How to create an ArrayList from array in Java? Example

One of the common problems faced by junior and less experienced Java develoeprs is converting an arrray to ArrayList e.g. they are getting an array from somewhere in their code and then want to create an ArrayList out of that, so that they can add more elements and use other library methods which operates with ArrayList or List. The simplest way to convert an array to ArrayList is by usign the Arrays.asList() method, which acts a bridge between Collection classes and array data structure. This method returns a List which contains elements from array.

Difference between Proxy and Decorator Pattern in Java

Though both Proxy and Decorator pattern looks very similar to each other structurally, there are some key differences between them. Main difference between Decorator and Proxy patterns comes from their Intent. Proxy word has a long standing meaning and in software world also a Proxy class stands for its implementation class, which presents lots of options to programmer, resulting in different kinds of proxy objects like remote proxy, virtual proxy, and protection proxy. On the other hand, Decorator pattern is used to add new functionality into existing object without modifying it's class. So their usage is entirely different.

Unix command to find IP address from hostname - Linux example

The IP address from hostname in UNIX
In this Unix command tutorial, we will see how to find the IP address of any host in a UNIX based system, like Linux, Solaris, or IBM AIX. In general hostname and IP address are two important things about any host in a UNIX based network.  You always need either a hostname or IP address to connect to any host. Sometimes you want to find the IP address of the localhost, sometimes the IP address of another host on the network, etc. We have shown some techniques to find the IP address from hostname in UNIX and here we will see is a particular list of UNIX commands to get the IP address of local host or host on which you are working along with any other host for which we know hostname.

How to find Files with Matching String in Linux? grep -l command Example

The grep command from Linux is one of the powerful commands to find files containing some text, but when you use grep, it not only print the file name but also the line, which is including the matching text. This is actually required and needed in most situations. Still, sometimes you only want to grep to show just filename and path and not the matching text. For example, when you are searching for some configurations like a Linux or database hostname across all configuration files in your application host, then you just want to see which file has contained those references.

6 Essential Data Structures Java Programmer should Learn

Hello guys, Data Structure is a building block of programs. It's even said that  "Data Structure + Algorithms= Program". That's why a good knowledge of data structure is very important for any programmers, including Java developers. Data structure gives you the option to store your data so that you can access it based on your requirement. For example, if you want a fast search based upon the username then you can use HashMap, but that's only possible if you know data structure and their implementations in the programming language you are using, and that's what you will learn in this article. 

How to prepare for Google Cloud Developer Certification exam? [Tips + Resources]

In the advent of an AI-based world, coding makes your life better both in terms of workplace and personal life. It helps you understand the developing world easier.  Every exam has its preparation strategy. Worthy things are never easy to get. One should put one's complete energy to clear what you want the most.  In this case, in the present day, this article is especially targeted to reach the hands of aspirants who wants to crack & possess the certificate of the most renowned exam. 


How to prepare for Google cloud developer exam


Before preparing for any exam, it's mandatory to know about the exam. In such a topic, the elements of the Google cloud developer exam is mandatory to take a look at. 

1. Is the Google cloud developer exam designated for you?

Google cloud developer exam is designated for anyone who wants to learn and for anyone interested in it. 

However, the Google cloud developer exam is specially designated for people who want to build, test, and deploy applications, managing and monitoring is performed. It is for people who have an undoubtedly quench to gain it.



2. All About Google cloud developer exam

The most prominent is

Duration of the exam: 2 hours

Exam fee: $200 (including all taxes)

Language: English and Japanese

Question format: multiple-choice questions

Total questions: 50

Prerequisite: none

Validity of the certificate: 2 years

Pass score: 80%

3. Why should you take Google cloud developer certification?

After all, why should you take this exam? What's the use of this certification? 

As Google puts it:

A Professional Cloud Developer builds scalable and highly available applications using Google-recommended practices and tools. This individual has experience with cloud-native applications, developer tools, managed services, and next-generation databases. A Professional Cloud Developer also has proficiency with at least one general-purpose programming language and is skilled at producing meaningful metrics and logs to debug and trace code.”

As Google puts it, it depicts how important this skill is, and for the further developing generations. It gives you a vibrational reputation in your work areas for sure. 

Moreover, 75% of IT and software companies need technically skilled employees, who can handle data, clouds immensely. 

For further acknowledgement, click on this link. 

Link: https://support.google.com/cloud-certification/answer/9437163?hl=en

4. What are the subjects to be covered in the Google cloud developer exam? 

Here's the syllabus, an important part.

• Designing APIs. 

• Securities

• Data management

• Building applications. 

To take a look at the complete syllabus, click on this link

Link: https://cloud.google.com/certification/guides/cloud-developer

5. Is the Google cloud developer exam tough? 

It's usual for freshers, who don't have any data engineering experience to get stuck with the hardness of the exam. 

Yet, Google offers you a lot of certification exams, firstly, you should pick up the right one for you. This would make the path a little easier. And, anyone can clear it for sure!

6. What do you need to crack the Google cloud developer exam?  

Whenever it comes to Google Cloud or AWS, people think that they must know complete coding to crack these exams. Yet, their thoughts are completely wrong. I've known friends of mine, who don't know the ABC of coding, and cleared the exam on the first try. 

Firstly, you don't need any software engineer or IT background. You just need to know - how coding works, how staging codes works, etc. Secondly, Google certifications are not a pick-and-go type. You should need to understand, memorize, and digest the topics. It's also important to learn practically, due to the case study format of the exams. Lastly, there Google has recommended having 3 years of experience to clear this exam, which isn't mandatory! All it takes is how you understand their concept and solve the problems. 


7. Start your Google cloud developer exam study: 

The common question on every mind of beginners is “where should I start?”. The starting problem is a big question mark. 

And to this question, this article will be a light to your path in guiding you through your journey. Google's examinations are one of the toughest exams of all time. This writing will be your handbook.

7.1. Online Course for Google cloud developer exam 

Get a qualified course that saves your time and interest than countless YouTube videos. A course is always crucial to teach you - what an aspect is about, reasons to learn it, ways to learn it, sectors of the profession, foundational bound explanation, practical application of theoretical points, bookish understanding into lab workshop. The course defines how and what your journey through the subject has to be. Presenting you three unshakable courses from top virtual teaching platforms.

#1 - Google Cloud Developer - GCP Professional Certification 

I've also taken off through the experience of being in the classes in GCP security engineer and cloud development, and I refer this course with my own experiences.

Link: https://www.udemy.com/course/google-cloud-certified-professional-cloud-developer/

#2 - Ultimate Google Certified Professional Cloud Developer 2020 

In 17 hours of on-demand video, you'll get to learn everything from comprehending this certification exam to security, privacy and observance. In every section, you'll get exam directions as bonus hits. 

Link: https://www.udemy.com/course/google-cloud-platform-professional-cloud-developer-certification/

#3 - Google Cloud Certified Professional Cloud Developer

Whizlabs  is a place where most of the certification training is best. I've heard from people who have cleared these exams to always recommend giving a glimpse of this site. Updated exam information with assessments, exam preparation tips, case studies, practical challenges in labs, machine learning, downloadable resources, and so on... Phew! What else can I say about this course?! No words to enunciate it. The educator's theoretical points nail the words in your hearts. It has video courses and also practice tests.

Link: https://www.whizlabs.com/google-cloud-certified-professional-cloud-developer/

7.2. Publications for Google cloud developer exam

Just watching the videos and getting into the exam hall with the mindset that you'll clear it in no time isn't the right thought. It takes a lot of knowledge, especially from books. 

#1 - Google Cloud Platform for Developers 

Link: https://www.amazon.in/Google-Cloud-Platform-Developers-solutions/dp/1788837673


#2 - Google Certified Professional Cloud Developer: Exam Cram Notes

Link: https://www.amazon.in/Google-Certified-Professional-Cloud-Developer-ebook/dp/B09K42VP5J/


#3 - Google Cloud Certified Professional Cloud Developer Exam Guide: Modernize your applications using cloud-native services and best practices

Link: https://www.amazon.in/Google-Cloud-Certified-Professional-Developer/dp/1800560990/


7.3. Additional Resources for Google Cloud Platform for Developers 

Here are cheatsheets, whitepapers, blogs that are very useful in preparing for the exam. 

• Cheatsheet of GitHub is very promising and also revamps the updated version of the exam. 

Link https://github.com/priyankavergadia/google-cloud-4-words

• Whitepapers are better ones and worth spending your spare time in it. Here are the whitepapers from the official site, which would give an idea. 

Link: https://cloud.google.com/whitepapers


7.4. Best Simulators for Google cloud developer exam  

Now, it's time for the test! Simulators are nothing but a series of practice tests to check your theory grasping power. It also helps you in time management by managing your time in the given period of hours. You must work on practice examinations before you encounter the real one. 

Here are some great series, which were helpful for me. 

• Find instant practice exam questions, tools and study materials. It has 138 outstanding questions with answers for free. 

Link: https://www.google.com/amp/s/www.certification-questions.com/amp/google-exam/professional-cloud-developer-dumps.html

• Google Cloud Professional Cloud Developer Practice Test. Comprises 117 questions with detailed explanations and reference links. 

Link: https://www.udemy.com/course/google-cloud-professional-cloud-developer-practice-test/

• GCP: Professional Google Cloud Developer Practice Test with 41 backbreaking questions. 

Link: https://www.udemy.com/course/gcp-professional-google-cloud-developer-practice-test/

Make sure you Practice these tests and quizzes wisely. You must score 90% in the practice tests to crack the real one. 


7.5. Official Practice Sessions

Link https://docs.google.com/forms/d/e/1FAIpQLSfFeB8zBNi2q-ar0V7iIguhk2e6P-UkrJ8OJfg6n0k6HcYLDQ/viewform

You've to fill the form to take an official practice test, yet it's free. It's from the official Google Cloud page. It has a few questions which all are equal to the exam point of view. It's something like a mini-exam. I hope there were surplus questions in this. 

8. Common Doubts in Google Cloud Platform for Developer Exam

Doubts of registration, doubts in learning part, doubt in syllabus, and doubts in this, doubts in that, doubts doubts doubts. Every beginner's brain is flooded with so many questions when it comes to examination. 

Understanding your mind, Google has attached a FAQ part to its official page to clear all your doubts. You can view it just by clicking this link. 

Link: https://support.google.com/cloud-certification/#topic=9433215

You can just visit that site, describe your issue, and clear your doubts & queries. 

Wrapping up: 

The Google cloud developer exam has a wide range of applications in both terms of machine learning and data science. Hence, this certification adds color to your CV and to your life in acquiring your desired pay-check digit. 

How to Find Missing Number in a Sorted Array in Java [Solved]

Today's coding problem is not very new, it's an age-old classic Programming interview Question. You have a sorted array containing n - 1 unique number starting from 0 to n - 1. There is only one number missing in this range and you need to find that out. I mean you need to write a Java method to find the missing number and print its value in the console. Some of you might have seen this question before, but if you have not been asked this question before, what is the first approach comes into your mind to solve this question? Since only one number is missing, many programmers come up with the approach of iterating over the array, and comparing each element with the expected one like the first element should be 0, the second element should be 1, and so on.

13 Java Serialization Interview Questions with Answers for 3 to 5 Years Experienced

There is no doubt that Java is vast and there are some Java topics which many Java developers rarely explore in work but they are important from a Java interview point of view. Serialization is one of them which is rarely used in practice but quite popular during Java interviews. It's also one of the difficult topics to master and that's why I am going to share some frequently asked Java Serialization interview questions in this article.  I don't know why people ask so many questions from Serialization if not everyone uses it but I have always seen some questions from Java realization. These are also the toughest and confusing questions to answer and more likely cannot be answered by an average Java developer.

6 Best Free AZ-900 Azure Fundamentals Courses for Beginners to Learn Online in 2024

Hello guys, if you are preparing for the AZ-900 certification or Azure Fundamentals exam in 2024, one of the best certifications to start a cloud computing career, and looking for free online courses to start your preparation, then you have come to the right place. In the past, I have shared both free and paid courses to learn AWS, Azure, and Google Cloud and the best AZ-900 courses and practice tests, and today, I am going to share the best free AZ-900 courses to pass the Azure Fundamentals exam. If you are thinking of learning Cloud Computing and Microsoft Azure platform, this is the best cloud certification. 

10 Regular Expressions Every Java Programmer Should Learn

Regular Expression or regex or regexp is used for String or text matching. You specify a regular expression and then run input String to see if any String matches with your regular expression. There are a lot of use cases of regular expression e.g. you can do find and replace and you can actually search in a big log file for the expression or text you are looking it. Regular expression is not just limited to any programming language like Java but it present everywhere. You use Regular expression in Linux for pattern matching like with grep, find, sed and awk command. Even VI editor allows you to search words using regular expression and popular Windows text editor like Notepad++ and Edit Plus they also support regular expression for search and replace.

Top 70 Java Interview Questions for Junior Developers [1 to 2 Years Experienced]

Java Developer Interviews are very different than traditional software developer interviews. You can clear a Java interview without even writing a single line of code, Yes, this is true, you can become a Java developer without someone asking you to write a function in a Java interview. Though it's not the case everywhere and many companies are increasingly including a coding test in their Java developer interview process, but there are many companies and start-ups where you can get a Java job without writing a single line of code. All you need to do is learn those popular Java questions, which have been asked for ages, and mostly test whether a candidate is familiar with essential Java concepts or not like abstract class and interface. 

Top 5 Free JavaScript Books for Beginners - Download PDF or Read Online

The internet is full of good things, and one of them is free eBooks and PDF. Programmers can almost run anything by these free books. Earlier I have shared some of the free JavaScript tutorials, and in this article, I am going to share 5 good books to learn JavaScript, which are open to read online or allow you to download PDF for offline reading. JavaScript is probably another language I recommend someone who knows Java, Why? Because it's really ubiquitous. There is almost no website that is not using JavaScript in one or another format.

Difference between Set, List and Map in Java - Interview question

Set, List and Map are three important interfaces of the Java collection framework, and the difference between Set, List, and Map in Java is one of the most frequently asked Java Collection interview questions. Sometimes this question is asked as When to use List, Set and Map in Java. Clearly, the interviewer is looking to know that whether you are familiar with the fundamentals of the Java collection framework or not. In order to decide when to use List, Set or Map, you need to know what are these interfaces and what functionality they provide. List in Java provides ordered and indexed collection which may contain duplicates. 

Difference between Heap and Stack Memory in Java? [Explained]

One of the many traits of a good programmer is how well he understands the fundamentals and if you want to check the fundamentals of a Java programmer then asking the difference between heap and stack memory is a good choice. Even though both are part of JVM and both consumer's memory allocated to the Java process, there are many differences between them like Heap memory is shared by all threads of Java application but Stack memory is local to each thread. Objects are created in heap memory but method frames are stored in Stack memory, and the size of heap space is much bigger than the small size of Stack in Java.

Top 80 Core Java Interview Questions with Answers

Hey Java programmers, if you are preparing for a Core Java interview and looking for some frequently asked Java interview questions for quick revision then you have come to the right place. Earlier, I have shared the best books and best courses for Java interviews.  I have also shared many posts about Java Interview Questions and in this article, I will share Java Interview questions and answers especially for junior Java programmers, someone with 1 to 3 years of experience. This includes college graduates, who are looking for the job, Java programmers who have 1 to 2 years of experience in Java, and junior developers who have 2 to 3 years of experience in Java, C++, etc. 

10 Free Java Programing Books for beginners - download, pdf and HTML

Every Java programmer loves free eBooks on Java, don't you? When I shared my collection of top 10 Java programming books, one of my readers asked me to share some free Java books as well. Doing a quick search on the internet reveals lots of free books, resources, and tutorials to learn Java. I have chosen some of the good Java books, which are FREE, available for download or you can read it online in HTML or PDF format. These books are an excellent resource for any Java beginners, as well as an experienced programmer, and since they are free, it makes absolute sense to have a look on this before buying any other book in Java.

Top 5 Free Courses to Learn NFT (Non Fungible Tokens) - Best of Lot

Hello folks, if you want to learn about NFT in 2022 or want to create and sell your own NFT and looking for free resources then you have come to the right place. Earlier, I have shared the best Blockchain coursesbest Ethereum Courses, and best courses to learn NFT (Non-Fungible Tokens), but a lot but then many of you ask for free courses and I decided to put together a list of the best free NFT courses you can join to learn everything about NFT, create Non Fungible tokens and sell them on different platforms like OpenSea. Before we get into the best free courses that you can use to learn more about NFT, you need to know the basics.

How does Hello world program in Java works? Example and Explanation

When I first started with Java programming, the first program I wrote was HelloWorld in Java. That time I just copied it from a textbook we were referring to, I didn't know anything about it. It took me a lot of time to understand everything about HelloWorld in Java and how it works. From that time, I made it a rule to start with writing the HelloWorld program in any new programming language I learn and try to understand every single element of it in as much detail as possible, but,  to be frank, its not that easy. 

How to Create, Start, and Stop a New Thread in Java? [Example Tutorial]

One of the most important tasks for a Java developer is to learn multi-threading and learn it correctly. There are more Java developers who know multi-threading incorrectly than the programmer who doesn't know at all. In order to learn it correctly, you need to start it from scratch, means the most fundamental concepts of multithreading like how to create create, start, and stop a new thread in Java. I am sure you already know that as you have done that a lot of time but it's worth remembering few facts to not repeat the mistakes many programmers do when they write multithreading code in Java. 

How to use CountDownLatch in Java? Example

CountDowaLatch is a high-level synchronization utility that is used to prevent a particular thread to start processing until all threads are ready. This is achieved by a countdown. The thread, which needs to wait for starts with a counter, each thread make the count down by 1 when they become ready, once the last thread call countDown() method, then the latch is broken and the thread waiting with the counter starts running. CountDownLatch is a useful synchronizer and is used heavily in multi-threaded testing.

How to sort a List or Stream by Multiple Fields in Java? Comparator comparing() + thenComparing Example

One of the common requirements in Java is to compare objects by multiple fields. For example, if you have a list of CreditCard objects and you want to compare them by their provider and credit limit I mean, first compare them by their providers like VISA, Master, or American Express and if they are from the same provider then compare them by their credit limit, also known as breaking ties. Before Java 8 this wasn't easy because you have to write nested codes to compare multiple fields of an object as there was no easy way to chain multiple Comparators in Java, but things have changed a lot from Java 8.

How to use CompletableFuture in Java? Example Tutorial

Hello friends, we meet again today on our journey to Java. So I hope you guys are excited about this Java concurrency lesson. Let me ask you guys one thing before we proceed. Do you guys ever wonder about the future? At some point in time, all of you must have thought about it and wondered about different kinds of outcomes. Well, our Java program also wonders about its future tasks so, let us learn today something similar to that! First of all, before jumping onto what a CompletableFuture is, let us first know what a Future in Java is? For guys who know this beforehand, just refresh the concept and for everyone else, let’s understand what it is.

How to Print Floyd's Triangle in Java - Example Tutorial

Hello guys, In the last article, I have taught you how to print Pascal's triangle and in today's article, I'll teach you how to print Floyd's triangle in the Java program. Floyd's triangle is easier to print than Pascal's triangle because you don't need to take care of formatting the numbers as Floyd's triangle is a right-angle triangle. It is named after American computer scientist Robert Floyd, who has also contributed Floyd–Warshall algorithm, which efficiently finds all shortest paths in a graph, and Floyd's cycle-finding algorithm for detecting cycles in a sequence. 

Matrix Multiplication in Java using Scanner, Class, and Function [Example]

Hello guys, if you are looking for a matrix multiplication example in Java using the scanner for user input, and using class and object-oriented programming then you have come to the right place. In this Java tutorial, I will show you how to multiply matrix in Java using an array, scanner, and object-oriented programming. We will create a class to represent matrix and then define a multiplication method to multiply two matrices in Java. I first learned about matrix in class 12th and I first wrote the program to multiply two matrices on my first semester of engineering, so, when I thought about this program, It brings a lot of memories from the past. 

How to Count number of 1s (Set Bits) in a binary number in Java [Solved]

Good morning folks, In today's article, we are going to discuss one of the frequently asked bit manipulation-based interview questions, how do you count the number of set bits in a given bit sequence?  Bit Manipulation is an important topic in programming interviews and a good programmer should have sufficient knowledge and skill to work with binary numbers. This kind of question tests the skill of the programmer. Sometimes, it is also asked as to how to count the number of 1s (ones) in a given number? Both are the same question because 1 is also known as set bit.  For example, if the given input is 1000110010 then your program should return 4, as three are only four set bits in this bit sequence.

3 ways to Find Duplicate Elements in a given Array in Java [Solved]

Hello guys, if you are wondering how to find duplicates from a given array in Java then you have come to the right place. This is one of the most popular coding problems from interviews and there are multiple ways to solve this problem. In this article, I will show you three ways to solve this problem. First, you will learn how to solve the problem using brute force way and then you will see how you can optimize and simplify the solution by using additional memory and using an appropriate data structure like a HashSet or Hash table. In the real interview, you may need to solve this problem in some constraints like you cannot use additional memory or additional data structure that's where knowing multiple ways to find duplicate in Java array really help.

Top 7 Free Selenium Courses for Beginners to Learn Online in 2024 - Best of Lot

Testing is an integral part of software development. We have long relied on manual testing by testers and QA professionals to ship quality software and find bugs, but that's not sustainable anymore. There is an increased focus on automation testing nowadays, and Selenium is leading its web drivers. If you don't know Selenium, it's a free automation testing tool for web applications. It can work with different web browsers like Chrome, Firefox, Internet Explorer, and Opera and simulate human-like behavior. Using Selenium, you can programmatically interact with all the other elements on a webpage. You can click on them, input text, extract text, and more.

How to get the value of a checkbox using jQuery ? Example Tutorial

Suppose you have a web page with a checkbox like a registration page where you have a checkbox about reading terms and conditions. When the user clicks the submit button, your job is to validate whether that particular checkbox is checked or not? How do you do that? How do you get the value of the checkbox to see if it's checked or not? Well, you can use a pseudo-selector ":checked" to see if that checkbox is checked or not. This selector returns true if the user has clicked and kept the checkbox checked; false otherwise. You can get the checkbox either by class or id and then you can call the is(":checked") method, as shown in our example. 

How to convert an int to String in Java? 4 Examples Tutorial

Hello guys, if you new to Java programming and wondering how to convert an int to a String object in Java then don't worry, you have come to the right place. Earlier, I have shown you how to convert an Integer to a String and in this article, I will show you how to convert an int variable to a String in Java. The difference between an Integer and an int is that the former is an object while an int variable is a primitive value. You can use the String.valueOf() or Integer.toString() method to convert an int value to a String object in Java. Remember, String is not just a char array but a full feature object in Java. 

Post order traversal Algorithms for Binary Tree in Java with example

In the last couple of articles, you have learned about pre-order and in-order tree traversal algorithms in Java, and today, you will learn about the post-order traversal in a binary tree. It is the toughest of all three tree traversal algorithms and programmers generally struggle to implement this when asked in a coding interview. Hence it makes sense to understand and practice this algorithm before going for the interview. The post order traversal is also a depth-first algorithm because you go deep before you visit other nodes on the same level.

Top 5 Computer Vision and OpenCV Courses to Learn in 2024 - Best of Lot

Hello guys, if you want to learn Computer Vision and OpenCV and look for the best computer vision online courses from Udemy, Coursera, and Pluralsight, you have come to the right place. Earlier, I have shared the best online courses to learn Python, Data Science, and Machine Learning from Coursera and Udemy, and in this article, I am going to share the best online training courses to learn both Computer Vision and OpenCV. The list includes courses for beginners and experienced programmers who want to learn the advanced concept of Computer Vision and Open CV.  It's one of the most existing fields of Machine Learning and Artificial Intelligence and has uses across industries like object detection, self-driving cars, robotics, and much more.

5 Free Courses for Google Cloud Professional Architect Certification [2024] - Best of Lot

Hello guys, if you are preparing for Google Cloud Professional Architect certification and looking for free online training courses, you have come to the right place. In the past, I have shared the best courses to learn Google Cloud and certification courses to pass cloud engineer, data engineer, and cloud architect certifications. Today, I will share free GCP Cloud Architect certification courses for beginners experienced cloud professionals. This is one of the most difficult and prestigious exams, similar ot the AWS Solution Architect and Azure Technology Architect (AZ-300) exam; once you pass this exam, you will have sufficient knowledge and skills to propose a Google cloud-based solution in-demand skill.