[Tutorial] Plotly graph drawing in Java webapp - Part 2

Plotly JavaScript library supports generating various charts. Java Servlet & JSP based web applications can use it to display graphical...

Draw graphs in Java webapp with Plotly - Tutorial

Plotly JavaScript library supports generating various charts. Java Servlet & JSP based web applications can use it to display graphical ...

[Eclipse] How to use local DTDs to validate XMLs

By default Eclipse does not support local DTD files. Because of this, many developers loose a privilege of Eclipse; content assistance for p...

[Eclipse] Exporting & Importing Launch configurations

Many Eclipse "Launch Configuration" created has so much details; OSGi configurations for instance. So there arises a requirement...

[Eclipse] org.osgi.framework.BundleException: Could not find bundle: org.eclipse.equinox.console

With latest Eclipse Kepler 4.3.1 SR1, I tried to run one of my older OSGi projects. Earlier this project was running smoothly with Eclipse ...

OSGi Console of Eclipse Kepler 4.3.1

Eclipse IDE is developed based on OSGi plugin architecture, but I had not seen the list of OSGi bundles that are used in my Eclipse installa...

[Java] Validate opening & closing character pattern in text

How to validate the format of a given string according to a given set of opening-closing character pairs? This has been raised as an intervi...

[Jenkins] Automatically retry a failed build

Are your Jenkins builds failing due to unavoidable reasons like unavailability of external databases, file systems etc? The only solution yo...

Log4j: Quickly integrate with Java project

This is a quick guide on how to use log4j in your Java project. This task requires only five simple steps listed below. Each of these step i...

Minimum difference in two sorted arrays

Given two sorted arrays of same length, find pairs of numbers (one from each array) which has the minimum distance between those two numbers...

Java: Binary Search (recursive) & TestCases

Test cases for Binary search might not be something you have already written, but the implementation must be an old exercise you may have do...

[Part 2] Finding Second Highest Frequent Characters using Java

Initial part of finding second highest frequency characters in a text was discussed previously and covered the scenarios where a single char...

Finding Second Highest Frequent Character in a text with Java

Finding second highest frequency character in a text is last weeks Thursdays Dzone Code Puzzle. Intention of this post is to try and work ou...

Http basic authentication header: Learn with Java code sample

HTTP basic authentication with headers is one of the username & password based methods of securing access to web sites, web applications...

[Tomcat] Rename JSESSIONID cookie name & parameter identifier

Changing default JSESSIONID name of cookie and/or parameter is the objective. Deployed J2EE web applications use browser cookie or parameter...

[Java] The enum constant reference cannot be qualified in a case label of switch statement

"The enum constant reference cannot be qualified in a case label" is an error message you may encounter while using Java enum val...

Data Encryption Decryption using AES Algorithm, Key and Salt with Java Cryptography Extension

In this tutorial we will implement a full data encryption decryption cycle with Java (only data, not file encryption); encrypt some data us...

[Ant] Build .WAR files in Eclipse for Web Applications

Eclipse JEE versions support Java Web Application projects, but other Eclipse versions do not. Java developers need to build WAR (web archiv...

[Tomcat] validateJarFile(servlet-api.jar) - jar not loaded. Offending class: javax/servlet/Servlet.class

org.apache.catalina.loader.WebappClassLoader validateJarFile INFO: validateJarFile(<APP_PATH>\WEB-INF\lib\servlet-api.jar) - jar not ...

Manage HTTP headers with Java Servlets: Quick Notes

In Java Servlets API, both HttpServletRequest and HttpServletResponse interfaces (in javax.servlet.http package) provide methods to prog...