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1
5 package com.opensymphony.workflow.loader;
6
7 import com.opensymphony.workflow.FactoryException;
8 import com.opensymphony.workflow.InvalidWorkflowDescriptorException;
9
10 import org.w3c.dom.*;
11
12 import java.io.*;
13
14 import java.net.URL  ;
15
16 import java.util.*;
17
18 import javax.xml.parsers.*;
19
20
21
26 public class XMLWorkflowFactory extends AbstractWorkflowFactory {
27
29 protected Map workflows;
30 protected boolean reload;
31
32
34 public WorkflowDescriptor getWorkflow(String name) throws FactoryException {
35 WorkflowConfig c = (WorkflowConfig) workflows.get(name);
36
37 if (c == null) {
38 throw new FactoryException("Unknown workflow name \"" + name + "\"");
39 }
40
41 if (c.descriptor != null) {
42 if (reload) {
43 File file = new File(c.url.getFile());
44
45 if (file.exists() && (file.lastModified() > c.lastModified)) {
46 c.lastModified = file.lastModified();
47 loadWorkflow(c);
48 }
49 }
50 } else {
51 loadWorkflow(c);
52 }
53
54 return c.descriptor;
55 }
56
57 public String [] getWorkflowNames() {
58 int i = 0;
59 String [] res = new String [workflows.keySet().size()];
60 Iterator it = workflows.keySet().iterator();
61
62 while (it.hasNext()) {
63 res[i++] = (String ) it.next();
64 }
65
66 return res;
67 }
68
69 public void initDone() throws FactoryException {
70 reload = getProperties().getProperty("reload", "false").equals("true");
71
72 ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
73 InputStream is = null;
74 String name = getProperties().getProperty("resource", "workflows.xml");
75
76 if ((name != null) && (name.indexOf(":/") > -1)) {
77 try {
78 is = new URL (name).openStream();
79 } catch (Exception e) {
80 }
81 }
82
83 if (is == null) {
84 try {
85 is = classLoader.getResourceAsStream(name);
86 } catch (Exception e) {
87 }
88 }
89
90 if (is == null) {
91 try {
92 is = classLoader.getResourceAsStream("/" + name);
93 } catch (Exception e) {
94 }
95 }
96
97 if (is == null) {
98 try {
99 is = classLoader.getResourceAsStream("META-INF/" + name);
100 } catch (Exception e) {
101 }
102 }
103
104 if (is == null) {
105 try {
106 is = classLoader.getResourceAsStream("/META-INF/" + name);
107 } catch (Exception e) {
108 }
109 }
110
111 try {
112 DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
113 dbf.setNamespaceAware(true);
114
115 DocumentBuilder db = null;
116
117 try {
118 db = dbf.newDocumentBuilder();
119 } catch (ParserConfigurationException e) {
120 throw new FactoryException("Error creating document builder", e);
121 }
122
123 Document doc = db.parse(is);
124
125 Element root = (Element) doc.getElementsByTagName("workflows").item(0);
126 workflows = new HashMap();
127
128 List list = XMLUtil.getChildElements(root, "workflow");
129
130 for (int i = 0; i < list.size(); i++) {
131 Element e = (Element) list.get(i);
132 WorkflowConfig config = new WorkflowConfig(e.getAttribute("type"), e.getAttribute("location"));
133 workflows.put(e.getAttribute("name"), config);
134 }
135 } catch (Exception e) {
136 throw new InvalidWorkflowDescriptorException("Error in workflow config", e);
137 }
138 }
139
140 public boolean removeWorkflow(String name) throws FactoryException {
141 throw new FactoryException("remove workflow not supported");
142
143 }
151
152 public boolean saveWorkflow(String name, WorkflowDescriptor descriptor, boolean replace) throws FactoryException {
153 WorkflowConfig c = (WorkflowConfig) workflows.get(name);
154
155 if ((c != null) && !replace) {
156 return false;
157 }
158
159 if (c == null) {
160 throw new UnsupportedOperationException ("Saving of new workflow is not currently supported");
161 }
162
163 Writer out;
164 descriptor.validate();
165
166 try {
167 out = new OutputStreamWriter(new FileOutputStream(c.url.getFile() + ".new"), "utf-8");
168 } catch (FileNotFoundException ex) {
169 throw new FactoryException("Could not create new file to save workflow " + c.url.getFile());
170 } catch (UnsupportedEncodingException ex) {
171 throw new FactoryException("utf-8 encoding not supported, contact your JVM vendor!");
172 }
173
174 writeXML(descriptor, out);
175
176 File original = new File(c.url.getFile());
179 File backup = new File(c.url.getFile() + ".bak");
180 File updated = new File(c.url.getFile() + ".new");
181 boolean isOK = !original.exists() || original.renameTo(backup);
182
183 if (!isOK) {
184 throw new FactoryException("Unable to backup original workflow file " + original + " to " + backup + ", aborting save");
185 }
186
187 isOK = updated.renameTo(original);
188
189 if (!isOK) {
190 throw new FactoryException("Unable to rename new workflow file " + updated + " to " + original + ", aborting save");
191 }
192
193 backup.delete();
194
195 return true;
196 }
197
198 protected void save() {
199 }
200
201 protected void writeXML(WorkflowDescriptor descriptor, Writer out) {
202 PrintWriter writer = new PrintWriter(new BufferedWriter(out));
203 writer.println(WorkflowDescriptor.XML_HEADER);
204 writer.println(WorkflowDescriptor.DOCTYPE_DECL);
205 descriptor.writeXML(writer, 0);
206 writer.flush();
207 writer.close();
208 }
209
210 private void loadWorkflow(WorkflowConfig c) throws FactoryException {
211 try {
212 c.descriptor = WorkflowLoader.load(c.url);
213 } catch (Exception e) {
214 throw new FactoryException("Error in workflow descriptor: " + c.url, e);
215 }
216 }
217
218
220 class WorkflowConfig {
221 String location;
222 String type;
223 URL url;
224 WorkflowDescriptor descriptor;
225 long lastModified;
226
227 public WorkflowConfig(String type, String location) {
228 if ("URL".equals(type)) {
229 try {
230 url = new URL (location);
231
232 File file = new File(url.getFile());
233
234 if (file.exists()) {
235 lastModified = file.lastModified();
236 }
237 } catch (Exception ex) {
238 }
239 } else if ("file".equals(type)) {
240 try {
241 File file = new File(location);
242 url = file.toURL();
243 lastModified = file.lastModified();
244 } catch (Exception ex) {
245 }
246 } else {
247 url = Thread.currentThread().getContextClassLoader().getResource(location);
248 }
249
250 this.type = type;
251 this.location = location;
252 }
253 }
254 }
255 |
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