Abdultaiyeb Siyamwala’s Post

QA Knowledge: Most imp Java interview question. 𝗤𝘂𝗲𝘀𝘁𝗶𝗼𝗻: 𝗖𝗮𝗻 𝘄𝗲 𝗼𝘃𝗲𝗿𝗹𝗼𝗮𝗱 𝗮 𝗺𝗮𝗶𝗻() 𝗺𝗲𝘁𝗵𝗼𝗱 𝗶𝗻 𝗝𝗮𝘃𝗮? 𝗔𝗻𝘀𝘄𝗲𝗿: Yes, we can overload the `main()` method in Java. Overloading means defining multiple methods with the same name but different parameters. In Java, the main() method has the following signature: 𝗽𝘂𝗯𝗹𝗶𝗰 𝘀𝘁𝗮𝘁𝗶𝗰 𝘃𝗼𝗶𝗱 𝗺𝗮𝗶𝗻(𝗦𝘁𝗿𝗶𝗻𝗴[] 𝗮𝗿𝗴𝘀) You can create other methods with the same name but different parameter lists. For example: 𝐩𝐮𝐛𝐥𝐢𝐜 𝐜𝐥𝐚𝐬𝐬 𝐌𝐚𝐢𝐧𝐎𝐯𝐞𝐫𝐥𝐨𝐚𝐝 {   𝐩𝐮𝐛𝐥𝐢𝐜 𝐬𝐭𝐚𝐭𝐢𝐜 𝐯𝐨𝐢𝐝 𝐦𝐚𝐢𝐧(𝐒𝐭𝐫𝐢𝐧𝐠[] 𝐚𝐫𝐠𝐬) {     𝐒𝐲𝐬𝐭𝐞𝐦.𝐨𝐮𝐭.𝐩𝐫𝐢𝐧𝐭𝐥𝐧("𝐌𝐚𝐢𝐧 𝐰𝐢𝐭𝐡 𝐒𝐭𝐫𝐢𝐧𝐠[] 𝐚𝐫𝐠𝐬");     𝐦𝐚𝐢𝐧(𝟏); // 𝐂𝐚𝐥𝐥𝐢𝐧𝐠 𝐨𝐯𝐞𝐫𝐥𝐨𝐚𝐝𝐞𝐝 𝐦𝐚𝐢𝐧   }       𝐩𝐮𝐛𝐥𝐢𝐜 𝐬𝐭𝐚𝐭𝐢𝐜 𝐯𝐨𝐢𝐝 𝐦𝐚𝐢𝐧(𝐢𝐧𝐭 𝐧𝐮𝐦) {     𝐒𝐲𝐬𝐭𝐞𝐦.𝐨𝐮𝐭.𝐩𝐫𝐢𝐧𝐭𝐥𝐧("𝐎𝐯𝐞𝐫𝐥𝐨𝐚𝐝𝐞𝐝 𝐦𝐚𝐢𝐧 𝐰𝐢𝐭𝐡 𝐢𝐧𝐭: " + 𝐧𝐮𝐦);   }    𝐩𝐮𝐛𝐥𝐢𝐜 𝐬𝐭𝐚𝐭𝐢𝐜 𝐯𝐨𝐢𝐝 𝐦𝐚𝐢𝐧(𝐒𝐭𝐫𝐢𝐧𝐠 𝐚𝐫𝐠𝟏, 𝐒𝐭𝐫𝐢𝐧𝐠 𝐚𝐫𝐠𝟐) {     𝐒𝐲𝐬𝐭𝐞𝐦.𝐨𝐮𝐭.𝐩𝐫𝐢𝐧𝐭𝐥𝐧("𝐎𝐯𝐞𝐫𝐥𝐨𝐚𝐝𝐞𝐝 𝐦𝐚𝐢𝐧 𝐰𝐢𝐭𝐡 𝐭𝐰𝐨 𝐒𝐭𝐫𝐢𝐧𝐠𝐬: " + 𝐚𝐫𝐠𝟏 + ", " + 𝐚𝐫𝐠𝟐);   } } **𝗡𝗼𝘁𝗲: In this example, the `main()` method is overloaded with different parameter lists. However, the Java runtime only calls the main() method with the signature `𝗽𝘂𝗯𝗹𝗶𝗰 𝘀𝘁𝗮𝘁𝗶𝗰 𝘃𝗼𝗶𝗱 𝗺𝗮𝗶𝗻(𝗦𝘁𝗿𝗶𝗻𝗴[] 𝗮𝗿𝗴𝘀)` as the entry point for the application.

QA Knowledge: Java interview question. 𝐐𝐮𝐞𝐬𝐭𝐢𝐨𝐧: 𝐖𝐫𝐢𝐭𝐞 𝐚 𝐉𝐚𝐯𝐚 𝐩𝐫𝐨𝐠𝐫𝐚𝐦 𝐭𝐨 𝐝𝐞𝐭𝐞𝐫𝐦𝐢𝐧𝐞 𝐢𝐟 𝐚 𝐠𝐢𝐯𝐞𝐧 𝐒𝐭𝐫𝐢𝐧𝐠 𝐢𝐬 𝐚 𝐩𝐚𝐥𝐢𝐧𝐝𝐫𝐨𝐦𝐞. Answer: A palindrome is a string that reads the same forward and backward. For example, "𝐫𝐚𝐝𝐚𝐫" 𝐢𝐬 𝐚 𝐩𝐚𝐥𝐢𝐧𝐝𝐫𝐨𝐦𝐞, 𝐛𝐮𝐭 "𝐡𝐞𝐥𝐥𝐨" 𝐢𝐬 𝐧𝐨𝐭. github code: https://lnkd.in/dv86uguh 𝐂𝐨𝐝𝐞 𝐄𝐱𝐩𝐥𝐚𝐧𝐚𝐭𝐢𝐨𝐧: The program reads a string from the user. It converts the string to lowercase to ensure the check is case-insensitive. It reverses the string by iterating over it backward. The original string is compared with the reversed string to determine if it is a palindrome.

QA- most common java interview question Question: How can you remove junk or special characters from a string in Java? Answer: To remove junk or special characters from a string in Java, you can use the `replaceAll` method with a regular expression (regex). The regex pattern can match any character that is not a letter or a digit, and you can replace those characters with an empty string. Code Link: https://lnkd.in/dmqV5yxK Code Explanation: 1. Initialize the String: The `original` string contains the input with special characters. 2. Regex Pattern: The pattern `[^a-zA-Z0-9]` matches any character that is not a lowercase letter `(a-z)`, an uppercase letter `(A-Z)`, or a digit `(0-9)`. 3. Replace All: The `replaceAll` method replaces all characters that match the pattern with an empty string `""`, effectively removing them from the string. 4. Output: Finally, the program prints both the original and the cleaned strings.

QA Knowledge- Java Coding Interview Questions Question: Write a Java program to input name, middle name and surname of a person and print only the initials. Answer: Here's a Java program that takes the first name, middle name, and surname of a person as input and prints only the initials: github Code link: https://lnkd.in/dvGkpycm ✅ How the Program Works: 1️⃣ Input: The program prompts the user to enter their first name, middle name, and surname. It uses the Scanner class to read input from the console. 2️⃣ Trimming Input: The trim() method is used to remove any leading or trailing spaces from the input. 3️⃣ Getting Initials: The `getInitial()` method is defined to extract the first letter of each name and convert it to uppercase. If the user provides an empty string (e.g., no middle name), the method handles it by returning an empty string, avoiding any errors. 4️⃣ Output: The program prints the initials, each followed by a period (.).

18 Mostly Used Java List Methods for QA during Interview Here are 18 most used methods that you should know: 1. add(E element) - Adds the specified element to the end of the list. 2. addAll(Collection<? extends E> c) - Adds all elements of the specified collection to the end of the list. 3. remove(Object o) - Removes the first occurrence of the specified element from the list. 4. remove(int index) - Removes the element at the specified position in the list. 5. get(int index) - Returns the element at the specified position in the list. 6. set(int index, E element) - Replace the element at the specified position in the list with the specified element. 7. indexOf(Object o) - Returns the index of the first occurrence of the specified element in the list. 8. contains(Object o) - Returns true if the list contains the specified element. 9. size() - Returns the number of elements in the list. 10. isEmpty() - Returns true if the list contains no elements. 11. clear() - Removes all elements from the list. 12. toArray() - Returns an array containing all the elements in the list. 13. subList(int fromIndex, int toIndex) - Returns a view of the portion of the list between the specified fromIndex, inclusive, and toIndex, exclusive. 14. addAll(int index, Collection<? extends E> c) - Inserts all elements of the specified collection into the list, starting at the specified position. 15. iterator() - Returns an iterator over the elements in the list. 16. sort(Comparator<? super E> c) - Sorts the elements of the list according to the specified comparator. 17. replaceAll(UnaryOperator<E> operator) - Replaces each element of the list with the result of applying the given operator. 18. forEach(Consumer<? super E> action) - Performs the given action for each element of the list until all elements have been processed or the action throws an exception. LinkedIn Guide to Creating

Java important questions

🌟🔍🔥 Exciting News! 🌟🔍🔥 Are you ready to master the world of Java interviews? 🚀🔥 Let's dive into the top core Java interview questions and answers together! 💻📚 🧠💡 Prepare yourself for the ultimate coding adventure and get ready to impress recruiters with your Java skills! 💪🌟 🔎💼 Discover the secrets to acing Java interviews with confidence and ease. 🎯🔐 🔍📚 From basic concepts like object-oriented programming and data types to advanced topics like multithreading and exception handling, we've got you covered! 😉📖 🔥🔥 Don't miss out on this golden opportunity to level up your Java game! Whether you're a fresh graduate, a seasoned professional, or someone looking to switch careers, mastering these core Java interview questions is essential for your success. Here's a sneak peek at some popular Java interview questions and their answers, sprinkled with emojis and hashtags to make learning more fun and engaging! 🌟💡 1️⃣ Question: What is the difference between JDK, JRE, and JVM? 🤔 🔑 Answer: JDK (Java Development Kit) is a software development environment that includes the JRE (Java Runtime Environment) as well as tools and libraries to develop Java applications. JRE is the runtime environment that is needed to run Java applications. JVM (Java Virtual Machine) is the virtual machine that executes Java bytecode. 2️⃣ Question: What is the difference between ArrayList and LinkedList in Java? 🤔 🔑 Answer: ArrayList is implemented as a resizable array, while LinkedList is implemented as a doubly-linked list. ArrayList provides fast random access and is suitable for frequent element access and modification. LinkedList provides fast insertion and deletion in the middle of the list. 3️⃣ Question: What is the purpose of the 'final' keyword in Java? 🤔 🔑 Answer: The 'final' keyword can be used to define constants, prevent method overriding, and make a class or method uninheritable. It ensures that the value of a variable doesn't change, the implementation of a method cannot be changed, or a class cannot be extended. 4️⃣ Question: Explain the concept of multithreading in Java. 🤔 🔑 Answer: Multithreading is the ability of a CPU to execute multiple threads concurrently. In Java, threads allow multiple tasks to run concurrently within a single program. It enhances performance by utilizing the available CPU resources efficiently. 🌟✨ Keep exploring and mastering these core Java interview questions to boost your confidence and stand out in your next job interview! Remember to practice coding, review relevant Java concepts, and stay up-to-date with the latest industry trends. 📚📈 👉 Stay tuned for more valuable Java interview tips and tricks coming your way! 🎉 🌟✨ Let's conquer the Java interview world together! Join the conversation and share your favorite Java interview question using emojis below! 👇💬 #JavaInterviewsRock #JavaEnthusiasts #CodeGeeksUnite 🚀🔥 Follow me 👉🏻 Pratham Pathak for more amazing content 🔥 !!

important core Java interview questions

🌟 **Top Array Interview Questions in Java Explained** 🌟 Hello LinkedIn Community! Arrays are a crucial topic in Java interviews. Here are some top questions and their explanations to help you prepare: 1. How do you find the missing number in an array of 1 to N? int sum = (n * (n + 1)) / 2; for (int num : array) { sum -= num; } return sum; Explanation: Calculate the expected sum of numbers from 1 to N and subtract each array element from this sum to find the missing number. 2. How do you find the largest and smallest number in an array? int max = array[0]; int min = array[0]; for (int num : array) { if (num > max) max = num; if (num < min) min = num; } Explanation: Traverse the array, comparing each element to the current max and min values to find the largest and smallest numbers. 3. How do you reverse an array in place? int left = 0, right = array.length - 1; while (left < right) { int temp = array[left]; array[left] = array[right]; array[right] = temp; left++; right--; } Explanation: Use two pointers, swapping elements from the start and end until they meet in the middle. 4. How do you remove duplicates from a sorted array? int[] temp = new int[array.length]; int j = 0; for (int i = 0; i < array.length - 1; i++) { if (array[i] != array[i + 1]) { temp[j++] = array[i]; } } temp[j++] = array[array.length - 1]; Explanation: Traverse the sorted array, adding unique elements to a temporary array. 5. How do you find the intersection of two arrays? Set<Integer> set = new HashSet<>(); for (int num : array1) { set.add(num); } for (int num : array2) { if (set.contains(num)) { // num is in both arrays } } Explanation: Use a HashSet to store elements of the first array and check for common elements in the second array. Mastering these array concepts will help you excel in your next Java interview. Happy coding and best of luck! 💻🚀 #Java #Programming #Arrays #InterviewPreparation #TechTips #Coding

Java QA Knowledge Question: how to find smallest and largest number in an array? Answer: Here's how to find the largest and smallest numbers in an array using the given Java code, along with a detailed explanation: Code Link: https://lnkd.in/dFPYUaP8 Code Explanation: 1. Array Initialization*: - `int numbers[] = {-10, 24, 50, -88, 4656};` - An integer array named `numbers` is initialized with sample values: `{-10, 24, 50, -88, 4656}`. 2. Initial Variable Setup: - `int largest = numbers[0];` - The variable `largest` is initialized with the first element of the array (`numbers[0]`). - `int smallest = numbers[0];` - The variable `smallest` is initialized with the first element of the array (`numbers[0]`). 3. Iteration Through the Array: - `for (int i = 1; i < numbers.length; i++) { ... }` - A `for` loop is used to iterate through the array starting from the second element (`i = 1`) to the last element (`i < numbers.length`). 4. Finding the Largest Number: - `if (numbers[i] > largest) { largest = numbers[i]; }` - Inside the loop, an `if` statement checks if the current element (`numbers[i]`) is greater than the current value of `largest`. - If true, `largest` is updated to the current element (`numbers[i]`). 5. Finding the Smallest Number: - `else if (numbers[i] < smallest) { smallest = numbers[i]; }` - An `else if` statement checks if the current element (`numbers[i]`) is smaller than the current value of `smallest`. - If true, `smallest` is updated to the current element (`numbers[i]`). 6. Printing the Results**: - `System.out.println("Largest number is: " + largest);` - This line prints the largest number found in the array. - `System.out.println("Smallest number is: " + smallest);` - This line prints the smallest number found in the array.