当与A关联的资源B达到阀值后，就限流A自己

启动Sentinel8080 - java -jar sentinel-dashboard-1.7.0.jar

启动微服务8401

启动8401微服务后查看sentienl控制台
Sentinel采用的懒加载说明
执行一次访问即可
http://localhost:8401/testA

Postman模拟并发密集访问testB

FlowLimitController.java

package com.example.controller;import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;import static org.reflections.Reflections.log;@RestController
public class FlowLimitController {@GetMapping("/testA")public String testA(){return "------testA";}@GetMapping("/testB")public String testB(){log.info(Thread.currentThread().getName()+"\t"+"...testB");return "------testB";}}

SentinelServerApplication.java

package com.example;import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;@EnableDiscoveryClient
@SpringBootApplication
public class SentinelServerApplication {public static void main(String[] args) {SpringApplication.run(SentinelServerApplication.class, args);}}

ServletInitializer.java

package com.example;import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;public class ServletInitializer extends SpringBootServletInitializer {@Overrideprotected SpringApplicationBuilder configure(SpringApplicationBuilder application) {return application.sources(SentinelServerApplication.class);}}

application.yaml

server:port: 8401spring:application:name: cloudalibaba-sentinel-servicecloud:nacos:discovery:server-addr: localhost:8848 #Nacos????????sentinel:transport:dashboard: localhost:8080 #??Sentinel dashboard??port: 8719management:endpoints:web:exposure:include: '*'feign:sentinel:enabled: true # ??Sentinel?Feign???

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><parent><groupId>com.example</groupId><artifactId>springCloudAlibaba</artifactId><version>0.0.1-SNAPSHOT</version></parent><groupId>com.example</groupId><artifactId>sentinelServer</artifactId><version>0.0.1-SNAPSHOT</version><packaging>war</packaging><name>sentinelServer</name><description>sentinelServer</description><properties><java.version>1.8</java.version></properties><dependencies><!--SpringCloud ailibaba nacos --><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId></dependency><!--SpringCloud ailibaba sentinel --><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-sentinel</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-tomcat</artifactId><scope>provided</scope></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency></dependencies><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build></project>

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.7.6</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.example</groupId><artifactId>springCloudAlibaba</artifactId><version>0.0.1-SNAPSHOT</version><name>springCloudAlibaba</name><description>springCloudAlibaba</description><modules><module>sentinelServer</module></modules><packaging>pom</packaging><properties><java.version>1.8</java.version><spring-cloud.version>2021.0.4</spring-cloud.version><spring-cloud-alibaba.version>2021.0.4.0</spring-cloud-alibaba.version></properties><dependencyManagement><dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-dependencies</artifactId><version>${spring-cloud.version}</version><type>pom</type><scope>import</scope></dependency><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-alibaba-dependencies</artifactId><version>${spring-cloud-alibaba.version}</version><type>pom</type><scope>import</scope></dependency></dependencies></dependencyManagement><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build></project>