1. pom中需要先增加如下的内容

<dependency><groupId>io.micrometer</groupId><artifactId>context-propagation</artifactId><version>1.1.2</version>
</dependency>

2. 注意，要看idea是否将context-propagation引入了。我的idea就是不知道为什么，虽然pom中添加了这个maven，mvn clean install 也通过了，但是在idea中的三方库就是没有。我进行了手动引入

3. 编写类继承ThreadLocalAccessor<String>。这个编写类的内容在官方文档中没有，坑人。因此按照官方文档，是不可能得到预期结果的

import io.micrometer.context.ThreadLocalAccessor;
import io.micrometer.context.ContextRegistry;public class CustomThreadLocalAccessor implements ThreadLocalAccessor<String> {public static final ThreadLocal<String> TL = new ThreadLocal<>();@Overridepublic Object key() {return "TLKEY";}@Overridepublic String getValue() {return TL.get();}@Overridepublic void setValue(String value) {TL.set(value);}@Overridepublic void reset() {TL.remove();}
}

4. 使用

   public static void main(String[] args) throws ClassNotFoundException {// 注册 ThreadLocalAccessorContextRegistry.getInstance().registerThreadLocalAccessor(new CustomThreadLocalAccessor());// 启用自动 Context 传播Hooks.enableAutomaticContextPropagation();// 假设 TL 是注册的 ThreadLocalCustomThreadLocalAccessor.TL.set("HELLO");String TLKEY = "TLKEY";String x =Mono.just(1).flatMap(v -> Mono.deferContextual(ctx->Mono.just(Thread.currentThread().getName()+"-"+"delayed ctx[" + TLKEY + "]=" + ctx.getOrDefault(TLKEY, "not found") + ", " +"TL=" + CustomThreadLocalAccessor.TL.get()))).contextWrite(ctx -> ctx.put(TLKEY, "HELLO")).flatMap(v -> Mono.deferContextual(ctx->Mono.just(Thread.currentThread().getName()+"-"+"delayed ctx[" + TLKEY + "]=" + ctx.getOrDefault(TLKEY, "not found") + ", " +"TL=" + CustomThreadLocalAccessor.TL.get()))).contextWrite(ctx -> Context.empty()).subscribeOn(Schedulers.boundedElastic()).block();System.out.println(x);}