tomcat enable virtual thread

config.java

import org.apache.catalina.connector.Connector;
import org.apache.coyote.ProtocolHandler;
import org.apache.coyote.http11.Http11NioProtocol;
import org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;
import java.util.logging.Logger;

@Configuration
public class TomcatConfig {

    private static final Logger LOGGER = Logger.getLogger(TomcatConfig.class.getName());

    @Bean
    public TomcatServletWebServerFactory tomcatFactory() {
        return new TomcatServletWebServerFactory() {
            @Override
            protected void customizeConnector(Connector connector) {
                ProtocolHandler protocolHandler = connector.getProtocolHandler();
                if (protocolHandler instanceof Http11NioProtocol http11NioProtocol) {
                    // Use Virtual Threads
                    Executor virtualThreadExecutor = Executors.newVirtualThreadPerTaskExecutor();
                    http11NioProtocol.setExecutor(virtualThreadExecutor);

                    // Log confirmation
                    LOGGER.info("Tomcat is using Virtual Threads for request handling!");
                }
            }
        };
    }
}

TestVirtualThread.java

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/test")
public class TestController {

    @GetMapping("/thread")
    public String checkThread() {
        String threadName = Thread.currentThread().toString();
        System.out.println("Handling request in: " + threadName);
        return "Current Thread: " + threadName;
    }
}