map
• Configurable duplicate handling policies
• Ordered iteration maintaining insertion/move order
• In-place sorting without losing ID associations
• Bulk operations (addAll, removeWhere)

Classes

IndexedMap<T extends MapIndexable<I>, I>

A hybrid container that provides O(1) lookup by id and ordered/indexed access.

ItemWrapper<T extends MapIndexable<I>, I>

Wrapper to allow future metadata without changing the container shape. Add fields like: createdAt, isPinned, etc.

MapIndexable<I>

An item that can be indexed by a stable id of type I.

Enums

DuplicatePolicy

How to handle inserting an item whose id already exists.