Today I am reviewing the Java knowledge I learned this semester, and I will talk about some basic knowledge of Java here
When you first start learning the Java programming language, you will quickly encounter three important concepts: class encapsulation, inheritance, and interfaces. These concepts are at the heart of Object-Oriented Programming (OOP), and they help create maintainable, reusable, and extensible code.
First, let's look at class encapsulation. In Java, encapsulation is the process of combining data and behavior in one unit. Such units are called classes. Classes encapsulate data and methods so that data cannot be accessed externally. This encapsulation mechanism provides data security and better code modularity, while also allowing modifications without affecting other modules.
Next, let's look at inheritance. Inheritance is a mechanism that allows you to create a new class and inherit all the properties and methods from the existing class. Inheritance provides the ability to reuse and extend code. Subclasses can inherit all the properties and methods of the parent class, and can also add their own properties and methods. Inheritance also allows you to create a hierarchy where higher-level classes have common properties and methods, and lower-level classes have specific properties and methods.
Finally, let's look at the interface. An interface is a special class type that defines a set of methods but does not implement them. The interface provides a contract, so that the class can follow the specification of the interface and have the same behavior. Interfaces allow you to create generic code that can be used with any class that implements the interface. Interfaces also allow you to create the ability of multiple inheritance, which in Java can only be achieved by implementing multiple interfaces.
To sum up, encapsulation, inheritance, and interfaces are important OOP concepts in the Java programming language. Encapsulation provides data security and better code modularity, inheritance provides the ability to reuse and extend code, and interfaces provide common code and multiple inheritance capabilities. Understanding these concepts and applying them correctly to your code will make us a good Java programmer.