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Understanding OAuth2 token authentication


1. Introduction In this tutorial, we will be understanding OAuth2 Token Authentication, such that only authenticated users and applications get a valid access token which can be subsequently used to access authorized APIs (which are nothing but the protected resources in OAuth terms) on the server. With token based authentication, the users/applications get access to the protected resources for a certain ...

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Overview of Functional Programming

The developer community seems to be in the midst of a paradigm shift, moving away from object oriented programming (OOP) principles and toward functional programming (FP) principles. We’re at the beginning of this shift. I have seen a number of job postings out there saying they’d like FP experience but would accept someone who wanted to learn. My intention in ...

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Getting to know about java.nio.file.Path – 2

In Part 1 of this, we looked at most of the APIs in the java.nio.file.Path class. In this article, we will look at the remaining APIs. Using register() This API allows us to register an implementation of java.nio.file.WatchService interface which will listen for events like directory creation, modification, and deletion. And it intimates the listeners by means of a java.nio.file.WatchKey. ...

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Alternatives for Agile and Lean Roadmapping: Part 2, Rolling Wave Planning Inside One Quarter

In Part 1, I wrote about thinking in feature sets and how to quickly create a feature set of—with any luck—smaller features. That’s because features don’t arrive at the same rate and they change in value, during a quarter. Because features change in value and because some feature sets need to deliver value on a more regular basis, the real roadmap looks ...

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Lucene’s near-real-time segment index replication

[TL;DR: Apache Lucene 6.0 quietly introduced a powerful new feature called near-real-time (NRT) segment replication, for efficiently and reliably replicating indices from one server to another, and taking advantage of ever faster and cheaper local area networking technologies. Neither of the popular search servers (Elasticsearch, Solr) are using it yet, but it should bring a big increase in indexing and ...

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MQTT Security: Securing Mosquitto Server

This post describes how to implement MQTT security. In more details, we will describe how to securing Mosquitto MQTT server. As you may already know MQTT is one of the most important protocols widely used in Internet of things and in Industrial Internet of things. MQTT is a lightweight messaging oriented protocol where MQTT client exchanges messages through an MQTT server ...

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Streaming large JSON file with Jackson – RxJava FAQ

In the previous article, we learned how to parse excessively large XML files and turn them into RxJava streams. This time let’s look at a large JSON file. We will base our examples on tiny colors.json containing almost 150 records of such format: { "aliceblue": [240, 248, 255, 1], "antiquewhite": [250, 235, 215, 1], "aqua": [0, 255, 255, 1], "aquamarine": [127, 255, 212, 1], ...

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The Apache Ignite Native persistence, a brief overview


In-memory approaches can achieve blazing speed by putting the working set of the data into the system memory. When all data is kept in memory, the need to deal with issues arising from the use of traditional spinning disks disappears. This means, for instance, there is no need to maintain additional cache copies of data and manage synchronization between them. ...

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