From Java 10, you can use the var keyword to declare a HashMap variable without writing the type twice. The compiler figures out the type from the value you assign.

All HashMap Methods A list of all HashMap methods can be found in the table below. Some methods use the type of the HashMap's entries as a parameter or return value. The type of the …

From Java 10, you can use the var keyword to declare a LinkedHashMap variable without writing the type twice. The compiler figures out the type from the value you assign.

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HashMap A HashMap stores key-value pairs, which are great when you want to store values and find them by a key (like a name or ID):

From Java 10, you can use the var keyword to declare a HashSet variable without writing the type twice. The compiler figures out the type from the value you assign.

From Java 10, you can use the var keyword to declare an ArrayList variable without writing the type twice. The compiler figures out the type from the value you assign.

Common Map Methods ... Map vs. Set vs. List ... Next, we'll look at how to use HashMap to store items in key/value pairs.

Java TreeMap A TreeMap is a collection that stores key/value pairs in sorted order by key. It is part of the java.util package and implements the Map interface. Tip: Unlike HashMap, which …

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