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Java Collection, ArrayList Exercises: Test an array list is empty or not

Java Collection, ArrayList Exercises: Exercise-18 with Solution

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

Pictorial Presentation:

Java Collection, ArrayList Exercises: Test an array list is empty or not.

Sample Solution:-

Java Code:

import java.util.ArrayList;
import java.util.Collections;
  public class Exercise18 {
  public static void main(String[] args) {
          ArrayList<String> c1= new ArrayList<String>();
          c1.add("Red");
          c1.add("Green");
          c1.add("Black");
          c1.add("White");
          c1.add("Pink");
          System.out.println("Original array list: " + c1);
          System.out.println("Checking the above array list is empty or not! "+c1.isEmpty());
          c1.removeAll(c1);
          System.out.println("Array list after remove all elements "+c1);   
          System.out.println("Checking the above array list is empty or not! "+c1.isEmpty());
   }
}

Sample Output:

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

Flowchart:

Flowchart: Test an array list is empty or not.

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