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Java Method Exercises: Display the middle character of a string

Java Method: Exercise-3 with Solution

Write a Java method to display the middle character of a string.

Note: a) If the length of the string is odd there will be two middle characters.
b) If the length of the string is even there will be one middle character.

Test Data:
Input a string: 350

Pictorial Presentation:

Java Method Exercises: Display the middle character of a string

Sample Solution:

Java Code:

import java.util.Scanner;
public class Exercise3 {
  public static void main(String[] args)
    {
        Scanner in = new Scanner(System.in);
        System.out.print("Input a string: ");
        String str = in.nextLine();
        System.out.print("The middle character in the string: " + middle(str)+"\n");
    }
 public static String middle(String str)
    {
        int position;
        int length;
        if (str.length() % 2 == 0)
        {
            position = str.length() / 2 - 1;
            length = 2;
        }
        else
        {
            position = str.length() / 2;
            length = 1;
        }
        return str.substring(position, position + length);
    }
}

Sample Output:

Input a string: 350                                                                                           
The middle character in the string: 5

Flowchart:

Flowchart: Display the middle character of a string

Java Code Editor:

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Previous: Write a Java method to compute the average of three numbers.
Next: Write a Java method to count all vowels in a string.

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Java: Tips of the Day

Array vs ArrayLists:

The main difference between these two is that an Array is of fixed size so once you have created an Array you cannot change it but the ArrayList is not of fixed size. You can create instances of ArrayLists without specifying its size. So if you create such instances of an ArrayList without specifying its size Java will create an instance of an ArrayList of default size.

Once an ArrayList is full it re-sizes itself. In fact, an ArrayList is internally supported by an array. So when an ArrayList is resized it will slow down its performance a bit as the contents of the old Array must be copied to a new Array.

At the same time, it's compulsory to specify the size of an Array directly or indirectly while creating it. And also Arrays can store both primitives and objects while ArrayLists only can store objects.

Ref: https://bit.ly/3o8L2KH