flow4jruntimewebutils.java

一个java写的business process management系统

/*
 * Copyright (c) 2003-2004, Alexander Greif
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the Flow4J-Eclipse project nor the names of its
 *       contributors may be used to endorse or promote products derived from
 *       this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

package net.orthanc.flow4j.runtime.web;

import java.util.Enumeration;
import java.util.Iterator;
import java.util.Map;
import java.util.StringTokenizer;

import javax.servlet.GenericServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import net.orthanc.flow4j.runtime.Flow4JRuntimeException;
import net.orthanc.flow4j.runtime.FlowDictionary;
import net.orthanc.flow4j.runtime.FlowManager;
import net.orthanc.flow4j.runtime.IFlowRepository;

/**
 * Class Flow4JRuntimeWebUtils TODO
 * @author agreif
 * 
 */
public class Flow4JRuntimeWebUtils {

	private static String servletPath;
	
	
	/**
	 * 
	 * TODO
	 * @param path
	 */
	static public void setServletPath(String path) {
		servletPath = path;
	}

	/**
	 * Returns the servlet path that was supported by the init parameters.
	 * It is needed by the flow4j:link tag.
	 * @return
	 */
	public static String getServletPath() {
		return servletPath;
	}





	/**	Returns the flow's and the startnode's name in the form
	 * <code>flowname-startflowletname</code>
	 */
	static public String getFlowStartDesc(HttpServletRequest req)
		throws Flow4JRuntimeException
	{
		String pathInfo = req.getPathInfo();
		if (pathInfo == null)
			throw new Flow4JRuntimeException("no flow and entry specified (pathInfo: null)");


		StringTokenizer tokens = new StringTokenizer(pathInfo,"/");
		if (tokens.hasMoreTokens())
			return tokens.nextToken();

		throw new Flow4JRuntimeException("no flow and entry specified (pathInfo: " + pathInfo);
	}




	/**
	 * Transfers request parameters into the dictionary:
	 * the request itself, the session if exists, the response and the servlet
	 * to the dictionary
	 */
	static public void transferParameters(
		HttpServletRequest req,
		HttpServletResponse res,
		GenericServlet servlet,
		FlowDictionary dictionary) {
		for (Enumeration enum = req.getParameterNames();
			enum.hasMoreElements();
			) {
			String name = (String) enum.nextElement();
			String[] value = req.getParameterValues(name);

			if (value.length == 1)
				dictionary.put(name, value[0]);
			else
				dictionary.put(name, value);
		}

		dictionary.put(Flow4JRuntimeWebConsts.DICT_KEY_SERVLET_REQUEST, req);
		dictionary.put(
			Flow4JRuntimeWebConsts.DICT_KEY_HTTP_SESSION,
			req.getSession(false));
		dictionary.put(Flow4JRuntimeWebConsts.DICT_KEY_SERVLET_RESPONSE, res);
		dictionary.put(Flow4JRuntimeWebConsts.DICT_KEY_SERVLET, servlet);
	}

	/**
	 * Transfers dictionary parameters as attributes to the request.
	 */
	static public void transferParameters(
		FlowDictionary dictionary,
		HttpServletRequest req) {
		for (Iterator iter = dictionary.entrySet().iterator();
			iter.hasNext();
			) {
			Map.Entry entry = (Map.Entry) iter.next();
			req.setAttribute(entry.getKey().toString(), entry.getValue());
		}
	}



	/**
	 * Registers the flows and sets some init params.
	 * The flow registry's classname is supported by the servlet init parameter
	 * <code>flow-repository-class</code>. If a flow registry is supported, then 
	 * it is used to register the flows at the flowManager.
	 */
	static public void registerFlowsFromRepository(String servletPath, String flowRepositoryClassName) throws Exception {
		servletPath =
			servletPath == null ? Flow4JRuntimeWebConsts.DEFAULT_SERVLET_PATH : servletPath;
		Flow4JRuntimeWebUtils.setServletPath(servletPath);
		//	register flows
		if (flowRepositoryClassName != null) {
			IFlowRepository flowRepository =
				(IFlowRepository) Class
					.forName(flowRepositoryClassName)
					.newInstance();
			FlowManager.registerFlows(flowRepository);
		}

	}
}