abstract class in java

Java abstract classes differ from interfaces:Abstract class and interface are the two mechanisms in the Java language to support the definition of a class, and it is precisely because of the existence of these two mechanisms that it gives

turn from: in-depth understanding of Java interfaces and abstract classesAbstract is one of the most important features of object-oriented programming. In Java, there are two ways to embody the abstraction of OOP: interfaces and abstract classes. There are too many similarities, and there are too many different places.

be decorated with the abstract keyword. If a class contains abstract methods, it is called an abstract class, and the abstract class must be decorated with the

Java Abstract class In object-oriented concepts, all objects are depicted by classes, but conversely, not all classes are used to depict objects, and if a class does not contain enough information to depict a specific object, such a class is an

implementation of the situation.3, achieve multi-inheritance effect.ExampleAn example of a abstract class in the JDK are Abstractmap, which is part of the collections Framework. Its subclasses (which include HashMap, TreeMap, and Concurrenthashmap) share many methods (including get, put, IsEmpty, CO Ntainskey, and Containsvalue) that Abstractmap defines.An example of a

interest rates. Therefore, the interest rate calculation method is not implemented in this parent class, instead, it is postponed to the subclass to implement the */protected abstract double getInterestRate () ;}} interface: a set of abstract methods and constants. That is to say, the interface can only have Abstract

Java interface and abstract class differences 1. OverviewA software design is good or bad, I think to a large extent, it depends on its overall structure, and this whole structure is your abstract framework of the entire macro-business business, when the high-level abstraction layer representing business logic is reaso

Original: http://blog.csdn.net/sunboard/article/details/38318231. OverviewA software design is good or bad, I think very much depends on its overall architecture, and this overall architecture is in fact your entire macro business of the abstract framework, when the high-level abstraction layer representing business logic is reasonable, you need to consider the underlying detailed implementation of some algorithms and some detailed business implementa

It turns out that you are such a JAVA [03]-inheritance, polymorphism, abstract class, java Polymorphism1. Inheritance In Java, the inheritance uses the keyword extends, which is slightly different from the C # syntax.1. Subclass Constructor

Abstract the conceptual abstraction of a class is a special method: it has only declarations, but no concrete implementations. The declaration format for an abstract method is: abstract void Fun ()//No curly braces means no bodyAbstract methods must be decorated with the abstract