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developerWorks (IBM)
Copyright 2004 IBM Corporation.
Unit 23: Java in the cloud
Learn the structure, syntax, and programming paradigm of the Java platform and language. Start by mastering the essentials of object-oriented programming on the Java platform, and progress incrementally to the more-sophisticated syntax and libraries that you need to develop complex, real-world Java applications.
Class sharing in Eclipse OpenJ9
Memory footprint and startup time are important performance metrics for a Java virtual machine (JVM). The memory footprint becomes especially important in the cloud environment since you pay for the memory your application uses. This tutorial shows you how to use the shared classes feature in Eclipse OpenJ9 to reduce the memory footprint and improve your JVM startup time.
Get started with Servlet 4.0
Servlet 4.0 fully integrates HTTP/2's server push technology, and also enables runtime discovery of a servlet's mapping URL. With video demonstrations and code examples, this hands-on tutorial gets you started with HTTP/2 server push and the new HttpServletMapping interface in Java servlet and JSF applications.
5 things you didn't know about...: MicroProfile 1.3
Eclipse MicroProfile has just delivered five new APIs for developing Java cloud-native microservices. Get the highlights of what's new in MicroProfile 1.3, with code examples that will have you up and running in no time.
A Cambrian Explosion of DevOps Tools
Mik Kersten10/22/2018 at 14:03:03

Any discussion of how to scale the benefits of DevOps invariably lands on tools. The planning, tracking, automation, and management tools we use define the "ground truth" of where and how work happens. One of the most interesting, and at times challenging, aspects of agile and DevOps transformations is the sheer volume of tools involved. How many are required? Must there be so many? Before we proceed further on our journey of defining value stream architecture, let's look at how this ground truth has evolved to get us where we are today.

The Catalyst for DevOps Tool Diversification

We're at an interesting time in the evolution of DevOps tools; the sheer number of available tools points to a sort of Cambrian explosion of tool specialization and diversity. Is all this diversity necessary? Will a big wave of consolidation drive the extinction of most of these tools? What are the lines of specialization driving the diversity, and do we need to consider them when architecting our software value streams? We need to address these questions and inspect the ground truth captured in today's toolchains in order to inform the discussion of how to abstract away the tools' implementation details to focus on the architecture of our value streams.

Getting Started With Angular 7.0
Ankit Sharma10/22/2018 at 14:02:04


Angular has released its latest version, Angular 7.0. In this article, we will explore the following points:

  • What's new in Angular 7.0.
  • Creating your first Angular 7.0 application using the Angular CLI.
  • How to update existing Angular applications to Angular 7.0.

What's New in Angular 7.0

  • While creating a new Angular application, the Angular CLI will prompt the user to select if they want to add features like Angular routing or the format of stylesheets they want to use in their application.
  • Angular 7.0 applications will use the Bundle Budget feature of the Angular CLI to warn developers if the application bundle size exceeds the predefined limit. The default value for the warning is set to 2MB and for error is 5MB. This value is configurable and can be changed from the angular.json file. This feature enhances the application performance considerably.
  • The Component Dev Kit (CDK) of Angular Material also receives some new features as part of this update. The two newly added feature of CDK is mentioned below:

1. Virtual Scrolling

If you are trying to load a large list of elements then it can affect the application performance. The can be used to load only the visible part of the list on the screen. It will render only the items that can fit on the screen. When the user scrolls through the list then the DOM will load and unload the elements dynamically based on the display size. This feature is not to be confused with infinite scrolling which is altogether a different strategy to load elements. You can read more about Virtual Scrolling here.

8 Ways to Test Your Website Across Old Versions of Internet Explorer
Harshit Paul10/22/2018 at 14:01:04

Testing your website on Internet Explorer is a nightmare for developers as well as testers, especially those who are well versed with modern web technologies. Most frameworks, like Bootstrap or the latest versions of ECMA scripts, do not work when the code is rendered on old versions of Internet Explorer, IE 8 and backward. However, client or business requirements often need a website to run properly in all versions of IE. They face a problem since they don’t have old IE versions installed where they can run the tests. In this article, we shall discuss several procedures for testing your application in old IE versions.

1. Inbuilt Developer Tools

The first thing a developer needs to try is using the inbuilt developer tools on recent versions of IE. The best part is, developer console provides users with the option of going back to old versions of IE where the tests can be carried out. However, it should be kept in mind that this works only in IE 11, IE 10 and IE 9. Since Microsoft has stopped providing support for IE, Microsoft Edge does not have this feature. Also, those tools may not function properly as the rendering engines that are used in original browsers. So, while these tools are useful for developers who are trying to replicate a bug, they are not that helpful when it comes to unit testing an application for finding new bugs.

Elasticsearch Documents and Mappings
Quintessence Anx10/22/2018 at 13:01:03

In Elasticsearch parlance, a document is serialized JSON data. In a typical ELK setup, when you ship a log or metric, it is typically sent along to Logstash which groks, mutates, and otherwise handles the data, as defined by the Logstash configuration. The resulting JSON is indexed in Elasticsearch.

Elasticsearch documents live in a segment of a shard, which is also a Lucene index. As additional documents are shipped, the segments grow. Whenever a search is executed, Elasticsearch checks each segment that is stored in a shard. This means that as the segments grow in quantity, searches becoming increasingly inefficient. To combat this, Elasticsearch will periodically merge similarly sized segments into a single, larger, segment and delete the original, smaller, segments.

Convert an Array of Strings to a List
Language: Java, Expertise: Intermediate - Learn how to use an asList method to convert an argument array into a list.
Using Spliterator to Split the Contents of a List
Language: Java, Expertise: Intermediate - Learn a newer way of splitting and then iterating a list.
Understanding Collections.reverse() in Java
Language: Java, Expertise: Intermediate - See how to reverse a list with a set of values in Java with the reverse() method.
Using Single Quotes in Java
Language: Java, Expertise: Intermediate - Learn more about the intricacies of using single quotes.





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