Since Java 5, it is denoted as It allows us to store the null elements as well, but there should be only one null key. Hello, maybe I have stupid question but I cannot iterate HashMap... How can I do it? This example shows how to iterate LinkedHashMap in Java. For more specific, the BiConsumer is a functional interface which has a single method void accept(T t, U u); which takes 2 parameters and returns nothing. import java.util. ; both keys and values are in String-type only Using stream() in Java 8 This is also using in Java 8. Iterating over the HashMap's entrySet using Java 8 forEach How HashMap works in java Most common interview questions are How HashMap works in java, “How get and put method of HashMap work internally”. Since Java 8, you can use the Map.forEach() method to iterate through a map. This Java HashMap Tutorial Explains What is a HashMap in Java and How to use it. Key is unique Remember that we cannot iterate over map directly using iterators, because Map interface is not the part of Collection.All maps in Java implements Map interface. The values() method can also be used with the for-each loop to iterate through each value of the hashmap. super K, ? The example also shows various ways to iterate over LinkedHashMap keys, values and entries using an iterator and for loop. Java queries related to “how to iterate hashmap in java” iterator on hashmap iteration of Keys in a HashMap must be unique.HashMap is called an associative array or a dictionary in other programming languages. The entrySet() method of hashmap, provides us a set of all entries or key-value pairs stored in the hashmap which we called EntrySet and this EntrySet can be iterated as a collection. 2) Iterate through values of the HashMap Use this approach if you are interested only in the values stored in the HashMap. How to iterate Map in Java In Java, iteration over Map can be done in various ways. Here I am trying to explain internal functionality with an easy example. This Java Example shows how to iterate through the values contained in the HashMap object. It allows us to store the null elements as well, but there should be only one null key. In this tutorial we will learn how to loop HashMap using following methods: For loop While loop + Iterator Example: In the below example we are iterating Hi Chaitanya, Thank you very much for your wonderful and Helpful HashMap is one of those data structures that we use a lot in our code, almost on a daily basis. Entry < , This is the default method of the Map interface which takes a BiConsumer . We also had a short ride to the methods HashMap in Java was introduced in Java 1.2 release along with all other Collection utilities.HashMap in Java provides the basic implementation of Map interface of Java. 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