Programmer Think

1, Array 1.1 array introduction An array is a container for storing data with a fixed length. The data types for storing multiple data should be consistent. 1.2 definition format of array 1.2. 1 first format Data type [] array name Example: int[] arr; double[] arr; char[] arr; 1.2. 2 second format Data type array n ...

Tell the blogger @ of station b to meet the crazy God all the way Java basic video 1, User interaction Scanner 1. Realize the interaction between programs and people. java provides us with a tool class, so we can get the user's input, and we can get the user's input through the Scanner class. 2. Basic grammar: Scanner s = new Scanner(System. ...

concept 1. java objects Object header (Object header) 12byte. Object header is composed of Mark word (8byte) and Klass pointer (turn on pointer compression size is 4 byte, pointer to object's metadata, pointer to template of method area class class class). Aligned bytes (consisting of instance data of the object and byte alignment. Because ...

OpenJDK System. Analysis of loadlibrary source code System.loadLibrary is used to inform the JVM to load Native so. After so is loaded successfully, you can see that so has been loaded into memory in / proc/self/maps. Students familiar with system layer development can guess that this is basically equivalent to dlopen/LoadLibrary call. Next, l ...

Look it up in the dictionary and use the Python dictionaryAfter learning the list and tuple, they are arranged in order, so you can use the index to get the value. What this blog wants to learn is the dictionary. As can be seen from the above, the dictionary can't get the value according to the index, that is, there is no sequential and non seq ...

As shown in the following code, a is a local variable in the stack frame. When a = null, because a acts as a GC Root, a is disconnected from the instance new Test(), so the object will be recycled. publicclass Test { public static void main(String[] args) { Test a = new Test(); a = null; } } 2. The object referenced by the ...

catalogue 1) Module installation and import 2)os.getcwd() 3)os.listdir(path) 4)os.walk(path) 5)os.path.exists(path) 6)os.mkdir(path) 7)os.rmdir(path) 8)os.path.join(path1,path2) 9)os.path.split(path) 10)os.path.dirname(path) 11)os.path.basename(path) 12)os.path.isdir(path) 13)os.path.isfile(path) 14)os.path.getsize(path) The os ...

In life, when we write java code, we usually try Catch wraps around the code block where exceptions may occur. However, if a java project is too large and a bug occurs at the same time, it is not conducive for us to check the error. So we can use email, write an email tool class ourselves, and use try During catch processing, you can use the ...

2021SC@SDUSC catalogue 1, WindowSize() function 2, SetWindowSize() function 3, WindowSizeLimits() function 4, IsWindowFloating() function 5, SetWindowFloating() function 6, Maximize window() function 7, SetWindowClosingHandled() function 1, WindowSize() function The code is as follows: func WindowSize() (int, int) { if w := uiDri ...

Django background improvementList page display content modificationIn the last blog, the list data display was realized, but only one column was displayed, and the column title was English. This blog first solved this problem. Modify admin. In the blog folder Py file, the code is as follows:from django.contrib import admin from blog.models imp ...