hashmap

Java includes a number of data structures for storing and manipulating collections of objects. The 'LinkedHashMap' class, which is an extension of the 'HashMap' class, is one of the important classes in the Java Collections Framework. LinkedHashMap, unlike HashMap, preserves the order of its items depending on the insertion order, making it helpful in cases where the order of components must be maintained based on their arrival time.

HashMap is a component of the Java Collections Framework that implements the Map interface. It offers a key-value pair data structure in which elements are stored as a combination of keys and their corresponding values. HashMap does not support duplicate keys, but it does support mapping multiple values to the same key. It provides constant-time performance for simple operations like as element addition, removal, and retrieval.