Learn how to use Collector.groupingBy() to group the equal objects.

Transforming a String into an Optional is simple in Java 8. Is going from an empty String to an empty Optional just as simple?

Learn how to work with multi-dimensional arrays in Java

Learn how the JVM optimizes the amount of memory allocated to String storage in the Java String Pool.

A quick and practical overview of grouping Javax validation constraints.

An overview of clean coding practices in Java.

Take a look at how to get a Date value without the time in Java

Learn how to write and use static and default methods in Java interfaces.

Learn how to convert between a Java float value and a byte array

Discover built-in annotations in Java.

Learn how to copy a directory using core Java features and third-party libraries

Learn various techniques for making shallow and deep copies of Java's HashMap

The JVM's just in time compiler employs multiple techniques to optimize our software as it runs. We explore the various tiers and how they affect startup performance and continued optimization.

Learn to convert a String to a BigInteger in Java.

Learn about immutability and how you can achieve it in a Java object.

Learn different ways of getting the number of digits in an Integer in Java.