Classes, fields, methods, constructors, and objects are the building blocks of object-based Java applications. This Java tutorial teaches you how to declare classes, describe attributes via fields ...

Classes and objects in Java must be initialized before they are used. You’ve previously learned that class fields are initialized to default values when classes are loaded, ...

Java 25 introduces Compact Object Headers (JEP 519), delivering up to 30% CPU savings and reduced memory usage for applications with small objects. This user-friendly feature compresses object headers ...

Java currently supports only two types of value: primitives and object references. Project Valhalla extends this by introducing inline classes which are a new form of type that exhibit some ...

Finally, we learned that everything in Java is an object, except primitive data types. Because so much of this programming style involves objects and classes, we will now look at each of these ...

However, the Java Platform provides a data structure that greatly simplifies the use of reference objects like this, called the java.util.WeakHashMap class. WeakHashMap works exactly like a hash ...

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 ...

Of course, Java object serialization is only half of the job. The other half is Java object deserializtion, which we accomplish with the FileInputStream and the ObjectInputStream. The first step to ...