In this chapter, we provided an overview of the functionality of the most popular packages of JCL: java.lang, java.util, java.time, java.io, java.nio, java.sql, javax.sql, java.net, java.lang.math, java.math, java.awt, javax.swing, and javafx.
The most popular external libraries were represented by the org.junit, org.mockito, org.apache.log4j, org.slf4j, and org.apache.commons packages. It helps you to avoid writing custom code in the cases when such functionality already exists and can just be imported and used out of the box.
In the next chapter, we will talk about Java threads and demonstrate their usage. We will also explain the difference between parallel and concurrent processing. We will demonstrate how to create a thread and how to execute, monitor, and stop it. It will be very useful material not only for those who are going to write code for multi-threaded processing...
