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How to Iterate Map Entries (Keys and Values). The HashMap can be iterated over with the forEach() method. We can apply Iterator concept for any collection object and it is a universal cursor. As of Java 8, we can use the forEach method as well as the iterator class to loop over a map. The forEach() is a new method introduced in Java 8 to iterate over collections. In Map based collection, the location of the value is. We can use Iterator to get objects one by one from any collection object. HashMap does not guarantee order, hence the insertion order will not be maintained while traversing. Ways to Iterating a map before Java 8 2.1. Iterate using java 8 Stream forEach() method.Ģ.Iterate using java 8 forEach() method, functional style.

Iterate using entrySet() through enhanced for-each loop.Iterate using keySet() through enhanced for-each loop.Different ways of Iterate a mapįollowing are the most commonly used approaches to iterate any map in java.

These methods are common for any Map implementation classes. The iterator will run through each element in. On the other hand, if you want to remove entries, while iterating over HashMap, may be only. You can use the HashMap keys, HashMap values, and HashMap Entry Object to iterate over the HashMap in Java. And also we are going to see usage of keySet(), values(), entrySet(), forEach() methods of Java Map interface. How come the solution with two loops (nested) is faster than a two pass solution that. This makes it also the fastest way to loop over HashMap in Java. In this article we are going to see how to iterate java map in different approaches with simple examples, we will go through different ways of iterating map in java before java 8 and from Java 8 and above.