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Java Collection, HashMap Exercises: Get a set view of the keys contained in this map

Java Collection, HashMap Exercises: Exercise-11 with Solution

Write a Java program to get a set view of the keys contained in this map.

Sample Solution:-

Java Code:

import java.util.*;  
public class Example11 {  
     public static void main(String args[]){  
 
  HashMap<Integer,String> hash_map= new HashMap<Integer,String>();  
  
  hash_map.put(1,"Red");
  hash_map.put(2,"Green");
  hash_map.put(3,"Black");
  hash_map.put(4,"White");
  hash_map.put(5,"Blue");
  
  // get keyset value from map
   Set keyset = hash_map.keySet();
      
  // check key set values
   System.out.println("Key set values are: " + keyset);  
 }
}

Sample Output:

Key set values are: [1, 2, 3, 4, 5]

Java Code Editor:

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Java: Tips of the Day

Choice between Float and Double:

Data type Bytes used Significant figures (decimal)
Float 4 7
Double 8 15

Double is often preferred over float in software where precision is important because of the following reasons:
Most processors take nearly the same amount of processing time to perform operations on Float and Double. Double offers far more precision in the same amount of computation time.

Ref: https://bit.ly/3oj7K2K