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5 ways to redirect a web page using JavaScript and jQuery

When an HTTP request for one page automatically goes to another page then it is called a redirection. The redirection of a web page is used for different reasons e.g. redirecting to a different domain e.g. when you move your website from one URL to another URL or redirecting to a more recent version of a page you are looking at it. There are many ways to redirect a web page and different web technologies provide different ways e.g. Java provides sendRedirect() and forward() method for redirection. The redirection can also be divided into two categories, client side and server side. In client side, redirection client is responsible for routing request to another URL but in server side redirection, its server's job to redirect to a new page.

String Rotation in Java - Write a Program to check if strings are rotations of each other or not

String based algorithmic questions are very popular in Java interviews e.g. checking if two String is the anagram of each other (see), or checking if given String is a palindrome (see), or just finding permutations of given String (see). One of such popular String based interview questions is about to check if two Strings are a rotation of each other in Java. In order to solve this question, you should know what is String rotation? Well, A string is made of characters and you just rotate the String around any character e.g. "programming" will become "ingprogramm" if we rotate the String on trailing character 3 times. A k-rotation on a string takes the trailing k characters of the string and attaches it to the beginning of the string in the same order. You can rotate the String either in the clock wise (right from the top) or anti-clockwise(left from the top). The string can also be rotated in one go e.g. "123456" will become "456123" if we rotate 456 to the left around character "3".

Solving org.springframework.beans.factory.BeanCreationException: Error creating bean with name X [Java Spring]

If you are using Spring framework in your Java application and getting this error during startup it means Spring is not able to initialize the bean X and add into its application context, Why? There could be multiple reasons e.g. a typo on spring bean name. Let's take a closer look at the stack trace to find out the real reason:

BeanInstantiationException: Could not instantiate bean class [X]: No default constructor found; nested exception is java.lang.NoSuchMethodException: X.()

Here X is the class, which is declared as Spring bean. The error clearly says that default constructor is not present in class X. By default, Spring will try to instantiate beans by calling the default or no-argument constructor and if it doesn't find the default, no-argument constructor then it is not able to initialize the bean and hence it throws the BeanInstantiationException during startup, the real reason is also appended into stack trace as NoSuchMethodException.

How to sort an ArrayList of Objects using Comparator in Java 8 - Ascending and Descending Order

There are a lot of examples of Sorting ArrayList in Java on the internet, but most of them use either String or Integer objects to explain sorting, which is not enough, because in real world you may have to sort a list of custom objects e.g. your domain or business objects like Employee, Book, Order, Trade etc. In order to sort an ArrayList of objects, you need two things, first a class to provider ordering and a method to provide sorting. If you know about ordering and sorting in Java then you know that Comparable and Comparator class is used to provide the ordering for objects. The Comparable interface provides natural order e.g. lexicographic order of String or name for Employees, while Comparator is used to provide custom order. It gives you the flexibility to sort your objects on the parameter you want e.g. you can sort a list of Coupon objects on the percentage discount, expiry dates, or based upon the total cost.