Learn how to start using modules in java 9 – a beginner tutorial.
“A man who dares to waste one hour of time has not discovered the value of life.” ― Charles Darwin, The Life & Letters of Charles Darwin
A major enhancement of Java version 9 is the Modules facility. Modules have been designed to be especially useful in building and maintaining large systems.
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Learn the technical aspects of bitcoin address generation.
“You can’t be happy unless you’re unhappy sometimes.” ― Lauren Oliver, Delirium
Let us learn how Bitcoin works by implementing various aspects of the technology, shall we? The technology includes the following aspects.
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Learn how to configure the Tomcat web server with SSL.
“Help someone, you earn a friend. Help someone too much, you make an enemy.” ― Erol Ozan
After covering SSL-enabling the Apache web server and the Nginx web server using an SSL certificate, let us now find out how to secure Apache Tomcat with HTTPS. Tomcat is an open-source java web server intended as a reference implementation of Java Servlet, JavaServer Pages, Java Expression Language and Java WebSocket technologies. For the sake of this article, we shall install version 8.5.28 of the Tomcat web server. This version is the latest in the 8.0 series of the server. Installation of the next version, 9.0, should be similar.
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Convert one value to another in a Streams Operation
“Always and never are two words you should always remember never to use. ” ― Wendell Johnson
Do you know about Java 8 Streams?
Java 8 streams is a very powerful facility for working with collections. What formerly required multiple lines of code and loops can now be accomplished with a single line of code. A part of Java 8 streams is the map() facility which can map one value to another in a stream. In this article, let us examine some common use cases where map() is useful.
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Extend your application’s usability with a scripting interface
“Success is not how high you have climbed, but how you make a positive difference to the world.” ― Roy T. Bennett, The Light in the Heart
A non-trivial program of any type has a reasonably complex interface and probably supports multiple options with several ways of controlling input and output. Invoking such a program can be done via the command line, but here we run into limitations of what you can do with the command line. You can probably add options for all supported settings and multiple modes for the program to run.
Learn how to automate tasks on the web using Selenium
“Indifference and neglect often do much more damage than outright dislike.” ― J.K. Rowling, Harry Potter and the Order of the Phoenix
Selenium is a handy tool for controlling a web browser (such as Google Chrome) through a program. It allows you to automate tasks on a website by using the browser much the same way a human user would. Such automation can be useful for a variety of tasks including: regression testing of web applications, data extraction and more. In this article, we will learn how to use Selenium to drive the Chrome Browser.
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Use XQuery for more powerful XML search than is possible with XPath
“I guess there are never enough books.” ― John Steinbeck, A John Steinbeck Encyclopedia
XPath offers an easy way to search an XML document using java. It is much more convenient than having to crawl through the document tree using the DOM API. XQuery builds on XPath and provides an SQL-like language for querying XML documents. It is also capable of updating and modifying the XML document, something which XPath cannot do. In this article, we present a beginner’s introduction to XQuery and how to use it from java.
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Use XQuery to Query, Update and Modify XML Documents
“Trees that are slow to grow bear the best fruit.” ― Molière
As a Java Programmer, if you work in any way with XML, you should learn about XQuery and how to use it.
XQuery is a query language for XML. It is similar to XPath in that it uses the same or similar constructs to identify specific parts of an XML document.
Continue reading “How to Install and Use Oracle XQuery Processor for Java”
Use XSL Tranformation to Pretty Print and XPath to remove indentation
“Time is a drug. Too much of it kills you.” ― Terry Pratchett, Small Gods
XML is easiest to understand when it is properly indented to indicate the element hierarchy. However the extra space added to XML when it is transported increases file sizes. So it makes sense to remove all extraneous information from the document, including ignorable white space. This article will show you how to indent and pretty print an XML document.
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JAXB converts XML to Java and Jackson handles the Java to JSON Conversion
“You only live once, but if you do it right, once is enough.” ― Mae West
In a previous article we covered the basics of using JAXB with its annotations to convert java objects to XML and back. In this article, we take a look at converting from XML to JSON and back, using jackson for the JSON conversion.
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