A Guide to etcd

Explore etcd, an open-source distributed key-value store. Understand its fundamental concepts, features, and use cases with examples.

Spark DataFrame

Spark’s DataFrame component is an essential part of its API. It represents data in a table like way so we can perform operations on it. We look at the Java Dataset type, which is used to interact with DataFrames and we see how to read data from a JSON file and write it to a database.

Getting Started With Apache Derby

A quick guide to the Apache Derby open-source relational database engine, this article discusses all the major aspects from installing and configuring it to working with its various tools. It also shows how we can connect to it programmatically using plain JDBC and in a Spring Boot application.

Digital Signatures in Java

Java provides support for digital signature via the JCA APIs. See how to digitally sign and verify messages with public/private key cryptography.