How to Implement a Map with Multiple Keys?

Implementing a Map with Multiple Keys

The conventional Map data structure operates with a single key for each value. However, some scenarios require a map-like structure that allows access to values using multiple keys.

In this context, if the keys are guaranteed to be unique, an effective approach is to utilize two separate Maps: Map and Map. This setup enables efficient retrieval of values using either K1 or K2 as the key.

For convenience, a wrapper class can be designed to provide a unified interface for interacting with these two Maps. This wrapper class can define methods such as getByKey1(K1 key), getByKey2(K2 key), containsKey1(K1 key), and containsKey2(K2 key).

It's worth noting that using tuples or pairs as keys for a single Map would not fulfill the requirement, as it would preclude searching for values based on only one of the keys. Maps rely on hash codes and equality checks for efficient access, making it impractical to handle multiple keys within a single key object.

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