Note: Java's Object class is poorly named because an "object" is usually an instance of a class. But the class that all classes ultimately and implicitly extend from is called Object. In this course, ...

In Java, the superclass of every class is the Object class. The Object class is at the top of the class hierarchy and serves as the root class for all other classes in Java.

Object-oriented systems are usually partitioned into layers of related responsibilities and only dependencies in one direction are allowed, from higher layers (more specific, less reusable) to lower ...

The agent class above exposes a statically available method for accessing Instrumentation.getObjectSize(Object). The next code listing demonstrates a simple ‘application’ that makes use of it.

Get to know the Java persistence standard based on Hibernate and learn how to use JPA to store and manage Java objects in a relational or NoSQL database.