Keywords: object-oriented programming, abbreviation OOP, object (Object), class (Class), five basic features of Java object-oriented programming: 1) Everything is an object. Everything is an object. 2) a program is a bunch of objects telling each other what to do by sending message. Program is a group to tell how to do with each other by passing messages. 3) Each Object Has Ite OWN MEMORY MADE UP OF Other Objects. Each object uses other objects to create their own storage space. 4) Every Object Has A Type. Each object has a type. 5) All Objects of a Particular Type Can Receive The Same Messages. All objects belonging to the same class can accept the same message.
Objects will provide services When you develop a program or analyze a program design, the best way to understand the object is to treat them as a "service provider", and the program itself provides services to the user, and it provides services through other objects To do your job, your task is to make (or find out where you can find the problem from the present code library) a group to resolve the problem. Objects (CLAS) concepts About these 2 concepts In fact, we have come into contact with our previous junior high school biological textbooks. Many books are now explained in explaining this 2 concepts, often borrowed without life, such as cars, graphics, etc. to explain. The concept of objects and classes is actually borrowed from biology, so there are two basic concepts of Object, Class. Class is a biological species in biology, and Object is a specific per individual. Object is the original meaning "things", or "creatures", its original intention is something that is life, so there are attributes, action, state, and so on. I think that if we can use something with life to help make more understanding. Birds / | / Sparrow Parrot Eagle Access Privilege Control Private, Public, Protected, and (Default). Publicity refers to subsequent definitions can be used by anyone. Private cannot be accessed in addition to the creator and class of the class. Protected keywords are like Private, which distinguish between inherited classes only access protected objects, but cannot access the private object. By default, represents Package Access Permissions, and the class belonging to this package (package) can access a member of the class belonging to this package.
