Category:OOP

  • Six principles of object oriented

    Time:2020-3-28

    Nowadays, the mainstream programming languages are basically object-oriented. Such as C, C + +, Java. When we use it, we have constructed classes one by one. However, there are many problems in the design of inner or outer classes, which make it difficult to maintain the process oriented logic even though it is an object-oriented […]

  • Java basic learning summary – Super keyword

    Time:2020-3-27

    1、 What is super? It is a referential variable, a reference to a direct parent object, which is used to refer to a parent object in a subclass. Two, application 2.1 application scope It can only be used in constructors and instance methods of subclasses, but not in class (static) methods of subclasses. Reason: Super […]

  • Exception and error

    Time:2020-3-26

    What’s the difference between exception and error Exception and error both inherit the throwable class In Java, only instances that inherit the throwable class can be thrown or caught Inheritance relationship Exception The unexpected situation that can be expected in the process of program running can be captured and handled in the program. It means:This […]

  • Project module — 1. Implementation of verification code function

    Time:2020-3-25

    Introduction: In the Java Web project, a verification code is randomly generated at the back end, drawn into an image, and two interference lines are added to the image and sent to the browser for the user to use. The content of this blog includes the logical steps of function implementation, Java implementation code, and […]

  • Blog assignment of unit 1 of Beihang OO (2020)

    Time:2020-3-24

    Blog assignment of unit 1 of Beihang OO (2020) Catalog Blog assignment of unit 1 of Beihang OO (2020) Analysis of program structure based on measurement Homework 1 Code metrics UML class diagram Analysis of advantages and disadvantages Homework 2 Code metrics UML class diagram Analysis of advantages and disadvantages Homework 3 Code metrics UML […]