The syntax of the entrySet() method is:
hashmap.entrySet() Here, hashmap is an object of the HashMap class.
entrySet() Parameters
The entrySet() method does not take any parameter.
entrySet() Return Value
- returns a set view of all the entries of a hashmap
Note: The set view means all entries of the hashmap are viewed as a set. Entries are not converted to a set.
Example 1: Java HashMap entrySet()
import java.util.HashMap; class Main { public static void main(String[] args) { // create an HashMap HashMap<String, Integer> prices = new HashMap<>(); // insert entries to the HashMap prices.put("Shoes", 200); prices.put("Bag", 300); prices.put("Pant", 150); System.out.println("HashMap: " + prices); // return set view of mappings System.out.println("Set View: " + prices.entrySet()); } } Output
HashMap: {Pant=150, Bag=300, Shoes=200} Set View: [Pant=150, Bag=300, Shoes=200] In the above example, we have created a hashmap named prices. Notice the expression,
prices.entrySet() Here, the entrySet() method returns a set view of all the entries from the hashmap.
The entrySet() method can be used with the for-each loop to iterate through each entry of the hashmap.
Example 2: entrySet() Method in for-each Loop
import java.util.HashMap; import java.util.Map.Entry; class Main { public static void main(String[] args) { // Creating a HashMap HashMap<String, Integer> numbers = new HashMap<>(); numbers.put("One", 1); numbers.put("Two", 2); numbers.put("Three", 3); System.out.println("HashMap: " + numbers); // access each entry of the hashmap System.out.print("Entries: "); // entrySet() returns a set view of all entries // for-each loop access each entry from the view for(Entry<String, Integer> entry: numbers.entrySet()) { System.out.print(entry); System.out.print(", "); } } } Output
HashMap: {One=1, Two=2, Three=3} Entries: One=1, Two=2, Three=3, In the above example, we have imported the java.util.Map.Entry package. The Map.Entry is the nested class of the Map interface. Notice the line,
Entry<String, Integer> entry : numbers.entrySet() Here, the entrySet() method returns a set view of all the entries. The Entry class allows us to store and print each entry from the view.
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