the H5 side sends a request and then cannot get the data. I looked at the request in the background dispath log and found that the request had been received, the data had been queried, and the code ran out. And I didn t report it wrong. and I can re...
String s1 = new StringBuilder().append("").append("").toString(); System.out.println(s1.intern() == s1); String s2 = new StringBuilder().append("ja").append("va").toString(); System.out.println(s2.intern() == s2); ...
I know that message queues can cut the front and fill the valley message queue sharpening is easy to understand. Message queuing can limit traffic when a large number of requests are sent. Protect the back end. but how to understand filling grain ...
recently read "Java concurrent programming practice, " in Section 4.4.1, there is an example: suppose we need a thread-safe List, that needs to provide us with an atomic "put-if-absent " operation. And two implementations are provided: A non-thread...
when deploying a web project in multiple environments, you can set the packaged configuration file by specifying mvn package -Pdev , but how do you specify which environment configuration file to use when deploying the service directly with tomcat? the...
whether the formId sent by Mini Program template message follows the user, that is, whether the formId generated by user A can be used to send it to user B ...
the constructor with String of the JFrame class is obviously public, so why not inherit it to the subclass? import javax.swing.*; public class test extends JFrame { public test() { TODO } public static void main(String[] ar...
NIO is suitable for architectures with a large number of connections and short connections (light operation), such as chat servers, and concurrency is limited to applications AIO is used in architectures with a large number of connections and long con...
how to broadcast their messages to specific groups in the websocket of springboot, just as we usually chat in groups. My messages in this group cannot be received to people in other groups ....
log4j:WARN No appenders could be found for logger (org.springframework.web.context.support.StandardServletEnvironment). log4j:WARN Please initialize the log4j system properly. log4j:WARN See http: logging.apache.org log. for more info. the one who...
I took a look at the payment bar codes of Alipay and Wechat. They are both in the format of 4-4-4-6 (the first two bits remain unchanged) and can be generated offline. They should be time-stamped and then encrypted. Is there any algorithm for writing enc...
are there any open source middleware products that provide traffic marking and traffic distribution? that is, when a http request comes, you can route the request to the specified machine or environment according to the information of various dimension...
remove error: id to load is required for loading in SSH framework ...
springboot multi-module project, in which web project is packaged into jar to run, web project relies on tool module xx.jar xx.jar to read data files through ClassLoader.getSystemResourceAsStream ( "xx.txt "), running tool module alone can run but web ...
< H2 > NewFile.java < H2 > private File configurationFile; public NewFile(File file){ this.configurationFile = file; } public void newFile() throws IOException{ if (!configurationFile.exists()) configurationFile.createNewFile(); ...
I use tomcat to start a project on win10. Local computer access is easy. Sending url to a mobile phone will not open it. I would like to ask how to enable the external network to access local projects ....
I learned the PrintWritere class and the Scanner class , the assignment is to turn a minor line style java program into a line end style , or to replace all the substrings of "n { " in a java text file with "{ " , but the Scanner class does not rea dna...
Why does the following program print false? the book says that java uses the same instance of String objects with the same content so why are references not equal? public class test { public static void main(String[] args) { String s1=&qu...
how to parse the excel table and spell it into SQL statements according to your own needs? is there a big god to give a template ...
threadlocalmap uses open addressing to resolve hash conflicts, but the design of node in threadlocalmap is still . static class Entry extends WeakReference<ThreadLocal<?>> { ** The value associated with this ThreadLocal. * ...
cannot find the method 3if (node.checked) 2. Press Ctrl+F to search for TreeStore.prototype.getCheckedKeys 3. Change if (node.checked) to if (node.checked | | node.indeterminate) as shown below: ...
WeChat Mini Programs s authorization to obtain user information does not allow pop-up window access, but must be obtained by button. so, I want to set a common template (or module?) in the mpvue framework. ), it is easy to place the button that trigg...
I have multiple spring boot projects, and I want to extract the common code and configuration of these projects into a common configuration. For example, @EnableAspectJAutoProxy public class DefaultConfig {} I want all projects to open AOP, but I do...
when a paragraph of text is selected with the mouse, the background of the text turns blue. how to deselect it with JS or JQ? Note: not to disable the selected text at first, but to uncheck the selected one. ...
problem description write crawler code with vscode on mac, some of which try to use pool to crawl, but once you add the pool-related code, the program will not work properly, comment out the pool-related code and you can crawl the picture normally. ...