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Java class related problems
2022-02-03 01:13:29 【CSDN Q & A】
What is the meaning of the class name as the return value
The output of this is that students learn
It is the same as this result
I can't figure out what the meaning of class name as return value is
He is direct new Student Isn't class more labor-saving
Class names are easy to understand as methods , As a return value, I always feel strange
Words , The process of creating objects is just opening up space , Why don't you instantiate when you return a value
Refer to the answer 1:
You this getStudent The overall meaning of the method is
// Create a return Student Object method public StudentgetStudent(){ // Create a Student object s Student s=new Student() // Return to new object s return s}
Refer to the answer 2:
Refer to the answer 3:
It depends on the specific scene
This really doesn't make any more sense in your code
If you write like this , You can make sure you get the same... Every time Student
public Teacher{ Student student = null; public Student getStudent(){ if (student == null){ student = new Student(); } return student; }}
Refer to the answer 4:
Refer to the answer 5:
Take a scene , Generally, this return type is an interface ,Teacher What is returned is the implementation class of this interface , As for what is written in this implementation class, you don't have to worry about , You just call it according to the method provided by the interface , polymorphic .
Programming is a multi-party project , When you call a third party provided sdk Or interface , You don't need to focus on how others achieve , Just bring it here .
Refer to the answer 6:
Refer to the answer 7:
This is an exercise , I'm teaching you how to treat a class as a parameter or return value
Just like you learn math in primary school , It must be from 1+1 Start learning
You can't feel like learning 1+1 It's no use
Refer to the answer 8:
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author[CSDN Q & A],Please bring the original link to reprint, thank you.
https://en.primo.wiki/2022/02/202202030113267951.html
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