Java Coding Round Questions Asked in Interviews (With Solutions)

Here is a curated list of Java programming questions asked during the coding rounds of companies like TCS, Infosys, Wipro, Capgemini, and Cognizant. Each problem includes a simple and clean solution that’s ideal for freshers and entry-level roles.

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🧠 1. Reverse Each Word in a Sentence

Company: Infosys

Input: "Java is awesome"
Output: "avaJ si emosewa"

public class ReverseWords {
    public static void main(String[] args) {
        String input = "Java is awesome";
        String[] words = input.split(" ");
        StringBuilder result = new StringBuilder();

        for (String word : words) {
            result.append(new StringBuilder(word).reverse()).append(" ");
        }

        System.out.println(result.toString().trim());
    }
}

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🔢 2. Count Number of Digits, Letters, and Special Characters

Company: Capgemini

Input: "Java123@#!"
Output: Letters=4, Digits=3, Specials=3

public class CountTypes {
    public static void main(String[] args) {
        String str = "Java123@#!";
        int letters = 0, digits = 0, specials = 0;

        for (char ch : str.toCharArray()) {
            if (Character.isLetter(ch)) letters++;
            else if (Character.isDigit(ch)) digits++;
            else specials++;
        }

        System.out.println("Letters=" + letters + ", Digits=" + digits + ", Specials=" + specials);
    }
}

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🔁 3. Print Fibonacci Series up to N Terms

Company: Wipro

Input: 6
Output: 0 1 1 2 3 5

public class FibonacciSeries {
    public static void main(String[] args) {
        int n = 6, a = 0, b = 1;
        System.out.print(a + " " + b + " ");
        for (int i = 2; i < n; i++) {
            int c = a + b;
            System.out.print(c + " ");
            a = b;
            b = c;
        }
    }
}

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🎯 4. Find Second Highest Number in Array

Company: TCS

Input: [2, 10, 5, 7]
Output: 7

public class SecondLargest {
    public static void main(String[] args) {
        int[] arr = {2, 10, 5, 7};
        int first = Integer.MIN_VALUE, second = Integer.MIN_VALUE;

        for (int num : arr) {
            if (num > first) {
                second = first;
                first = num;
            } else if (num > second && num != first) {
                second = num;
            }
        }

        System.out.println("Second largest: " + second);
    }
}

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✅ 5. Check if a String is Palindrome

Company: Cognizant

Input: "madam"
Output: true

public class PalindromeCheck {
    public static void main(String[] args) {
        String str = "madam";
        String reversed = new StringBuilder(str).reverse().toString();
        System.out.println(str.equals(reversed));
    }
}

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🧩 6. Print Pattern (Right Angled Triangle)

Company: TCS NQT

Input: 5
Output:
*
**
***
****
*****

public class TrianglePattern {
    public static void main(String[] args) {
        for (int i = 1; i <= 5; i++) {
            System.out.println("*".repeat(i));
        }
    }
}

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💡 7. Count Frequency of Each Character

Company: Infosys

Input: "apple"
Output:
a = 1
p = 2
l = 1
e = 1

import java.util.*;

public class CharFrequency {
    public static void main(String[] args) {
        String str = "apple";
        Map<Character, Integer> map = new LinkedHashMap<>();

        for (char c : str.toCharArray()) {
            map.put(c, map.getOrDefault(c, 0) + 1);
        }

        map.forEach((k, v) -> System.out.println(k + " = " + v));
    }
}

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📌 Conclusion

These questions are commonly asked during Java coding rounds for service-based and product-based companies. Practice writing clean and optimal solutions, and remember to explain your thought process during interviews.

Coming next: “Java Coding Round: Hard Level Challenges Asked in Product Companies”