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catalogue 1, Construction of pseudo distributed 1.1 introduction to pseudo distributed mode 1.2 platform software description 1.3 requirements for building pseudo distributed environment 1.3.1 environmental requirements 1.3.2 firewall shutdown confirmation 1.3.3 configuration mapping 1.3.4 ensure that ssh is valid for password free auth ...

Niu Ke's Diary (December 6, 2021) Title: Which of the following modifiers modifies a variable that is shared by all objects generated by the same class () public private static final Resolution: Correct answer: C When static modifies a field, it will certainly change the way the field is created (each static modified field has only on ...

1) Problem motivation and usage scenarios In a recent project, the required function is to use the mouse to add nodes (the position where the mouse clicks is the node coordinates), and the point coordinates can be displayed visually and dynamically after being added. 2) Problem solving process In ordinary python drawing, my commonly used too ...

Python Learning Notes python language base variable Variable name specification: 1. Can only consist of letters, numbers and underscores 2. Cannot start with a number 3. You cannot name a Python built-in key data type int plastic float float str Character string bool Boolean tuple tuple list list set aggregate ...

4. Data processing and jump In the previous section, we learned about controllers and Restful style operations Mad God says spring mvc03: RestFul and controller Now let's take a look at spring MVC parameter receiving processing and result jump processing! 4.1 result jump method 4.1.1ModelAndView Set the ModelAndView object and jump to the ...

Virtual functions and virtual function tables Virtual function: a member function decorated with virtualImpact of virtual function on class: add a pointer, 32-bit 4 bytes, 64 bit 8 bytesVirtual function table: a pointer that stores the first addresses of all virtual functions Virtual functions and polymorphisms Polymorphism: different results ...

Online problem handling - feign call error Business scenario: Service 1 invokes service 2 through Feign. In the test phase, everything is normal and there is data loss online (to avoid simple reproduction of sensitive local). Errors are reported as follows: 2021-12-04 13:47:47.774 DEBUG 29480 --- [io-10011-exec-1] .w.s.m.m.a.ServletInvocableH ...

Preface *** The Runnable interface we used often before cannot return results or throw out exception classes that can be checked. To make up for this, there's the Callable interface, which we're going to cover in this blog. Callable interface @FunctionalInterface public interface Callable<V> { /** * Computes a result, or ...

This article introduces the purpose of the main commands in Dockerfile FROM Specify the basic image. The recommended method is image:tag. Specify it precisely. Note: you can use multiple FROM, which will build multiple mirrors. For example, I want busybox and nginx at the same time. I can write this FROM busybox:latest FROM nginx:latest ...

Note: the data comes from Blue bridge cloud course( https://www.lanqiao.cn/ ) , interested partners can go to the official website to learn. Here is the information compiled by Xiaobian after his study. If there is any error, please leave a message for discussion. Thank you! summary Exception refers to all kinds of unexpected conditions that ...