How to check the JDK version of a class file
When running a Java application it is mandatory that the JRE version to match or to be higher that the JDK version used to compile the application.
You will get the "Unsupported major.minor version 52.0" error when trying to run an Java 1.8 application using a lower version of Java.
Robots.txt File in SEO
A robots.txt file tells search engine crawlers which pages or files the crawler can or can't request from your site.
This is used mainly to avoid overloading your site with requests; it is not a mechanism for keeping a web page out
of Google. To keep a web page out of Google, you should use noindex directives, or to password-protect
your page.
How to read CSV file in Golang
How to read CSV file in Golang using reader from encoding/csv package. For this example we took an simple example of a CSV file containing three columns name, address and phone.
How to fix apt lock-frontend error in Ubuntu
How to fix the E: Could not get lock /var/lib/dpkg/lock-frontend - open (11: Resource temporarily unavailable) error.
How to get the dimensions of an image in Golang
Here are two simple methods to get the dimensions of an image in Golang: using image.DecodeConfig method if the image is not already loaded and image.Decode method is the image is loaded.
How to change Tomcat default port
How to change Tomcat default port 8080 to any other port. Three steps: locate server.xml file, edit and restart the Tomcat service.
