SimpleUndertowExtension.java

package org.jboss.as.test.integration.web.extension;

import javax.servlet.ServletContext;

import io.undertow.io.IoCallback;
import io.undertow.server.HandlerWrapper;
import io.undertow.server.HttpHandler;
import io.undertow.server.HttpServerExchange;
import io.undertow.servlet.ServletExtension;
import io.undertow.servlet.api.DeploymentInfo;

/**
 * @author Stuart Douglas
 */
public class SimpleUndertowExtension implements ServletExtension {

    static final String THIS_IS_NOT_A_SERVLET = "This is not a servlet";

    @Override
    public void handleDeployment(final DeploymentInfo deploymentInfo, final ServletContext servletContext) {
        deploymentInfo.addInitialHandlerChainWrapper(new HandlerWrapper() {
            @Override
            public HttpHandler wrap(final HttpHandler handler) {
                return new HttpHandler() {
                    @Override
                    public void handleRequest(final HttpServerExchange exchange) throws Exception {
                        if(Thread.currentThread() != exchange.getIoThread()) {
                            exchange.setStatusCode(500);
                            exchange.getResponseSender().send("Response was dispatched, not running in IO thread", IoCallback.END_EXCHANGE);
                        }
                        exchange.getResponseSender().send(THIS_IS_NOT_A_SERVLET, IoCallback.END_EXCHANGE);
                    }
                };
            }
        });
    }
}