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Java Collection, LinkedList Exercises: Test an linked list is empty or not

Java Collection, LinkedList Exercises: Exercise-25 with Solution

Write a Java program to test an linked list is empty or not.

Sample Solution:-

Java Code:

import java.util.LinkedList;
import java.util.Collections;
  public class Exercise25 {
  public static void main(String[] args) {
          LinkedList<String> c1= new LinkedList<String>();
          c1.add("Red");
          c1.add("Green");
          c1.add("Black");
          c1.add("White");
          c1.add("Pink");
          System.out.println("Original linked list: " + c1);
          System.out.println("Check the above linked list is empty or not! "+c1.isEmpty());
          c1.removeAll(c1);
          System.out.println("Linked list after remove all elements "+c1);   
          System.out.println("Check the above linked list is empty or not! "+c1.isEmpty());
   }
}

Sample Output:

Original linked list: [Red, Green, Black, White, Pink]                 
Check the above linked list is empty or not! false                     
Linked list after remove all elements []                               
Check the above linked list is empty or not! true 

Pictorial Presentation:

Java Collection Linked-list: Test an linked list is empty or not.

Flowchart:

Flowchart: Test an linked list is empty or not

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