The static method RequestContextHolder.getRequestAttributes() to get the request attributes in the current thread

RequestContextHolder.getRequestAttributes()It is a static method used in the Spring framework to obtain the request attributes in the current thread. It is commonly used in web applications to access contextual information about the current request. In Spring's web application, each request will have a corresponding request context, which contains the relevant information of the request, such as request header, parameters, session, etc.

This method returns a RequestAttributesobject containing all the properties of the current request. It is an abstract interface, and Spring provides different implementations to suit different application scenarios.

RequestContextHolder.getRequestAttributes()A common usage in Spring web applications is to access information about the current request in code in the service layer or other non-web layer. For example, you may need to obtain the information of the currently logged-in user, request parameters, etc. in the business logic.

Here is a simple example showing how to use RequestContextHolder.getRequestAttributes():

import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;

public class MyService {
    
    

    public void doSomething() {
    
    
        // 获取当前请求的属性
        RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();

        if (requestAttributes != null) {
    
    
            // 获取请求参数
            String parameterValue = (String) requestAttributes.getAttribute("parameterName", RequestAttributes.SCOPE_REQUEST);

            // 在这里可以继续处理逻辑
        }
    }
}

It should be noted that it RequestContextHolder.getRequestAttributes()can only be used in the Spring Web environment. In non-web environments (such as unit tests, background tasks, etc.), calling this method may return null. Therefore, you should be aware of your current environment when using this method.

In short, RequestContextHolder.getRequestAttributes()it provides a way to access the current request context in the non-Web layer code, which can conveniently obtain the information of the current request and perform business logic processing.