Чашечка Java

Top Java Blogs Weekly: Best of 35/2022 Best of Top Java Blogs, year 2022, week 35 Read: https://www.topjavablogs.com/news/best-of-35-2022

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Java + Spring Boot + Microservices Example - How to create a Microservice in Java using Spring Boot? Hello guys, if you are wondering how to create a Microservice in Java and Spring Boot then you are ar the right place. In the past, I have shared best Spring Boot courses for Microservices, Interview Questionsas well as essential Microservice design principles and patternslike circuit breaker, CQRS, Event sourcing etc and In this article, we will cover the fundamentals of microservices with Spring Boot utilizing Spring cloud. We will cover a few fundamental ideas and then we will make a little micro-service to give you an outline. I will also share step by step guide to make Microservices in Java and then deploy them using Docker and Kubernetes on Cloud. Java Interview questions and tutorials Read: http://www.java67.com/2022/08/java-spring-boot-microservices-example.html

How to check if a Number is Power of Two in Java? [Bitwise AND Example] Hello guys, if you are thinking about how to check if a given number is a power of two without using an arithmetic operator like division then you have come to the right place. In Java, you can use bitwise operators like bitwise AND check if a given number if the power of two or if the given number is even or odd. In this Java Programming tutorial, you will learn how to check if the number is the Power of two using a bitwise operator. The main purpose of this program is to teach you how to use bit-wise operators like bitwise AND (&)  in Java. A number is said to be the power of two if all its prime factors are 2, but in the binary world, things work a little differently. Java Interview questions and tutorials Read: http://www.java67.com/2015/06/how-to-use-bitwise-operator-in-java.html

Top 20 Java Access Modifier Interview Questions Answers for 1 to 2 Years Experienced Access modifiers is one of the essential concept in Java and every programmer should be familiar with, and because of its importance, its also a popular topic in Java interviews. Access modifier can be applied to class, method, fields, and variables and as the name suggests they control the access. Like who can access that particular class, method or variable. For example, public modifier provides universal access which means any public class, method or variable is accessible by everyone and everywhere. In other words, you can access a public class both within the package and outside the package. Java Interview questions and tutorials Read: http://www.java67.com/2022/05/java-access-modifier-interview.html

How to convert an ArrayList to Array in Java? ArrayList of String Example Hello guys, if you are wondering how to convert an ArrayList of objects to an array of Object in Java then you have come at the right place. In this article, I will show you a couple of ways to convert an ArrayList to Array in Java. For example, you can start with creating a new array and then copying elements from ArrayList to array, or you can also use use Stream to go through all elements of ArrayList and then collect result in an array. In this example, we will use Arrays.copyOf()method to convert a given ArrayList to array in Java. This method can be used to convert any ArrayList like ArrayList of Integer, String or any custom object to Array in Java. Java Interview questions and tutorials Read: http://www.java67.com/2012/09/java-program-to-convert-string-arraylist-to-string-array.html

How to Delete Objects from ArrayList in Java? ArrayList.remove() method Example Hello guys, if you are wondering how to remove an element from a given ArrayList in Java then you are at right place. Earlier, I have shared how to sort ArrayList in Java as well how to loop over ArrayList in Java and In this Java ArrayList tutorial, you will learn how to remove elements from ArrayList in Java e.g. you can remove String from ArrayList of String or Integer from ArrayList of Integers. There are actually two methods to remove an existing element from ArrayList, first by using the remove(int index) method, which removes elements with a given index, remember the index starts with zero in ArrayList. Java Interview questions and tutorials Read: http://www.java67.com/2015/06/how-to-remove-elements-from-arraylist.html

5 Difference between Hashtable vs HashMap in Java? Answer Hashtable vs HashMap in Java Hashtable and HashMap are two hash-based collections in Java and are used to store objects as key-value pairs. Despite being hash-based and similar in functionality there is a significant difference between Hashtable and HashMap and without understanding those differences if you use Hashtable in place of HashMap then you may run into series of subtle programs which is hard to find and debug. Unlike the Difference between ArrayList and HashMap, Differences between Hashtable and HashMap are more subtle because both are similar kinds of collections. Before seeing the difference between HashMap and Hashtable let's see some common things between HashMap and Hashtable in Java. Java Interview questions and tutorials Read: http://www.java67.com/2012/08/5-difference-between-hashtable-hashmap-Java-collection.html

How to write a Parameterized Method in Java using Generics? Example Hello guys, if you are wondering how to write a parameterized method in Java using Generics then you are at right place. Earlier, I  have shared Complete Java Generics tutorial as well as popular Generics Interview Questions and in this article, I will teach you how to write a parameterized method using Generics in Java step by step. A method is called a generic method if you can pass any type of parameter to it and it will function the same like it allows the same logic to be applied to different types. It's known as a type-safe method as well. Java Interview questions and tutorials Read: http://www.java67.com/2019/09/how-to-write-generic-method-in-java.html

10 Examples of nslookup command in Linux and Windows Hello guys, if you are wondering what is nslookup command and how to use in Linux and Windows then you are at right place. In the past, I have shared examples of crontab, find, grep, netstat, and curl commandand In this article, I will share 10 different examples of nslookup command, each using its different powerful command line option to give you the tool you need to deal with networking  related queries. I often use nslookup command to convert a given IP address to hostname or a given hostname to IP address. For example, when I see an IP address in our log file and want to find which host that request is coming from, I use nslookup. Java Interview questions and tutorials Read: http://www.java67.com/2022/08/10-examples-of-nslookup-command-in.html

Difference between Polymorphism vs Inheritance in Java and Object Oriented Programming - Example Programmers often confused among different object-oriented concepts e.g. between Composition and Inheritance, between abstraction and encapsulation, and sometimes between Polymorphism and Inheritance. In this article, we will explore the third one, Polymorphism vs Inheritance. Like in the real world, Inheritance is used to define the relationship between two classes. It's similar to the Father-Son relationship. In object-oriented programming, we have a Parent class (also known as the superclass) and a Child class (also known as the subclass). Similar to the real world, a Child inherits Parents' qualities, like its attributes, methods, and code. Java Interview questions and tutorials Read: http://www.java67.com/2014/04/difference-between-polymorphism-and-Inheritance-java-oops.html

How to convert ArrayList to Comma Separated or Delimited String in Java - Spring Example Some time we need to convert ArrayList to Stringin Java programming language in order to pass that String to stored procedure, any method or any other program. Unfortunately Java collection framework doesn't provide any direct utility method to convert ArrayListto Stringin Java. But Spring framework which is famous for dependency Injection and its IOC container also provides API with common utilities like method to convert Collection to String in Java. You can convert ArrayList to String using Spring Framework's StringUtils class. StringUtils class provide three methods to convert any collection e.g. ArrayList to String in Java, as shown below: Java Interview questions and tutorials Read: http://www.java67.com/2012/10/how-to-convert-arraylist-to-string-in-java-example.html

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10 Examples of head and tail command in Linux Hello guys, if you are wondering how to use head and tail command in Linux then you have come to the right place. Both head and command are great tool to view content from files in Linux. As the name suggest, "head" is used to view the top portion of the file and "tail" is used to see the file content from bottom. For example when you say "head data.json" then it will display first 10 lines of the file and when you say "tail data.json" then it will display last 10 lines of the file. As a Java developer, I find myself using tail more often than head while checking logs. As you can use tail to see the last few lines of the log file and you can also use tail -f application.log to see the logs rolling in real time. I often use this command to track request and see what application is doing at a particular time. Java Interview questions and tutorials Read: http://www.java67.com/2022/08/10-examples-of-head-and-tail-command-in.html

Difference between JDK and JRE in Java Platform Java Platform offers JRE and JDK to run Java programs. JRE stands for Java runtime environment and JDK stands for Java development kit. JRE is meant for normal users, who wants to run Java program in their computer. JRE is normally used to run Java programs downloaded over internet e.g. Java Applets and Java Desktop application built using AWT and Swing. The main difference between JRE and JDK, comes from the fact that they are different tools. JDK is created for Java programmers and contains tools required for Java programming, like javac for compiling Java source files to .class files. Without JDK, you can not create Java applications and programs. Java Interview questions and tutorials Read: http://www.java67.com/2013/02/difference-between-jdk-and-jre-in-java.html

Difference between this and super keywords in Java this and super are two special keywords in Java, which is used to represent current instance of a class and it's super class. Java Programmers often confused between them and not very familiar with there special properties, which is asked at various core Java interviews. A couple of questions, which I remember about this and super keyword is that, Can we reassign thisin Java?and the difference between this and super keyword in Java. Do you want to try that? Ok, I am not giving the answer now, rather I will let you know the answer at the end of this post. Java Interview questions and tutorials Read: http://www.java67.com/2013/06/difference-between-this-and-super-keyword-java.html

A Concise Guide to Using Multiple Azure Storage Accounts from a Single Spring Boot Application Read: https://devblogs.microsoft.com/java/a-concise-guide-to-using-multiple-azure-storage-accounts-from-a-single-spring-boot-application/

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8 основных языков для бэкенда На чём обычно пишут бэкенд крупные компании? Рассказываем о 8-ми языках для бэкенда, об их плюсах и о компаниях, где их используют. Читать: «8 основных языков для бэкенда»