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Java
Java Data Structures focused on Java Data Structures and related concepts.
Data structures are ways to store and organize data so you can use it efficiently.
Before we explore ArrayList , HashSet , HashMap , and other data structures in more detail, it's important to understand that all of these are part of something bigger - the Java Collections Framewor…
The List interface is part of the Java Collections Framework and represents an ordered collection of elements.
An ArrayList is like a resizable array .
The LinkedList class is a collection which can contain many objects of the same type, just like the ArrayList .
Another useful class in the java.util package is the Collections class, which include the sort() method for sorting lists alphabetically or numerically.
The Set interface is part of the Java Collections Framework and is used to store a collection of unique elements .
A HashSet is a collection of elements where every element is unique .
A TreeSet is a collection that stores unique elements in sorted order .
A LinkedHashSet is a collection that stores unique elements and remembers the order they were added .
The Map interface is a part of the Java Collections Framework and is used to store key-value pairs . Each key must be unique, but values can be duplicated.
A HashMap stores items in key/value pairs , where each key maps to a specific value.
A TreeMap is a collection that stores key/value pairs in sorted order by key .
A LinkedHashMap stores keys and values, and keeps them in the same order you put them in.
An Iterator is an object that can be used to loop through collections , like ArrayList and HashSet .
In the previous chapters, you learned how data structures (like ArrayList , HashMap , etc.) are used to store and organize data.