CompletionLatchHandler.java

/*
 * 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.util;

import io.undertow.server.ExchangeCompletionListener;
import io.undertow.server.HttpHandler;
import io.undertow.server.HttpServerExchange;

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

/**
 * @author Stuart Douglas
 */
public class CompletionLatchHandler implements HttpHandler {

    private final HttpHandler next;
    private volatile CountDownLatch latch;

    public CompletionLatchHandler(HttpHandler next) {
        this.next = next;
        latch = new CountDownLatch(1);
    }

    public CompletionLatchHandler(int size, HttpHandler next) {
        this.next = next;
        latch = new CountDownLatch(size);
    }
    public void await() {
        try {
            latch.await(10, TimeUnit.SECONDS);
        } catch (InterruptedException e) {
            throw new RuntimeException(e);
        }
    }

    public void reset() {
        this.latch = new CountDownLatch(1);
    }

    public void reset(int size) {
        this.latch = new CountDownLatch(size);
    }
    @Override
    public void handleRequest(HttpServerExchange exchange) throws Exception {
        exchange.addExchangeCompleteListener(new ExchangeCompletionListener() {
            @Override
            public void exchangeEvent(HttpServerExchange exchange, NextListener nextListener) {
                latch.countDown();
                nextListener.proceed();
            }
        });
        next.handleRequest(exchange);
    }
}