I am a java rookie, ask some rookie questions? use spring-boot to develop projects, spring-data-jpa to access databases, there are many fields in the database, but only some of them are used by the client, while the data needed by the background is ...
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<dependency> <groupId>org.springframework.boot< groupId> <artifactId>spring-boot-starter-thymeleaf< artifactId> < dependency> add this and pom.xml will report an error. What s ...
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protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { resp.setContentType("text html;charset=gb2312"); PrintWriter out = resp.getWriter(); out.println("<htm...
how do they compare their advantages and disadvantages? I feel that ConcurrentHashMap will have higher performance, after all, the built-in ...
java code, using mongodb database, business scenarios are several items, which can be purchased at the front desk, and the backend may modify inventory or online and offline goods at the same time. How to design to ensure that dirty data will not be gen...
about the problem of Java, we usually get the results by using the stack as a keyword to the search engine. :) the problem encountered this time is a bit interesting, and the procedure is very simple, so just ask a question. what s wrong with the fol...
how does SpringBoot access the page? I returned the string "login " at controller. It didn t access the login.html page. Do I need to add thymeleaf dependencies? ...
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for example, how to completely restructure a project that is being iterated for a long time? it takes a long time to ReFactor a completed project. ...
see the following changes in Android P Behavior Changes FLAG_ACTIVITY_NEW_TASK requirement is now enforced With Android P, you cannot start an activity from a non-activity context unless you pass the intent flag FLAG_ACTIVITY_NEW_TASK. If you attem...
tb_user (user information) id tb_article (article information) id, foreign key user_id-> tb_user.id tb_comment (comment information) id, foreign key user_id-> tb_user.id query the top 5 users of the latest article or comment. order by tb_article.cre...
: class Test{} object Driver extends Test{ } : abstract Fruit{ val name :String val color :String } object Fruit{ object Apple extends Fruit("apple","red") val menu=List(Apple) } question: (1) Why object in scala can al...
spring mvc uses the @ PostMapping,url path similar to this: xxx yyy {uid} runs using the jetty container. when postman simulates a request, the path must be xxx yyy {uid} ? uid=11111 to get the request; but using tomcat only needs xxx yyy 11...
Now, I begin to learn vert.x. At first, I tried to define a function that can work. However, my current implementation gives me the following error: when I run the program for the second time 22, 2018 3:29:23 io.vertx.core.http.impl.HttpServerImp...
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1. Write the parameters of the form directly in the formal parameters of the corresponding method of Controller public String addUser1 (String username,String password) and bind the request parameter public String addUser6 (@ RequestParam ( "username...
existing requirements for ListView item to support gesture zooming in and out, trying some of what is said online is unsuccessful, how should it be realized? ...
^ _ [Amurz] {2jue 10} $ is there a problem with this regular expression? see that no one writes that on the Internet. [Amurz] is all of [a-zA-Z]....
< div> < div> < body> < html> A simple page is centered so that the picture inside can be scrolled. Then I manually use scale on the page to enlarge the picture, the parent element of the enlarged image content can...
for example, 0386 will be displayed as 386 can not be displayed even if the tool is converted to xls ....
var formData = new FormData (); formData.append ( "image ", document.getElementById ( "FileUpload "). Files [0]); $.ajax ({) url: url, type: post , data: formData, cache: false, ** *falseContent-Type * contentType: false, ** * falsejQuery formda...
call in actions commit( mapSet ,map1); mutations is mapSet:(state,mymap)=>{ state.mymap=mymap; }, where map1 is an object, that is, the parameter passed in is an object, and an error will occur when it is ca...
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