Components represent various graphical entities that can be displayed on the screen, while components in Java are abstract concepts and are actually classes, such as components "servlet", "jsp" and "javabean" etc. are all java classes.
This article mainly introduces to you what components are in Java. I hope it will be helpful to friends in need!
Components represent various graphical entities that can be displayed on the screen. A component is an object of a Component subclass. As we have seen, the JFrame window is a component, but does not contain other subclasses.
To put it simply, java is actually a class.
Components are just abstract concepts. In layman’s terms, some classes that comply with certain specifications are combined to form a component. It can provide certain functions.
Take J2EE as an example, servlets, jsp, javabeans, and ejb are all components. But in fact they are all classes, but they have their own special regulations.
For example, take a javabean:
javabean is also a class, but if your class wants to become a javabean, you must add variables (such as xxx) in your class. Two functions, getXxx() and setXxx(), and there must be a parameterless constructor in the class.
With these is JAVABEAN.
You have to ask why there are these regulations. At present, we can only say that if components want to use each other, there must be a specification to restrict them. You will understand it better when you have more contact with me.
Related recommendations: "Java Tutorial"
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