programmer group

How View works draw

1, Overview Compared with the previous measurement, the layout of the picture here is very simple The general steps are as follows: 1. Draw background (canvas) 2. Draw yourself (onDraw) 3. Draw children(dispatchDraw) 4. Ondrawscrollbars The following is the specific code of draw, which is divided into six parts, but the gradient edge is not necessarily there, so it is simplified to the above four steps. public void...

programmer group

Java for Quick Sort and Three-way Quick Sort

Quick Sort Ideas Select an element in the array (usually the first element of the array) as a reference object, arrange elements in the array smaller than the reference object to the left of the array, and elements larger than the reference object to the right of the array. Quick sorting steps With the first element a[0] of the array a[N] as the reference object, two pointers i and j are set to point to the positions of the array...

programmer group

Finding Data Structure Experiments Part Three: Tree Species Statistics

Finding Data Structure Experiments Part Three: Tree Species Statistics Time Limit: 400MS Memory Limit: 65536KB Submit Statistic Problem Description With the application of satellite imaging technology, natural resources research institutes can identify each tree species.Write a program to help researchers count the number of each tree and calculate the percentage of each tree to the total. Input Enter a set...

programmer group

A simple example of using Guava's eventbus to complete asynchronous events

Guava's Event Bus library is an implementation of the event publishing subscription model, enabling us to decouple our modules and domain boundaries well in the domain-driven design (DDD) by the nature of weak references to events.The following are examples of common asynchronous events: 1. Declare asynchronous processing classes inside configure @Bean public AsyncEventBus asyncEventBus(){ return new...

programmer group

[operator overloading] SDUT 1272 - Practice 10 of object-oriented programming (operator overloading)

Problem Description Define a Complex class, overload operator "+", so that it can be used for Complex addition. The two operands involved in the operation can be class objects, or one of them can be an integer in any order. For example, c1+c2, i+c1, c1+i are all legal. (where i is an integer, c1 and c2 are a Complex number), the program realizes the sum of two Complex numbers, the sum of integer and Complex...

programmer group

Linux file management mkdir

mkdir create directory Original meaning of order make directories Command format mkdir [options] [directory name] Command function Lists the creation directory. Common parameters -M -- mode = mode, set permission < mode > (similar to chmod), instead of rwxrwxrwx minus umask -P -- parents can be a path name. At this time, if some directories in the path do not exist, plus this option, the system will automatically...