/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2014 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package io.undertow.server.handlers;

import java.util.Collections;
import java.util.Map;
import java.util.Set;

import io.undertow.server.HandlerWrapper;
import io.undertow.server.HttpHandler;
import io.undertow.server.HttpServerExchange;
import io.undertow.server.handlers.builder.HandlerBuilder;

A HttpHandler that initiates a blocking request. If the thread is currently running in the io thread it will be dispatched.
Author:Stuart Douglas, David M. Lloyd
/** * A {@link HttpHandler} that initiates a blocking request. If the thread is currently running * in the io thread it will be dispatched. * * @author Stuart Douglas * @author <a href="mailto:david.lloyd@redhat.com">David M. Lloyd</a> */
public final class BlockingHandler implements HttpHandler { private volatile HttpHandler handler; public BlockingHandler(final HttpHandler handler) { this.handler = handler; } public BlockingHandler() { this(null); } @Override public void handleRequest(final HttpServerExchange exchange) throws Exception { exchange.startBlocking(); if (exchange.isInIoThread()) { exchange.dispatch(handler); } else { handler.handleRequest(exchange); } } public HttpHandler getHandler() { return handler; } public BlockingHandler setRootHandler(final HttpHandler rootHandler) { this.handler = rootHandler; return this; } @Override public String toString() { return "blocking()"; } public static class Builder implements HandlerBuilder { @Override public String name() { return "blocking"; } @Override public Map<String, Class<?>> parameters() { return Collections.emptyMap(); } @Override public Set<String> requiredParameters() { return Collections.emptySet(); } @Override public String defaultParameter() { return null; } @Override public HandlerWrapper build(Map<String, Object> config) { return new Wrapper(); } } private static class Wrapper implements HandlerWrapper { @Override public HttpHandler wrap(HttpHandler handler) { return new BlockingHandler(handler); } } }