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Knowledge summary of open source web framework django (10) Asynchronous scheme Celery Producer consumer design model reflection: What's wrong with the following two lines of code? CCP().send_template_sms(mobile, [sms_code, 5], 1) return JsonResponse({'code': 0,'errmsg': 'ok'}) Question: Our code is executed synchronously from to ...

spring is actually a container, and IOC is one of them to collect our objects IOC create object User public class User { private String name; public User(){ System.out.println("User Nonparametric structure of"); } public String getName() { return name; } public void setName(String name) { ...

Django model layer Today, let's talk about Django's model layer. Django provides an abstract model ("models") layer to build and manipulate the data of Web applications. 1. The concept of model: 1. Model introduction The model can accurately and uniquely describe the data. Contains important fields and behaviors for stored da ...

1 install VMware virtual machine The default installation is OK. If you change the installation location, remember to use the VMware installation directory after the changed location 2. Install RedHat red hat system 2.1 virtual machine settings: Create a new virtual machineCustom (Advanced)Select virtual machine hardware compatibility ...

Don't say much about the description. Go directly to the figure above: See the output? Why is the time difference between the first time and the second time so much? Let's think about it together. We can also look at the conclusion first and then look back at the analysis Note: not only the second time, but every time after the first t ...

What is a thing Things can be regarded as a unit composed of several operations on the database at a time. When we are developing projects at the enterprise level, we are faced with an operation of business personnel, but actually a collection of multi-step operations to read and write to the database. Because data operations are executed ...

Thread pool [understand] Status of the thread NEW      Threads that have not yet started are in this state.   RUNNABLE      The thread executing in the Java virtual machine is in this state.   BLOCKED      A thread that is blocked and waiting for a monitor lock is in this state.   ...

Write before: This chapter mainly talks about the knowledge of threads. Thread is essentially different from other chapters. The reason is that thread allows you to do multiple things at the same time and execute some tasks concurrently. Then let's explore the important knowledge in this chapter. catalog: 1. What is the function of futuret ...

  preface This article will explain the offset analysis function + over() through an example 1, Concept of offset analysis function lag(col,n,default): used to count the value of the nth row up in the group. The first parameter is the column nameThe second parameter is the nth line up (optional, not filled in, default to 1)The third ...

5. Collection thread safety Thread unsafe demo for collection ArrayListpackage com.codetip.codejuc.juc.conllections; import java.util.ArrayList; import java.util.List; import java.util.UUID; public class ThreadArrayList { public static void main(String[] args) { List<String> list = new ArrayList<>(); for ...