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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

getEnumMap

Converts to enum to Map where key is the name and value is Enum itself. 

public static <E extends Enum<E>> Map<String, E> getEnumMap(final Class<E> enumClass) {
    return Arrays.stream(enumClass.getEnumConstants())
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}

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