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Java Collection, PriorityQueue Exercises: Remove all the elements from a priority queue

Java Collection, PriorityQueue Exercises: Exercise-5 with Solution

Write a Java program to remove all the elements from a priority queue.

Sample Solution:-

Java Code:

import java.util.*;
  public class Example5 {
  public static void main(String[] args) {
   // Create Priority Queue
           PriorityQueue<String> pq1 = new PriorityQueue<String>();  
   // use add() method to add values in the Priority Queue
          pq1.add("Red");
          pq1.add("Green");
          pq1.add("Black");
          pq1.add("White");
    System.out.println("Original Priority Queue: "+pq1);
   
   // Removing all the elements from the Priority Queue
    pq1.clear();
 
    System.out.println("The New Priority Queue: " + pq1);
  } 
}

Sample Output:

Original Priority Queue: [Black, Red, Green, White]                    
The New Priority Queue: []

Java Code Editor:

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Java: Tips of the Day

Try and catch:

Java is excellent at catching errors, but it can only recover gracefully if you tell it what to do. The cascading hierarchy of attempting to perform an action in Java starts with try, falls back to catch, and ends with finally. Should the try clause fail, then catch is invoked, and in the end, there's always finally to perform some sensible action regardless of the results. Here's an example:

try {
        cmd = parser.parse(opt, args); 
       
        if(cmd.hasOption("help")) {
                HelpFormatter helper = new HelpFormatter();
                helper.printHelp("Hello ", opt);
                System.exit(0);
                }
        else {
                if(cmd.hasOption("shell") || cmd.hasOption("s")) {
                String target = cmd.getOptionValue("tgt");
                } // else
        } // fi
} catch (ParseException err) {
        System.out.println(err);
        System.exit(1);
        } //catch
        finally {
                new Hello().helloWorld(opt);
        } //finally
} //try

It's a robust system that attempts to avoid irrecoverable errors or, at least, to provide you with the option to give useful feedback to the user. Use it often, and your users will thank you!

Ref: https://red.ht/3EZc9OC