By Simon Roberts and Mikalai Zaikin
Explore the allowed method return types to see where the code succeeds… or fails.
By Simon Roberts and Mikalai Zaikin
Test your knowledge of Java’s primitive operators.
By Simon Roberts and Mikalai Zaikin
Here’s what happens when good code meets bad people.
By Simon Roberts and Mikalai Zaikin
You now need only pass a single exam to become a certified Java SE 11 Developer.
By Simon Roberts and Mikalai Zaikin
Test your knowledge of static fields in Java.
By Simon Roberts and Mikalai Zaikin
Test your knowledge of abstract classes and their methods.
By Simon Roberts and Mikalai Zaikin
Test your knowledge of the java.io.Serializable interface.
By Simon Roberts and Mikalai Zaikin
Test your knowledge of a key object-oriented programming concept.
By Simon Roberts and Mikalai Zaikin
Test your knowledge of the java.nio.file.Files class.
By Simon Roberts and Mikalai Zaikin
Test your knowledge of what happens when you use the ExecutorService.
By Simon Roberts and Mikalai Zaikin
Test your knowledge of Java classes, such as their valid names, the use of variables inside a method, and the number of import statements.
By Simon Roberts and Mikalai Zaikin
Work with lists while avoiding unpleasant UnsupportedOperationException errors.
By Simon Roberts and Mikalai Zaikin
Streams are complicated. With the right approach, they can be very efficient too.
By Simon Roberts and Mikalai Zaikin
Know which command-line utilities are mandatory for distributing applications with a custom JRE.
By Simon Roberts and Mikalai Zaikin
Do you know how to use Optional? Find out in the latest by Simon and Mikalai.
By Simon Roberts and Mikalai Zaikin
PreparedStatement sends SQL to a database. Let’s see how it works.
By Simon Roberts and Mikalai Zaikin
This intermediate-level Java SE 11 certification quiz tests your ability to declare modules and enable access between modules.
By Simon Roberts and Mikalai Zaikin
This Java certification quiz investigates the meaning of default accessibility and how it influences classes in different packages.
By Simon Roberts and Mikalai Zaikin
Understanding the checked exception mechanism requires that you understand how to declare a method that throws a checked exception, and how that differs from a method that either does not throw any exceptions or throws only unchecked ones.
By Simon Roberts and Mikalai Zaikin
See if you know how to improve code by refactoring.