Java tutorial
/** * Licensed to DigitalPebble Ltd under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * DigitalPebble licenses this file to You 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 com.digitalpebble.stormcrawler.protocol.selenium; import java.util.concurrent.LinkedBlockingQueue; import org.apache.storm.Config; import org.openqa.selenium.remote.RemoteWebDriver; import org.slf4j.LoggerFactory; import com.digitalpebble.stormcrawler.Metadata; import com.digitalpebble.stormcrawler.protocol.AbstractHttpProtocol; import com.digitalpebble.stormcrawler.protocol.ProtocolResponse; public abstract class SeleniumProtocol extends AbstractHttpProtocol { protected static final org.slf4j.Logger LOG = LoggerFactory.getLogger(SeleniumProtocol.class); protected LinkedBlockingQueue<RemoteWebDriver> drivers; private NavigationFilters filters; @Override public void configure(Config conf) { super.configure(conf); drivers = new LinkedBlockingQueue<>(); filters = NavigationFilters.fromConf(conf); } public ProtocolResponse getProtocolOutput(String url, Metadata metadata) throws Exception { // TODO check that the driver is not null RemoteWebDriver driver = getDriver(); try { // This will block for the page load and any // associated AJAX requests driver.get(url); // call the filters ProtocolResponse response = filters.filter(driver, metadata); if (response == null) { // if no filters got triggered byte[] content = driver.getPageSource().getBytes(); response = new ProtocolResponse(content, 200, metadata); } return response; } finally { // finished with this driver - return it to the queue drivers.put(driver); } } /** Returns the first available driver **/ private final RemoteWebDriver getDriver() { RemoteWebDriver d = null; try { d = drivers.take(); } catch (InterruptedException e) { } return d; } }