workloadmanager.java

VHDL制作的ann的code

/*
 * Encog Neural Network and Bot Library for Java v1.x
 * http://www.heatonresearch.com/encog/
 * http://code.google.com/p/encog-java/
 * 
 * Copyright 2008, Heaton Research Inc., and individual contributors.
 * See the copyright.txt in the distribution for a full listing of 
 * individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.encog.bot.spider.workload;

import java.net.URL;
import java.util.concurrent.TimeUnit;

import org.encog.bot.spider.Spider;

/**
 * WorkloadManager: This interface defines a workload manager. A workload
 * manager handles the lists of URLs that have been processed, resulted in an
 * error, and are waiting to be processed.
 */
public interface WorkloadManager {
	/**
	 * Add the specified URL to the workload.
	 * 
	 * @param url
	 *            The URL to be added.
	 * @param source
	 *            The page that contains this URL.
	 * @param depth
	 *            The depth of this URL.
	 * @return True if the URL was added, false otherwise.
	 * @throws WorkloadException
	 */
	boolean add(URL url, URL source, int depth);

	/**
	 * Clear the workload.
	 */
	void clear();

	/**
	 * Determine if the workload contains the specified URL.
	 * 
	 * @param url
	 *            The URL to search for.
	 * @return True if the specified URL is contained.
	 * @throws WorkloadException
	 */
	boolean contains(URL url);

	/**
	 * Convert the specified String to a URL. If the string is too long or has
	 * other issues, throw a WorkloadException.
	 * 
	 * @param url
	 *            A String to convert into a URL.
	 * @return The URL.
	 */
	URL convertURL(String url);

	/**
	 * Get the current host.
	 * 
	 * @return The current host.
	 */
	String getCurrentHost();

	/**
	 * Get the depth of the specified URL.
	 * 
	 * @param url
	 *            The URL to get the depth of.
	 * @return The depth of the specified URL.
	 */
	int getDepth(URL url);

	/**
	 * Get the source page that contains the specified URL.
	 * 
	 * @param url
	 *            The URL to seek the source for.
	 * @return The source of the specified URL.
	 */
	URL getSource(URL url);

	/**
	 * Get a new URL to work on. Wait if there are no URL's currently available.
	 * Return null if done with the current host. The URL being returned will be
	 * marked as in progress.
	 * 
	 * @return The next URL to work on,
	 */
	URL getWork();

	/**
	 * Setup this workload manager for the specified spider.
	 * 
	 * @param spider
	 *            The spider using this workload manager.
	 */
	void init(Spider spider);

	/**
	 * Mark the specified URL as error.
	 * 
	 * @param url
	 *            The URL that had an error.
	 */
	void markError(URL url);

	/**
	 * Mark the specified URL as successfully processed.
	 * 
	 * @param url
	 *            The URL to mark as processed.
	 */
	void markProcessed(URL url);

	/**
	 * Move on to process the next host. This should only be called after
	 * getWork returns null.
	 * 
	 * @return The name of the next host.
	 */
	String nextHost();

	/**
	 * Setup the workload so that it can be resumed from where the last spider
	 * left the workload.
	 */
	void resume();

	/**
	 * If there is currently no work available, then wait until a new URL has
	 * been added to the workload.
	 * 
	 * @param time
	 *            The amount of time to wait.
	 * @param length
	 *            What time unit is being used.
	 */
	void waitForWork(int time, TimeUnit length);

	/**
	 * Return true if there are no more workload units.
	 * 
	 * @return Returns true if there are no more workload units.
	 */
	boolean workloadEmpty();

}