jQuery Tutorial - How to modify multiple HTML elements in one line

jQuery allows you to modify multiples elements in one go, you can modify attributes, text, or color of multiple HTML elements by executing just one line of jQuery code. In this jQuery tutorial, I will show you how to modify multiple <li> elements in one go. In our example, we have a couple of <li> tag to display sub-headings, now we will change them in one go using jQuery. If you look at our HTML, we have an ordered list <ol> to display top 10 programming languages, each of them is a <li> item. We also have one button, "Click Me", which will when clicked, changes all <li> item's text to "jQuery is the new Boss". Here is the jQuery code, which does that.

Can you take Spring certification without Pivotal Training Course?

Yes, you can take Spring certification without taking mandatory Spring training. Pivotal, the company behind Spring, has announced on 10th May 2017 that "Spring Certification Exams are now available for individual purchase, without enrolling in the course". This is one of the most exciting changes in the Spring certification program since it's launched 10 years back. The cost of Spring certification was the single, biggest obstacle for many experienced Java and Spring developers to get certified for their Spring framework skills. This step from Pivotal is a really positive step and gives a real chance to many experienced developers in cost sensitive countries like India to get certified for their skill. Now, you don't have to enroll for a 50K training if you have good knowledge of Spring certification and exam objectives, just like Java certification, you can buy the Spring certification voucher @ 200 USD and take the exam online or offline at any test center.

Solution of java.lang.OutOfMemoryError: GC overhead limit exceeded

The java.lang.OutOfMemoryError: GC overhead limit exceeded is another type of OutOfMemoryError in Java which comes when JVM spent too much time doing garbage collection without any success.  For example, if almost 98% of CPU for a Java process is busy doing GC and reclaims very less amount of Java heap space around 2%, then JVM throws "java.lang.OutOfMemoryError: GC overhead limit exceeded" error. Though, the definition of 98% CPU time may vary between different Garbage collector and different JVM version.  Unlike java.lang.OutOfMemoryError: Java heap space and java.langOutOfMemory: Permgen space, this is not so frequent and you will rarely encounter this error in your Java application, but this also denotes resource exhaustion.

How to enable Spring Security in Java Web application?

Spring Security is one of the most popular frameworks to implement security in Java web application in a declarative way. It provides several essential security features e.g. LDAP authentication, authorization, role-based access control,  remembers the password, URL protection, concurrent active sessions management etc. In order to enable Spring security in Java Web application, you need to do configure three things, declare a delegating proxy filter in web.xml, add the ContextLoaderListener in web.xml and provide actual security constraints on applicationContext-Security.xml file. Since Spring security uses a chain of filters to implement various security constraints, also known as Spring's "security chain filter", it relies on web container for the initialization of delegating filter proxy.

How to print 1 to 100 without using loop in Java

This is one of the interesting problems  I have seen on coding interviews  for beginners. The program has surprise element by saying that you need to print 1 to 100 without using a loop e.g. for, forEach or enhanced for loop. This brings out some innovative solutions from candidates which tell a lot about their approach, knowledge, and attitude. I remember, asking this question during campus recruitment to at least 5 candidates. The first one took 5 minutes to think and then come up with the brute force way where he just copies pasted 100 System.out.println() and printed number 1 to 100 but when we asked to improve that, he couldn't too that. Unfortunately, he didn't think that recursion can replace an iterative algorithm without using a loop.

Difference between Servlet and JSP?

Servlet and JSP are two of the most popular Java web technologies to generate dynamic content in Java web applications there is some key difference between them. For example, Servlet is designed for Java developers as most of the coding is done in Java, while JSP was designed and developed for web GUI developer e.g. guys who write HTML and JavaScript and that's why you see the coding in JSP is tag based. Even though you can use HTML tags as String inside Servlet and Java code as Scriptlet inside JSP, both are considered as bad practice and should be avoided at all cost because they are very hard to maintain. The different nature of Servlet and JSP also allows frontend and backend developers to work in parallel, JSP work is mostly done by frontend developers while Servlet work is done by backend developers.