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 {

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(SentinelServerApplication.class);
    }

}

application.yaml

server:
  port: 8401

spring:
  application:
    name: cloudalibaba-sentinel-service
  cloud:
    nacos:
      discovery:
        server-addr: localhost:8848 #Nacos????????
    sentinel:
      transport:
        dashboard: localhost:8080 #??Sentinel dashboard??
        port: 8719

management:
  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>