Block()/blockfirst()/blocklast() are blocking, which is not supported in thread reactor-http-nio-3

The methods block(), blockFirst(), and blockLast() are blocking methods that are not supported in the thread reactor-http-nio-3 framework. These methods are typically used to wait for a result from an asynchronous operation, but in a reactive programming model like thread reactor-http-nio-3, blocking operations are discouraged as they can lead to performance issues and thread starvation.

Instead of blocking, the thread reactor-http-nio-3 framework promotes the use of non-blocking operations and reactive streams. The reactive streams allow developers to build asynchronous, event-driven applications by using reactive programming concepts like publishers, subscribers, and operators.

Here’s a simple example to illustrate the difference between blocking and non-blocking operations in the context of thread reactor-http-nio-3:

    
      // Blocking operation
      String result = blockOperation(); // blocks current thread until result is available
      
      // Non-blocking operation
      Mono<String> resultMono = nonBlockOperation(); // returns a Mono (Publisher) immediately
      
      resultMono.subscribe(result -> {
        // Handle the result asynchronously
      });
    
  

In the example above, the method blockOperation() is a blocking operation that blocks the current thread until the result is available. This can lead to inefficient resource utilization and potential thread starvation in a reactive programming model.

On the other hand, the method nonBlockOperation() returns a Mono (Publisher) immediately without blocking the thread. The result is then asynchronously handled using the subscribe() method. This allows the thread reactor-http-nio-3 framework to efficiently manage threads and resources, making the application more scalable and resilient.