Spring Boot Microservices – Exposing repositories as REST resources
For any application, it is an important functionality to be able to provide its data to the consumer. REST APIs are one of the most popular ways to do so.…
Maven error – invalid target release: 17
We upgraded the project from Java 11 to Java 17, and mvn test hits the Fatal error compiling: error: invalid target release: 17 . This article will show how to…
Maven error – invalid target release: 1.11
Maven compiles and hits the following fatal error messages: Fatal error compiling: error: invalid target release: 1.11 . The article will show you how to fix this error
A simple HttpSessionListener example – active sessions counter
Here’s a simple “HttpSessionListener” example to keep track the total number of active sessions in a web application. If you want to keep monitor your session’s create and remove behavior,…
The Java Archive Tool (JAR) Examples
Learn how to use JAR tool: 1 - Create a jar file, 2 - Update a jar file , 3 - Extract a jar file , 4 - List files…
How to add a manifest into a Jar file
In Java, you can use manifest file to define application’s entry point, adding classpath or package version for a JAR file. In this short tutorial , we will show you…
How to make a Java exe file or executable JAR file
In this tutorial, we will show you how to create a executable JAR – When you double click on it, it runs the defined main class in manifest file.
How to get the Tomcat home directory in Java
Is there a function in Java to retrieve the Tomcat (Catalina) home directory? Yes, Tomcat home directory or Catalina directory is stored at the Java System Property environment. If the…
How to check JDK version that installed on your computer
The Java development kit (JDK) contains tools for Java development, and the Java Runtime Environment (JRE) contains a JVM to convert byte code .class to machine code, and execute it,…
How To Install Apache Tomcat 10 on Ubuntu 20.04
Apache Tomcat is a web server and servlet container that is used to serve Java applications. It’s an open source implementation of the Jakarta Servlet, Jakarta Server Pages, and other…