// $Header: /home/cvs/jakarta-jmeter/src/protocol/http/org/apache/jmeter/protocol/http/util/accesslog/Generator.java,v 1.4 2004/02/12 00:29:48 sebb Exp $
/*
 * Copyright 2003-2004 The Apache Software Foundation.
 *
 * 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 org.apache.jmeter.protocol.http.util.accesslog;


/**
 * Description:

 * 

 * Generator is a base interface that defines
 * the minimum methods needed to implement a
 * concrete generator. The reason for creating
 * this interface is eventually JMeter could
 * use the logs directly rather than pre-
 * process the logs into a JMeter .jmx file.
 * In situations where a test plan simulates
 * load from production logs, it is more
 * efficient for JMeter to use the logs
 * directly.

 * From first hand experience, loading a test
 * plan with 10K or more Requests requires a
 * lot of memory. It's important to keep in
 * mind this type of testing is closer to
 * functional and regression testing than the
 * typical stress tests. Typically, this kind
 * of testing is most useful for search sites
 * that get a large number of requests per
 * day, but the request parameters vary
 * dramatically. E-commerce sites typically
 * have limited inventory, therefore it is
 * better to design test plans that use data
 * from the database.
 * 

 * @author	Peter Lin
 * @version $Revision: 1.4 $ last updated on $Date: 2004/02/12 00:29:48 $
 * Created on:	Jun 23, 2003

 */

public interface Generator {

	/**
	 * close the generator
	 */
	public void close();

	/**
	 * The host is the name of the server.
	 * @param host
	 */	
	public void setHost(String host);

	/**
	 * This is the label for the request,
	 * which is used in the logs and
	 * results.
	 * @param label
	 */
	public void setLabel(String label);

	/**
	 * The method is the HTTP request
	 * method. It's normally POST or GET.
	 * @param post_get
	 */	
	public void setMethod(String post_get);

	/**
	 * Set the request parameters
	 * @param params
	 */	
	public void setParams(NVPair[] params);

	/**
	 * The path is the web page you want
	 * to test.
	 * @param path
	 */
	public void setPath(String path);

	/**
	 * The default port for HTTP is 80,
	 * but not all servers run on that
	 * port.
	 * @param port - port number
	 */	
	public void setPort(int port);

	/**
	 * Set the querystring for the request
	 * if the method is GET.
	 * @param querystring
	 */	
	public void setQueryString(String querystring);

	/**
	 * The source logs is the location
	 * where the access log resides.
	 * @param sourcefile
	 */
	public void setSourceLogs(String sourcefile);

	/**
	 * The target can be either a java.io.File
	 * or a Sampler. We make it generic, so
	 * that later on we can use these classes
	 * directly from a HTTPSampler.
	 * @param target
	 */	
	public void setTarget(Object target);

	/**
	 * The method is responsible for calling
	 * the necessary methods to generate a
	 * valid request. If the generator is
	 * used to pre-process access logs, the
	 * method wouldn't return anything. If
	 * the generator is used by a control
	 * element, it should return the correct
	 * Sampler class with the required
	 * fields set.
	 */	
	public Object generateRequest();
	
	/**
	 * If the generator is converting the logs
	 * to a .jmx file, save should be called.
	 */
	public void save();
	
	/**
	 * The purpose of the reset is so Samplers
	 * can explicitly call reset to create a 
	 * new instance of HTTPSampler.
	 *
	 */
	public void reset();
}