Java programming ideology notes

• By providing constructors, the class designer can ensure that each object is initialized.
• This policy is appropriate because the garbage collection mechanism also has overhead.
• Finalize () is required because free () is used in the C language when memory is allocated.
• The domain name is reversed to obtain a unique package name. The hierarchical file structure is used to solve the project file management confusion problem and the namespace problem.
• Use inheritance to express the relationship "is-A is a", and use a combination to express the relationship "has-A has.
• Use inheritance criteria: Determine whether to transform the new class to the base class.
• Realize polymorphism through dynamic binding, send a message to the base class object, and let the object determine what to let the export class do.
• The meaning of the interface: establish the protocol between classes; completely decouple; Combine multiple interfaces to achieve multi-inheritance without burdens.
• The internal class can access all the members of its peripheral object without any special conditions.
• Java uses a combination of internal classes to replace multiple inheritance of C ++.
• Container provides a complete method of holding objects to solve complicated data structures.
• With generics, you can prevent objects of the Error Type from being placed in the container during compilation.
• The job of the exception handling program is to restore the program from the error State so that it can either run in another way or continue to run.