How to parse String to LocalDate in Java 8 - DateTimeFormatter Example

From Java 8 onward, you are no longer dependent on the buggy and bulky SimpleDateFormat class to parse and format date Strings into real Date objects in Java e.g. java.util.Date. You can use the DateTimeFormatter class from java.time package for all your formatting and parsing need. You are also no longer required to use another buggy class java.util.Date if you are doing fresh development, but if you have to support legacy code then you can also easily convert LocalDate and LocalTime to java.util.Date or java.sql.Date. In this tutorial, we will learn about both parsing String to date in Java and formatting Date into String.

How to Convert String to LocalDateTime in Java 8 - Example Tutorial

Hello guys, today, I will talk about a common problem while working in a Java application, yes you guessed it right, I am talking about String to Date conversion in Java. I had discussed this before (see the Date to String) when Java 8 was not out, but with Java 8, I don't see any reason to use old date and time API, and hence I am writing this post to teach you how to convert String to Date in Java 8 or beyond. Suppose you have a date-time String "2016-03-04: 11:01:20" and you want to convert this into a LocalDateTime object of Java 8 new date and time API, how do you do that? Well, if you have worked previously with String and Date then you know that you can parse String to Date in Java.

How to Calculate Next Date and Year in Java? LocalDate and MonthDay Example Tutorial

Hello guys, if you are wondering how to calculate the next premium date, next birthday, or exact date for the next Christmas holiday in Java then you have come to the right place. Earlier, I have shared 20+ examples of Date and Time in Java, and in this article, I will show you how you can use the LocalDate and MonthDay class from the new Java 8 Date and Time package to calculate the next or previous date in Java. This new API is very well structured and you have classes to represent different Date concepts, for example, you can use LocalDate to represent a Date without time components like the next premium date or employee joining date or birth date.

How to find difference between two dates in Java 8? Example Tutorial

One of the most common programming task while working with date and time objects are calculating the difference between dates and finding a number of days, months, or years between two dates. You can use the Calendar class in Java to get days, months between two dates. The easiest way to calculate the difference between two dates is by calculating milliseconds between them by converting java.util.Date to milliseconds using the getTime() method. The catch is converting those milliseconds into Days, Months and Year is not tricky due to leap years, the different number of days in months, and daylight saving times.

How to get current Day, Month, Year from Date in Java? LocalDate vs java.util.Date Example

In this article, I'll show you how to get the current day, month, year, and dayOfWeek in Java 8 and earlier version like Java 6 and JDK 1.7. Prior to Java 8, you can use the Calendar class to get the various attribute from java.util.Date in Java. The Calendar class provides a get() method which accepts an integer field corresponding to the attribute you want to extract and return the value of the field from the given Date, as shown here. You might be wondering, why not use the getMonth() and getYear() method of java.util.Date itself, well, they are deprecated and can be removed in the future version, hence it is not advised to use them.

How to convert Timestamp to Date in Java?JDBC Example Tutorial

In the last article, I have shown you how to convert Date to Timestamp in Java and today we'll learn about converting timestamp value from database to Date in Java. As you remember, the JDBC API uses separate Date, Time, and Timestamp classes to confirm DATE, TIME, and DATETIME data type from the database, but most of the Java object-oriented code is written in java.util.Date. This means you need to know how to convert the timestamp to date and vice-versa. You can do by using the getTime() method, which returns the number of millisecond from Epoch value.

Difference between ServletConfig and ServletContext in JSP Servlet? Answer

Difference between ServletConfig and ServletContext

ServletContext and ServletConfig these two are the important interface of Servlet API which is used by Java J2EE programmer during web application development. Correct understanding of What is ServletContext and ServletConfig is very important for any J2EE application developer. Apart from that Difference between ServletContext and ServletConfig are a popular Servlet JSP interview questions and mostly asked on both fresher and experienced Java programmer during J2EE interviews.

How to create and initialize List or ArrayList in one line in Java? Example

creating and initializing List at the same time

Sometimes we want to create and initialize a List like ArrayList or LinkedList in one line much like creating an array and initializing it on the same line. If you look at The array on Java programming language you can create and initialize both primitive and object arrays e.g. String array very easily in just one line but in order to create a List equivalent of that array, you need to type a lot of code. This is also one of the tricky Java question sometimes appears in Interview as Write Java code to create and initialize ArrayList in the same line.

Difference between include directive, include action and JSTL import tag in JSP? Answer

There are three main ways to include the content of one JSP into another:

include directive

JSP include action

and JSTL import tag

The include directive provides static inclusion. It adds the content of the resource specified by its file attribute, which could be HTML, JSP, or any other resource at translation time.

Any change you make in the file to be included after JSP is translated will not be picked up by the include directive.

Difference between UNION vs UNION ALL in SQL? Example

Hello guys, what is the difference between UNION vs UNION ALL is one of the most popular SQL interview questions and often asked programmers during a telephonic round of interviews. Though both UNION and UNION ALL is used to combine results of two SELECT queries, the main difference between them is that UNION doesn't include duplicate record but UNION ALL does. Another difference between them is that UNION ALL is faster than UNION but may look slow because it returns more data which takes more time to travel via the network. The difference between UNION and UNION ALL can be a tricky SQL question, especially for developers, who have not used this useful keyword ever.

Can you join two unrelated tables in SQL? Cross Join Example

In one of the recent programming job interviews, one of my readers was asked the question, how do you join two tables which are not related to each other? i.e. they don't have any common column? is it possible in SQL? My reader got confused because he only knows about INNER join and OUTER join which require a key column like dept_id which is the primary key in one table like Department and foreign key in another table like Employee. He couldn't answer the question, though he did tell them about you can select data from multiple tables by typing multiple table names in from clause using a comma.

Difference between Primary key vs Candidate Key in SQL Database? Example

Primary key vs Candidate Key

What is the difference between primary key and candidate key is another popular SQL and database interview question which appears in various programming interviews now and then? The concept of primary key and candidate key is not just important from the interview point of view but also in designing databases and normalization. By the way, this is my second post about primary keys, In the last one, we have seen a comparison of primary key vs unique key, which also happens to be one of the frequently asked database questions.

Difference between Clustered and Non-Clustered Indexes in Database? SQL Question Answer

Clustered vs Nonclustered Indexes in SQL
The difference between Clustered and Nonclustered index in a relational database is one of the most popular SQL interview questions almost as popular as the primary key vs unique key, the difference between truncate and delete, and correlated vs noncorrelated subqueries. Indexes are a very important concept, it makes your queries run fast and if you compare a SELECT query which uses an indexed column to one who doesn't you will see a big difference in performance.

Difference between Primary key vs Unique key in SQL Database? Answer

primary key vs unique key in SQL
The primary key and unique key are two important concepts in a relational database and are used to uniquely identify a row in a table. Both primary key and unique keys can identify a row uniquely but there is some subtle difference between them which we will see in this article. In fact, primary key vs unique is a popular SQL interview question along with classics like truncate vs delete and How to manage transactions in a database, mostly asked to fresher and 2 to 3 years experience guys in any programming language. SQL is not just limited to any DBA or PLSQL developer but it's an important skill even for Java programmers and you can expect SQL interview questions even in many Java interviews.

Where Is Python Used In The Real World?

Hello guys, if you are wondering where is Python used in real world before you decide whether to learn Python programming language or not then its actually a good question. While everyone is talking about Python's popularity, it make sense to do research and find out which industries in Software development is using Python as their primary language. You will be surprised to know that like Java Python is also almost everywhere. Python is now used in Artificial Intelligence, Web Development, Game Development, Building Desktop and UI Apps, Machine Learning, Data Science, Data Analysis, Building Mobile apps, Web Scrapping, and most importantly on Automation. So, you can see that Python is widely accepted and used and learning Python is the best decision you can take to start your career as Software Developer.

Top 10 tools for SQL Developers and Database Administrators

Hello guys, if you are a SQL database administrator a SQL Developer, a good knowledge of database tools can really help. It even been said that a craftsman is as good as his tools. So, you should spend some time and find out the tools which can help you with your job with respect to Database and SQL. Here are the main 10 free data set instruments that play out a great many explicit capabilities. The thought behind this rundown is to assist you with picking the right devices that best met your requirements.

Top 5 advanced JavaScript function concepts to Learn

Introduction:
A function is a piece or block of code that is created to perform single or multiple tasks. Every major programming language has functions because functions are one of the essential parts of modern programming. JavaScript also supports functions. Over time, JavaScript has upgraded functions in several ways to make them more programmer-friendly. In recent years, more and more advanced concepts are added in JavaScript. In this article, we are going to discuss the advanced working with functions in JavaScript.

Top 7 Gift Ideas for Programmers, Coders, and Software Developers in 2025 [UPDATED]

If you are planning for a surprise gift to your programmer boyfriend and husband this holiday season like Black Friday, Christmas, or New Year, or maybe on his next birthday, but not sure what to gift, then you have come to the right place. In this article, I am going to share some of the best gifts ideas for programmers and developers, gifts that every programmer wishes for. To be honest with you, buying a gift is easy, but finding the right gift is very tough. I have spent countless hours on the internet to find a perfect gift for one of my colleague's husbands, and this article is a result of that research.

Top 20 UI and UX Design Interview Questions and Answers

Hello folks, if you are a fresher who want to start your career in UI and UX design or a UI or UX Designer and preparing for your next job and looking for popular UI/UX interview questions for preparation then you have come to the right place. Earlier, I have shared HTML Interview Question, CSS Interview Questions, web development questions, and JavaScript Interview Questions and in this article, I am going to share common UI and UX interview questions with answers. If you have worked in UI and UX design for quite sometime then you may know the answers of these questions but if you are new then you may need to go through these best UI and UX design courses to refresh you knowledge about essential UI and UX design concepts.

Top 5 Udemy Courses to Learn Distributed Systems in 2025

Hello guys, Distributed systems are the backbone of modern applications, enabling scalability, fault tolerance, and high availability. Whether you’re building microservices, cloud applications, or real-time systems, understanding distributed systems is crucial. If you want to learn Distributed System in 2025 and looking for resources then you have come to the right place. Earlier, I have shared best System Design Books, System Design Questions and best Places to learn System Design and in this article, I am going to share best Distributed System courses from Udemy, one of my favorite place to learn programming and technical stuff.

Is System Design Interview Inside Guide Vol 1 and 2 Book Worth Reading in 2025? Review

Hello guys, if you are preparing for System design interviews or Software Design Interviews, then you must have come across System Design Interview - An Insider's Guide by Alex Xu, one of the most popular book on System Design after Designing Data-Intensive Applications by Martin Kleppmann. I first come across Alex Xu on Twitter when one of his image about how HTTPS works went viral. The image was quite detailed and presentable so I start following Alex and then I come across ByteByteGo, his online System design course and his book System Design Interview - An Insider's Guide.

10 Best System Design Interview Courses for Software Engineers in 2025

Hello guys, if you are preparing for System design interview and looking for best online courses to learn essential System design concepts like load balancing, API Gateway, scalability, Microservices architecture as well as learn how to solve popular System design questions like how to design YouTube, WhatsApp, Parking Lot, Library System as well when to use NoSQL and SQL then you have come to the right place.

Top 15 Courses to Learn System Design and Software Architecture in 2025 - Best of Lot

Software design or System design is one of the tricky concepts to master. You can quickly learn a programming language like Java or Python, but creating software using that programming language is a totally different thing. That's where software design and coding skills come to the rescue. It's actually an art to structure your program, design your modules, specify boundaries and interactions with other parts of the system so that they are easier to read, maintain, and flexible to change. It's one of the most essential skills for a software developer but often gets ignored. If you look for an online course to learn Software design and architecture, you won't find many, forget about good ones.

Review - Is AlgoMonster Good Resource For Coding Interview Preparation in 2025?

Hello guys, if you are preparing for coding interviews and wondering whether joining AlgoMonster is right decision or not then you have come to the right place. Earlier I have shared best website for coding interview preparation, books, and best coding interview courses and in this article, we will review Algo Monster, one of the top site for coding interview preparation. Before we review Algomonster, let me tell you what it really is. For those of you who don't know, Algomonster is a legit site and basically an interview prep site with a focus on coding that will help you clear your interview and land your dream coding job.

Top 8 Online Courses to Learn System Design and Software Architecture on Udemy (2025)

Hello friends, If you're aiming to master Software Architecture and System Design in 2025, you're in the right place. Whether you're preparing for tough technical interviews or simply want to become a better software engineer, understanding system design is a must. But let’s be honest—it’s also one of the most challenging topics to master. Many developers, including experienced ones, struggle with system design interviews—especially when applying to top tech companies like Google, Meta, Amazon, Apple, Microsoft, and Netflix (formerly known as FAANG, now MAANG).

70+ Coding Interview Questions for Software Engineers and Developers in 2025

There are a lot of computer science graduates and programmers applying for programming, coding, and software development roles at startups like Uber and Netflix and big organizations like Amazon, Microsoft, and Google. They are also quite popular on service-based companies like Infosys, TCS, or Luxsoft, but many of them have no idea of what kind of programming interview questions to expect when you’re applying for a job with these companies. Things have also changed a lot in the last few years and coding interviews have become tougher. Now you need to go through a couple of coding interview rounds but you also need to prepare for System design problems which wasn’t normal in the last decade.

Difference between Daemon Thread vs User Thread in Java? Example

A thread is used to perform parallel execution in Java e.g. while rendering screen your program is also downloading the data from the internet in the background. There are two types of threads in Java, user thread and daemon thread, both of which can use to implement parallel processing in Java depending upon the priority and importance of the task. The main difference between a user thread and a daemon thread is that your Java program will not finish execution until one of the user threads is live. JVM will wait for all active user threads to finish their execution before it shutdown itself.

How to join two threads in Java? Thread.join() example

You can join two threads in Java by using the join() method from java.lang.Thread class. Why do you join threads? because you want one thread to wait for another before starts processing. It's like a relay race where the second runner waits until the first runner comes and hands over the flag to him. Remember, unlike sleep(), join() is not a static method so you need an object of java.lang.Thread class to call this method. Now, who calls and who wants, and which thread dies? for example, if you have two threads in your program main thread and the T1 which you have created.

How to stop a thread in Java? Example

Today we're going to learn about how to stop a thread in Java. It's easy to start a thread in Java because you have a start() method but it's difficult to stop the thread because there is no working stop() method. Well, there was a stop() method in Thread class, when Java was first released but that was deprecated later. In today's Java version, You can stop a thread by using a boolean volatile variable. If you remember, threads in Java start execution from the run() method and stop, when it comes out of the run() method, either normally or due to any exception. You can leverage this property to stop the thread.

10 Things about Threads Every Java Programmer Should Know

Thread in Java is one of those topics which always confuse beginners but given the importance and strength it provides to the Java language, it's very important for every Java developer to learn and understand the fundamental concept of multi-threading and basic points about Thread in Java. I had started thread programming in Java by animating a couple of words in Applets, that was an amazing experience to code animation, but after spending almost 10 years on developing core Java applications and I am still discovering things about threading and concurrency. My first program which involves Thread had three words dropping from each corner of the screen and I was excited to see that animation driven by Java thread.

Difference between int and Integer Types in Java? Example

Both int and Integer are two important data types in Java that often cause confusion between new Java developers. Both int and Integer are used to represent numeric data and related to each other in the sense of primitive and Object. Int is a primitive data type that has 32-bit and stores values from -2^31 to 2^31-1 while Integer is a class that wraps an int primitive inside it. In this article, you will learn why we need Integer Class in Java, particularly, if we already had the int data type, how to convert from int to Integer in Java, and various points on Integer in Java, ranging from basics to advanced BigInteger and AtomicInteger stuff.

What is Thread and Runnable in Java? Example

What is Thread in Java?

Thread in Java is an independent path of execution that is used to run two tasks in parallel. When two threads run in parallel that is called multithreading in Java. Java is multithreaded from the start and has excellent support of Thread at language level e.g. java.lang.Thread class, synchronized keyword, volatile and final keyword make writing concurrent programs easier in Java than any other programming language like C++. Being multi-threaded is also a reason for Java's popularity and being the number one programming language.

What is blank final variable in Java - Example

What is a blank final variable in Java?

The blank final variable in Java is a final variable that is not initialized while declaration, instead they are initialized in a constructor. Java compiler will complain if a blank final variable is not initialized during construction. If you have more than one constructor or overloaded constructor in your class then a blank final variable must be initialized in all of them, failing to do so is a compile-time error in Java. Alternatively, you can use constructor chaining to call one constructor from another using this keyword, in order to delegate initialization of a blank final variable in Java. In this Java tutorial, we will see what is blank final variable is in Java and a code example on How to use a blank final variable.

Access Modifiers in Java - Public, Private, Protected, and Package Examples

public, private, protected and package or default are four access modifiers available in Java. These access modifiers provide Java programmers to control the accessibility or visibility of a class, method, or any field of a class. A good understanding of public, private, or protected modifiers is required in order to implement proper encapsulation in Java and create a Java program that is easier to maintain. In this Java tutorial, we will see what is public, private, protected and default modifiers are, which modifiers can be used with top-level class and nested class, and what is the difference between public, private, protected, and default modifiers in Java.

How to display date in multiple timezone in Java with Example - PST GMT

We can use SimpleDateFormat class to display a date in multiple Timezone in Java. While working in a global Java application it's quite common to display dates in the different time zone, classical example is Server is running on either PST or GMT timezone and clients are global or at least running on global trading hubs like Hong-kong, Mumbai, Tokyo, London, etc. Unfortunately, the Date and Time API in Java is quite tricky and until you have a good understanding of Date and Time classes and methods like Calendar, SimpleDateFormat, and thread-safety issues, You can easily create bugs.

JDBC - How to Convert java.sql.Date to java.util.Date in Java with Example

How to convert java.sql.Date into a java.util.Date and vice-versa is a popular JDBC interview question which is also asked a follow-up question of the difference between java.sql.Date and java.util.The date which we have seen in our last article. Since both SQL date and Util date store values as a long millisecond, converting them back and forth is easy. Both java.sql.Date and java.util.The date provides a convenient method called getTime() which returns a long millisecond equivalent of a wrapped date value. Here is a quick example of converting java.util.Date to java.sql.Date and then back to util Date.

5 Essential JDK 7 Features for Java Programmers

What is new in Java or JDK 7
It's close to a year now JDK 7 or Java 7 has been released, still, programmer asks what is new in Java 7 ? What is the best feature introduced in JDK7, where is the list of all Java 7 new features, etc? I thought to let's document Top 5 new features introduced in Java 7 for easy reference, this will not only answer What is new in Java 7 but also provide a quick overview of What are those features in Java 7. Java 7 introduced many new features in Java programming language like try-catch with a resource, String in Switch, etc but it also makes a lot of changes on Java Development API by introducing a new File API in Java and several other minor changes. Like you can now find hidden files from the Java programs without applying any hack. anyway let's see my list of Top 5 Java 7 features :

Difference between DOM vs SAX Parser in Java - XML Parsing in Java

DOM vs SAX parser in Java
DOM and SAX parser are the two most popular parsers used in the Java programming language to parse XML documents. DOM and SAX concept is originally XML concept and Java programming language just provide an API to implement these parsers. Despite both DOM and SAX are used in XML parsing, they are completely different from each other. In fact difference between DOM and SAX parser is a popular Java interview question asked during Java and XML interviews. DOM and SAX parser has a different way of working, which makes Java programmer understand the difference between DOM and SAX parser even more important.

How to configure Daily Log File Rolling in Java using Log4j - DailyRollingFileAppender Example

Hello guys, today, I am going to share one small but the useful tip about logging in to your Java application. If your Java application is a weekly restart, I mean it starts on Sunday and not again on the weekday, then you really want to have separate log files for each day. This helps during troubleshooting and debugging. But If you are facing a problem where your log files are not rolling daily and becoming bigger and bigger after each passing day, making it challenging to search anything in case of any production issue, then it might be that you have not configured your Log4j properly to roll your logs daily.

Eclipse and NetBeans Keyboard Shortcuts for Java Programmers - Example

If you are a Java developer who has been using Eclipse for Java development, but you need to use Netbeans for your current project for various reasons, this article is for you. Whenever we transition between tools, we need the equivalent of one into other. For example, if you are an Eclipse power user who is used to Ctrl + Shift + R and Ctrl + Shift + T, you miss those as soon as you start using Netbeans shortcuts. One thing to keep your productivity up is to quickly find the equivalent shortcut in a new tool, like, Netbeans if you are switching from Eclipse or vice-versa.

How to convert int value to a Long object in Java? Examples

Suppose you have an int variable but the part of the application is expecting a Long object, how do you convert a primitive int to a Long object in Java? It shouldn't be a problem, right? after all long is a bigger data type than int, so all int values are acceptable as long, but we also need a Long object, not just the long primitive value. Now, the problem is reduced to converting a long primitive to a Long object, which is not really a problem if you are running on a JRE version higher than Java 5. But, sometimes autoboxing is not efficient like when you have to convert multiple long values into the Long object in a loop.

How to Create Random Alphabetic or AlphaNumeric String of given length in Java? SecureRandom Example

Hello Java programmers, if you want to create a random alphanumeric string and looking for examples then you have come to the right place. Earlier, I have shown you how to generate random numbers in a range, and in this article, you'll learn how to generate random alphanumeric String in Java. Suppose, you want to generate an alphabetic or alphanumeric string of a given length in Java? How do you do it? Well, if you are like me, you probably search a library like Apache commons-lang or Google Guava for something which can do this task. It's a good thing. There is no point in re-inventing a wheel if a tried and tested solution already exists. In fact, Effective Java, the most respected book in the Java world also suggests knowing and use your library.

How to Order and Sort Objects in Java? Comparator and Comparable Example

Java Object Sorting Example

How do you sort a list of Objects in Java is one of the frequently asked coding questions in Java interviews and surprisingly not every Java programmers know How sorting of object happens in Java. Comparator and Comparable interface along with Collections.sort() method are used to sort the list of objects in Java. compare() and compareTo() method of Comparator and Comparable interface provides comparison logic needed for sorting objects. compareTo() method is used to provide Object's natural order sorting and compare() method is used to sort Object with any arbitrary field.

Difference between int and Integer data type in Java? Example

The first and foremost difference between an int and Integer or a char and Character is that the former is a primitive data type while the latter is a class, also known as wrapper class because they wrap the primitive data type inside it. When you first start learning Java, you start with primitive data types like int, long, char, byte, boolean, float, and double but slowly you learn about Object, and sometime later you know about Integer, Long, Character, Byte, Boolean, Float, and Double. At this point in time, you may wonder, what is the real difference between an int and Integer? isn't both the same? We can pass Integer where int is expected and vice-versa then why on the earth we have both int and Integer?

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