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Java Collection, HashSet Exercises: Convert a hash set to a List/ArrayList

Java Collection, HashSet Exercises: Exercise-9 with Solution

Write a Java program to convert a hash set to a List/ArrayList.

Sample Solution:

Java Code:

import java.util.*;

  public class Exercise9 {
  public static void main(String[] args) {
         // Create a empty hash set
     HashSet<String> h_set = new HashSet<String>();
   // use add() method to add values in the hash set
          h_set.add("Red");
          h_set.add("Green");
          h_set.add("Black");
          h_set.add("White");
          h_set.add("Pink");
          h_set.add("Yellow");
      System.out.println("Original Hash Set: " + h_set);
    
    // Create a List from HashSet elements
     List<String> list = new ArrayList<String>(h_set);
 
     // Display ArrayList elements
     System.out.println("ArrayList contains: "+ list);
  }
}

Sample Output:

Original Hash Set: [Red, White, Pink, Yellow, Black, Green]            
ArrayList contains: [Red, White, Pink, Yellow, Black, Green]

Pictorial Presentation:

Java Collection, ArrayList Exercises: Convert a hash set to a List/ArrayList

Flowchart:

Flowchart: Convert a hash set to a List/ArrayList.

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