Abstraction in Java is a fundamental concept in object-oriented programming (OOP) that focuses on hiding the complex implementation details and exposing only the necessary features of an object. This allows developers to interact with objects at a higher level without needing to understand the intricate workings behind them.

In Java, abstraction can be achieved through abstract classes and interfaces. An abstract class can contain both abstract methods (without implementation) and concrete methods (with implementation). This allows subclasses to inherit the abstract class and provide specific implementations for the abstract methods. Interfaces, on the other hand, define a contract that implementing classes must follow, ensuring that they provide specific functionalities.

The primary goal of abstraction is to reduce complexity and increase efficiency by allowing programmers to work with simplified representations of complex systems. This is particularly useful in large applications where managing intricate details can be overwhelming.

For more detailed examples and implementations of abstraction in Java, you may refer to the relevant documents that discuss OOP concepts and their applications in Java ¹²³.