Spring MVC application (data binding - custom type converter, data format, data verification)

1, Ask questions When spring MVC encapsulates custom type objects, JavaBean s are bound to the data submitted by the page one by one. Here's what you need to know: 1) all data submitted by the page are strings 2) attributes in JavaBean s, such as Integer age; When binding data, the following oper ...

Posted by saeed42 on Wed, 05 Feb 2020 22:31:22 -0800

Group Programming Skystair L2-019 quietly watched (25 points) (java)

Group Programming Skystair L2-019 quietly watched (25 points) (java) Sina Weibo has a "quiet focus". A person that a user quietly Watches does not appear on the user's attention list, but the system will push the Weibo published by the person that he quietly watches to the user.Now let's do ...

Posted by gergy008 on Wed, 05 Feb 2020 18:11:28 -0800

Alibaba Java Development Manual Codes Effective Details-An Analysis of the Grinding Null Pointer Problem

1 Leader Say nothing but read the manual guidelines first The manual has helped us summarize common problem scenarios, but we still need to dig into the null pointer problem in order to get it right. 2 What is the null pointer in the world? 2.1 Official Resolution A null is passed in when the app ...

Posted by leatherback on Wed, 05 Feb 2020 16:45:04 -0800

JDBC development steps

JDBC development steps 1. Registration driver ---Tell the JVM which database driver to use 2. Get connected ---Use the classes in JDBC to complete the connection to the MySQL database 3. Get statement execution platform ---Get the executor object of the SQL statement through the connection object ...

Posted by scross on Wed, 05 Feb 2020 06:10:11 -0800

Java multithreaded Semaphore synchronization classes CountDownLatch and Semaphore

Semaphore synchronization refers to the coordination of thread execution sequence by transferring synchronization semaphores between different threads. CountDownLatch is based on time dimension, semaphore is based on signal dimension. 1: Execution time based synchronization class CountDownLatch For example, for the existing three servers, it is ...

Posted by activomate on Wed, 05 Feb 2020 04:23:47 -0800

Alicloud OSS upload / download and SMS verification code

(1) : you must first open related services on alicloud OSS. For details, please refer to this link: https://help.aliyun.com/document_detail/31883.html?spm=5176.10695662.1996646101.searchclickresult.5ceb3ee82NzMq7&aly_as=WhUj5kPK Or for video address, please refer to this link: http://cloud.video.tao ...

Posted by stick_figure on Wed, 05 Feb 2020 03:42:59 -0800

ProcessFunction: the lowest level API of Flink

Some operators and functions mentioned above can perform some time operations, but cannot obtain the current Processing Time or Watermark timestamp of the operator, which is simple to call but relatively limited in function. If you want to get the time stamp of Watermark in the data flow, or shuttle bac ...

Posted by eddjc on Wed, 05 Feb 2020 02:21:22 -0800

javaSE learning notes - day 25 multithreading II. GUI overview

javaSE learning day 25 java knowledge Multithreading (single design mode) Singleton design pattern: ensure that the class has only one object in memory. How to ensure that a class has only one object in memory? (1) Control the creation of classes. Do not let other classes create objects of ...

Posted by amithn12 on Wed, 05 Feb 2020 00:38:49 -0800

MyBatis interface binding and multiparameter

Article Directory MyBatis Interface Binding Scheme and Multi-parameter Passing map mode for multiparameter transfer Interface Binding Interface for multiparameter delivery MyBatis Interface Binding Scheme and Multi-parameter Passing In addition and deletion checks of MyBatis, it is found that ...

Posted by TRB on Tue, 04 Feb 2020 19:39:38 -0800

Android About AIDL Communication, RemoteCallbackList Implements Server Callback Client

Android Interface Definition Language (AIDL) The Android Interface Definition Language (A IDL) is similar to other interface languages (IDLs) you may have used.It allows you to define programming interfaces that are recognized by both clients and services so that they can communicate with each other ...

Posted by BPWheeler on Tue, 04 Feb 2020 19:33:10 -0800