Java > Open Source Codes > org > mr > core > util > patterns > flow > ConfigurationLoader


1 package org.mr.core.util.patterns.flow;
2
3 import org.mr.core.util.exceptions.CreationException;
4 import org.w3c.dom.Document ;
5 import org.w3c.dom.Element ;
6 import org.w3c.dom.NodeList ;
7
8 import javax.xml.parsers.DocumentBuilder ;
9 import javax.xml.parsers.DocumentBuilderFactory ;
10 import java.util.HashMap ;
11 import java.util.Map ;
12
13 /*
14  * Copyright 2002 by
15  * <a HREF="http://www.coridan.com">Coridan</a>
16  * <a HREF="mailto: support@coridan.com ">support@coridan.com</a>
17  *
18  * The contents of this file are subject to the Mozilla Public License Version
19  * 1.1 (the "License"); you may not use this file except in compliance with the
20  * License. You may obtain a copy of the License at
21  * http://www.mozilla.org/MPL/
22  *
23  * Software distributed under the License is distributed on an "AS IS" basis,
24  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
25  * for the specific language governing rights and limitations under the
26  * License.
27  *
28  * The Original Code is "MantaRay" (TM).
29  *
30  * The Initial Developer of the Original Code is Coridan.
31  * Portions created by the Initial Developer are Copyright (C) 2006
32  * Coridan Inc. All Rights Reserved.
33  *
34  * Contributor(s): all the names of the contributors are added in the source
35  * code where applicable.
36  *
37  * Alternatively, the contents of this file may be used under the terms of the
38  * LGPL license (the "GNU LESSER GENERAL PUBLIC LICENSE"), in which case the
39  * provisions of LGPL are applicable instead of those above. If you wish to
40  * allow use of your version of this file only under the terms of the LGPL
41  * License and not to allow others to use your version of this file under
42  * the MPL, indicate your decision by deleting the provisions above and
43  * replace them with the notice and other provisions required by the LGPL.
44  * If you do not delete the provisions above, a recipient may use your version
45  * of this file under either the MPL or the GNU LESSER GENERAL PUBLIC LICENSE.
46  
47  *
48  * This library is free software; you can redistribute it and/or modify it
49  * under the terms of the MPL as stated above or under the terms of the GNU
50  * Lesser General Public License as published by the Free Software Foundation;
51  * either version 2.1 of the License, or any later version.
52  *
53  * This library is distributed in the hope that it will be useful, but WITHOUT
54  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
55  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
56  * License for more details.
57  */
58
59  /**
60  * User: Moti Tal
61  * Date: Mar 13, 2005
62  * Time: 12:57:06 PM
63  *
64  * This Class parses the configuration file and sets the FlowFramework.
65  */
66 public class ConfigurationLoader {
67
68     public final static String FLOW_STEP_CONDITION_TAG_NAME = "condition";
69     public final static String FLOW_STEP_CONDITIONS_TAG_NAME = "conditions";
70     public final static String FLOW_STEP_CONDITION_PARAM_ATTR_NAME = "variable";
71     public final static String FLOW_STEP_CONDITION_PARAM_VALUE_ATTR_NAME = "value";
72     public final static String FLOW_STEP_CONDITION_CLASS_ATTR_NAME = "class";
73
74     //configuration file path
75 String m_filePath = null;
76
77     //holds the frameworks after parsing
78 private static HashMap s_framworks = new HashMap ();
79
80     //use for overwrite tag name
81 //TODO SHOULD be replaced by common XML format using XSLT.
82 HashMap m_tagsAndAttributesNames = new HashMap ();
83
84     public ConfigurationLoader(String i_filePath, HashMap i_tagsAndAttributesNames) {
85         m_filePath = i_filePath;
86         if(i_tagsAndAttributesNames != null)
87             m_tagsAndAttributesNames.putAll(i_tagsAndAttributesNames);
88     }
89
90     /**
91      * Use as hook to get an empty FlowFramework
92       * @return a FlowFramework
93      */
94     protected FlowFramework generateEmptyFramework(){
95         return new DefaultFlowFramework();
96     }
97
98     /**
99      * Use as hook to get an empty Flow
100      * @return a Flow
101      */
102     protected Flow generateEmptyFlow(){
103         return new DefaultFlow();
104     }
105
106     protected Condition generateConditionSet(Element i_element) throws CreationException{
107         Conditional conditional = new Conditional();
108         conditional.configure(i_element);
109         NodeList conditions = i_element.getElementsByTagName(FLOW_STEP_CONDITION_TAG_NAME);
110         for(int j = 0; j < conditions.getLength() ; j++){
111             Condition condition = generateCondition((Element )conditions.item(j));
112             conditional.addCondition(condition);
113         }
114         conditions = i_element.getElementsByTagName(FLOW_STEP_CONDITIONS_TAG_NAME);
115         for(int j = 0; j < conditions.getLength() ; j++){
116             Condition condition = generateConditionSet((Element )conditions.item(j));
117             conditional.addCondition(condition);
118         }
119         return conditional;
120     }
121
122     protected Condition generateCondition(Element i_element) throws CreationException{
123         Condition condition = null;
124         try {
125
126             String className = i_element.getAttribute(FLOW_STEP_CONDITION_CLASS_ATTR_NAME);
127             if(className != null && className.length() > 0){
128                 condition = (Condition)loadClass(className).newInstance();
129             }else{
130                 condition = new StringCondition();
131             }
132             condition.configure(i_element);
133         } catch (Exception e) {
134             e.printStackTrace();
135             return null;
136         }
137         return condition;
138     }
139
140     /**
141      * Use as hook to overwrite configurable tag names.
142      * @param i_name the default name
143      * @return The default name or the applicative name if configured.
144      */
145     protected String getConfigurationName(String i_name){
146         String name = (String )m_tagsAndAttributesNames.get(i_name);
147         if(name == null)
148             return i_name;
149         return name;
150     }
151
152     /**
153      * a hook to set additional information to the Decleration
154      * @param i_declaration the current Decleration
155      */
156     protected void configureDeclaration(Declaration i_declaration){
157     }
158
159     /**
160      * Loads the FlowFramework
161      * @return a FlowFramework
162      * @throws Exception When parse configuration failed
163      */
164     public FlowFramework loadFramework() throws Exception {
165         //Check if the flow parsed already.
166 FlowFramework framework = (FlowFramework)s_framworks.get(m_filePath);
167         if(framework!= null)
168             return framework;
169
170         //call a hook to get an empty framework
171 framework = generateEmptyFramework();
172
173         DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
174         DocumentBuilder db = dbf.newDocumentBuilder();
175
176         // Read the entire document into memory
177 Document document = db.parse(m_filePath);
178
179         //add declarations
180 HashMap declarations = new HashMap ();
181         NodeList list = document.getElementsByTagName(getConfigurationName(Declaration.DECLARATION_TAG_NAME));
182         for (int i = 0 ; i < list.getLength() ; i++) {
183             Element dec = (Element )list.item(i);
184             //declaration
185 String className = dec.getAttribute(getConfigurationName(Declaration.DECLARATION_CLASS_ATTR_NAME));
186             String name = dec.getAttribute(getConfigurationName(Declaration.DECLARATION_NAME_ATTR_NAME));
187 // String entryPoint = panel.getAttribute(Declaration.DECLARATION_ENTRYPOINT_ATTR_NAME);
188 Declaration declaration = (Declaration)loadClass(className).newInstance();
189             declaration.configure(dec);
190 // declaration.setEntryPoint("true".equals(entryPoint));
191 configureDeclaration(declaration);
192             declarations.put(name, declaration);
193 // if(!panel.hasChildNodes())
194 // continue;
195 // //add input/output parameters for each panel
196 // NodeList directions = panel.getChildNodes();
197 // Map inputs = null, outputs = null;
198 // for (int j = 0 ; j < directions.getLength() ; j++) {
199 // Node node = directions.item(j);
200 // Map set = new HashMap();
201 // if(node.hasChildNodes()){
202 // NodeList params = panel.getChildNodes();
203 // for (int y = 0 ; y < params.getLength() ; y++) {
204 // Element input = (Element)params.item(y);
205 // set.put(input.getAttribute(Declaration.INPUT_AOUTPUT_PARAM_ATTR_NAME), null);
206 // }
207 // }
208 // if(XUIPanel.XUI_PANEL_INPUTS_TAG_NAME.equals(node.getNodeName())){
209 // inputs = new HashMap(set);
210 // }else if(Declaration.OUTPUTS_TAG_NAME.equals(node.getNodeName())){
211 // outputs = new HashMap(set);
212 // }
213 // declaration.configure(inputs,outputs);
214 // }
215 }
216
217         //add flows
218 list = document.getElementsByTagName(getConfigurationName(Flow.FLOW_TAG_NAME));
219         Flow flow = generateEmptyFlow();
220 // FlowCondition[] conditionArray = null;
221 if(list != null && list.getLength() == 1){
222             Element element = (Element )list.item(0);
223             if(element.hasChildNodes()){
224                 list = element.getElementsByTagName(getConfigurationName(Flow.FLOW_STEP_TAG_NAME));
225                  for (int i = 0 ; i < list.getLength() ; i++) {
226                     Element step = (Element )list.item(i);
227                     NodeList conditionsTag = step.getElementsByTagName(getConfigurationName(FLOW_STEP_CONDITIONS_TAG_NAME));
228                     Condition condition = null;
229                     if(conditionsTag != null && conditionsTag.getLength() == 1){
230                         Element cons = (Element )conditionsTag.item(0);
231 // NodeList conditions = cons.getElementsByTagName(getConfigurationName(FLOW_STEP_CONDITION_TAG_NAME));
232 // conditionArray = new FlowCondition[conditions.getLength()];
233 // for (int j = 0 ; j < conditions.getLength() ; j++) {
234 // Element condition = (Element)conditions.item(j);
235 // NamedNodeMap nodeMap = condition.getAttributes();
236 // Map map = new HashMap();
237 // for(int z = 0 ;z < nodeMap.getLength() ; z++){
238 // Node node = nodeMap.item(z);
239 // map.put(node.getNodeName(),node.getNodeValue());
240 // }
241 // conditionArray[j] = generateCondition(condition);
242 // }
243 condition = generateConditionSet(cons);
244                     }
245
246                     flow.addStep(step.getAttribute(getConfigurationName(Flow.FLOW_STEP_ID_ATTR_NAME)),
247                                  (Declaration)declarations.get(step.getAttribute(getConfigurationName(Flow.FLOW_STEP_FROM_ATTR_NAME))),
248                                  (Declaration)declarations.get(step.getAttribute(getConfigurationName(Flow.FLOW_STEP_TO_ATTR_NAME))),
249                                  condition);
250                  }
251             }
252         }
253         framework.setFlow(flow);
254         s_framworks.put(m_filePath,framework);
255         return framework;
256     }
257
258     /**
259      * A default condition.
260      * This condition checks 2 strings to met the condition.
261      */
262     private class StringCondition implements Condition{
263         String m_name;
264         String m_value;
265
266         public void configure(Element i_object) throws CreationException {
267             m_name = i_object.getAttribute(getConfigurationName(FLOW_STEP_CONDITION_PARAM_ATTR_NAME));
268             m_value = i_object.getAttribute(getConfigurationName(FLOW_STEP_CONDITION_PARAM_VALUE_ATTR_NAME));
269         }
270
271         public boolean metCondition(Object i_param) {
272             String value = (String )((Map )i_param).get(m_name);
273             return m_value.equals(value);
274         }
275     }
276
277     public static void main(String [] args) {
278         try {
279             HashMap hashMap = new HashMap ();
280             hashMap.put(Declaration.DECLARATION_TAG_NAME, "plugin");
281             hashMap.put(Flow.FLOW_TAG_NAME, "flow");
282             ConfigurationLoader defaultLoader = new ConfigurationLoader("conf.xml", hashMap);
283             FlowFramework framwork = defaultLoader.loadFramework();
284 // framwork.execute(new ActivationDataObject());
285 } catch (Exception e) {
286             e.printStackTrace();
287         }
288     }
289
290     public Class loadClass(String i_name)throws Exception {
291         try {
292             return Thread.currentThread().getContextClassLoader().loadClass(i_name);
293         } catch (NullPointerException e) { //native call patch
294 return Class.forName(i_name);
295         }
296     }
297 }
298

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