IO flow in Java

IO stream, that is, the technology used to manipulate the content of a File. So before we talk about IO streams, we need to know about the File class. 1, File file class 1. File class introduction File is used by Java to represent files / folders (directories). Files / folders on the hard disk can b ...

Posted by pendelton on Sun, 14 Jun 2020 09:59:29 +0200

Social security card information reading

In recent years, with the popularization and development of medical intelligent self-service terminal, the unattended self-service terminal realizes the patient's independent appointment, registration, report query and other services. It is not only convenient for patients to see a doctor, but also i ...

Posted by daftdog on Fri, 12 Jun 2020 12:29:19 +0200

Xcu -- data visualization -- Experiment 2

Data visualization experiment 2 preface Through pandas in python, the experiment is completed with bar graph, bar graph and line graph. Title Requirements 1. "Tourism annual data. xls" and "tourism statistical data. csv" are tourism statistical data from 2009 to 2018, includ ...

Posted by shergar1983 on Fri, 12 Jun 2020 08:44:49 +0200

Buffer stream of IO stream

Article catalog Buffer stream of IO stream 1. Overview of buffer flow 2. Byte buffer stream `BufferedInputStream/BufferedOutputStream` Efficiency test 3. Character buffer stream Unique methods 4. Exercise - text sorting Please restore the text information order case analysis Case realization ☆ ...

Posted by ardyandkari on Fri, 12 Jun 2020 06:15:55 +0200

Android Studio package H5 project (2020 version)

I'm the catalog 1, Download Android Studio 2, New Android project 3, What a complete android app needs 1. Be able to access the network 2. Be able to go back, just like App 3. Customize the App icon, not a default Android robot 4. Modify application name 5. Change the color of the main interface to ...

Posted by bob_rock on Thu, 11 Jun 2020 09:22:55 +0200

Basic implementation of ActionBar and ToolBar under API29

Based on Android studio to customize the top menu bar -- the basic implementation of ActionBar and ToolBar Custom ActionBar Custom ToolBar Custom ActionBar ActionBar is a window function to determine the user's location, and it can provide the user's operation and navigation module. Using Action ...

Posted by EagerWolf on Sat, 06 Jun 2020 12:30:22 +0200

MySQL library building, table building, constraints building and storage engine

1. MySQL Library and Table Building 1. Create a database Creating a database is a block area on the system disk used for data storage and management. If an administrator creates a database for users when setting permissions, it can be used directly. Otherwise, you need to create the database yourself. Grammar Format: CREATE DATABASE [IF NOT ...

Posted by Horatiu on Wed, 03 Jun 2020 18:20:45 +0200

Android uses GridView to load (weak reference) network pictures asynchronously (click to view)

Android uses GridView to load (weak reference) network pictures asynchronously (click to view) In the current Android development, more and more app s use the album function of Android. Using the album will use GridView to load pictures, but when loading a large number of pictures, there will be a black screen because the loading process is ...

Posted by VirtuosiMedia on Tue, 02 Jun 2020 17:57:27 +0200

Day 76: Scrapy analog login

by Leisure Want to crawl website data? Log in first! For most large-scale websites, the first threshold to crawl their data is to log in to the website. Now please follow my steps to learn how to simulate landing on the website. Why do I log in? There are two kinds of websites on the Internet: need to log in and don't need to log in. (this ...

Posted by sousousou on Mon, 01 Jun 2020 08:43:33 +0200

How do I use Lock? What is the difference between Lock and synchronized?

  Lock   It's like a synchronization block, java.util.concurrent.locks.Lock Is the thread synchronization mechanism. However, locks are more flexible and complex than synchronous blocks. Because lock is an interface, you need to use one of its implementations to use lock in your application. ReentrantLock is one such implementation of ...

Posted by greedyisg00d on Wed, 27 May 2020 07:09:42 +0200