小编lin*_*bon的帖子

通过使用 Blockhound io.projectreactor.tools blockhound-junit-platform我发现 UUID.randomUUID 是一个阻塞调用，这对我们来说是一个问题，因为我们使用的是 Spring Boot Webflux 版本 2.2.2.RELEASE

有没有其他方法可以以非阻塞方式获取随机 uuid，或者是否有任何其他 Java 库推荐用于非阻塞生成随机字符串。

来自blockhound的堆栈跟踪：

java.lang.Error: Blocking call! java.io.FileInputStream#readBytes
at reactor.blockhound.BlockHound$Builder.lambda$new$0(BlockHound.java:196) ~[blockhound-1.0.1.RELEASE.jar:na]
Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: 
Error has been observed at the following site(s):
|_ checkpoint ? org.springframework.boot.actuate.metrics.web.reactive.server.MetricsWebFilter [DefaultWebFilterChain][ExceptionHandlingWebHandler]
Stack trace:
    at reactor.blockhound.BlockHound$Builder.lambda$new$0(BlockHound.java:196) ~[blockhound-1.0.1.RELEASE.jar:na]
    at reactor.blockhound.BlockHound$Builder.lambda$install$6(BlockHound.java:318) ~[blockhound-1.0.1.RELEASE.jar:na]
    at reactor.blockhound.BlockHoundRuntime.checkBlocking(BlockHoundRuntime.java:46) ~[na:na]
    at java.base/java.io.FileInputStream.readBytes(FileInputStream.java) ~[na:na]
    at java.base/java.io.FileInputStream.read(FileInputStream.java:279) ~[na:na]
    at java.base/java.io.FilterInputStream.read(FilterInputStream.java:133) ~[na:na]
    at java.base/sun.security.provider.NativePRNG$RandomIO.readFully(NativePRNG.java:424) ~[na:na]
    at java.base/sun.security.provider.NativePRNG$RandomIO.ensureBufferValid(NativePRNG.java:526) ~[na:na]
    at java.base/sun.security.provider.NativePRNG$RandomIO.implNextBytes(NativePRNG.java:545) ~[na:na]
    at java.base/sun.security.provider.NativePRNG.engineNextBytes(NativePRNG.java:220) ~[na:na]
    at java.base/java.security.SecureRandom.nextBytes(SecureRandom.java:741) ~[na:na]
    at java.base/java.util.UUID.randomUUID(UUID.java:150) ~[na:na]

我正在运行一个带有 rest api 的无状态 spring-boot 应用程序，并希望按照https://www.baeldung.com/spring-security-session 的描述禁用 WebSessions 的创建

我创建了自己的 WebSessionManager，它不存储会话。

   @Bean
   public WebSessionManager webSessionManager() {
       return new WebSessionManager() {
           @Override
           @NonNull
           public Mono<WebSession> getSession(@NonNull final ServerWebExchange exchange) {
               return Mono.just(new WebSession() {

                   @Override
                   @NonNull
                   public String getId() {
                       return "";
                   }

                   @Override
                   @NonNull
                   public Map<String, Object> getAttributes() {
                       return new HashMap<>();
                   }

                   @Override
                   public void start() {
                   }

                   @Override
                   public boolean isStarted() {
                       return true;
                   }

                   @Override
                   @NonNull
                   public Mono<Void> changeSessionId() {
                       return Mono.empty();
                   }

                   @Override
                   @NonNull …