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1
5 package com.opensymphony.workflow.loader;
6
7 import com.opensymphony.module.propertyset.PropertySet;
8
9 import com.opensymphony.workflow.FactoryException;
10 import com.opensymphony.workflow.FunctionProvider;
11
12 import org.apache.commons.logging.Log;
13 import org.apache.commons.logging.LogFactory;
14
15 import org.xml.sax.SAXException  ;
16
17 import java.io.*;
18
19 import java.sql.*;
20
21 import java.util.HashMap ;
22 import java.util.Iterator ;
23 import java.util.Map ;
24
25 import javax.naming.InitialContext ;
26 import javax.naming.NamingException ;
27
28 import javax.sql.DataSource ;
29
30
31
47 public class JDBCWorkflowFactory extends XMLWorkflowFactory implements FunctionProvider {
48
50 private static final Log log = LogFactory.getLog(JDBCWorkflowFactory.class);
51 final static String wfTable = "OS_WORKFLOWDEFS";
52 final static String wfName = "WF_NAME";
53 final static String wfDefinition = "WF_DEFINITION";
54
55
57 protected DataSource ds;
58 protected Map workflows;
59 protected boolean reload;
60
61
63 public WorkflowDescriptor getWorkflow(String name) throws FactoryException {
64 WfConfig c = (WfConfig) workflows.get(name);
65
66 if (c == null) {
67 throw new RuntimeException ("Unknown workflow name \"" + name + "\"");
68 }
69
70 if (log.isDebugEnabled()) {
71 log.debug("getWorkflow " + name + " descriptor=" + c.descriptor);
72 }
73
74 if (c.descriptor != null) {
75 if (reload) {
76 try {
78 c.descriptor = load(c.wfName);
79 } catch (FactoryException e) {
80 throw e;
81 } catch (Exception e) {
82 throw new FactoryException("Error reloading workflow", e);
83 }
84 }
85 } else {
86 if (log.isDebugEnabled()) {
87 try {
88 c.descriptor = load(c.wfName);
89 } catch (FactoryException e) {
90 throw e;
91 } catch (Exception e) {
92 throw new FactoryException("Error loading workflow", e);
93 }
94 }
95 }
96
97 return c.descriptor;
98 }
99
100 public String [] getWorkflowNames() {
101 int i = 0;
102 String [] res = new String [workflows.keySet().size()];
103 Iterator it = workflows.keySet().iterator();
104
105 while (it.hasNext()) {
106 res[i++] = (String ) it.next();
107 }
108
109 return res;
110 }
111
112 public void execute(Map transientVars, Map args, PropertySet ps) {
113 String name = (String ) args.get("name");
114 WorkflowDescriptor wfds = (WorkflowDescriptor) transientVars.get("descriptor");
115
116 try {
117 saveWorkflow(name, wfds, false);
118 } catch (Exception e) {
119 }
120 }
121
122 public void initDone() throws FactoryException {
123 Connection conn = null;
124
125 try {
126 init();
127 reload = getProperties().getProperty("reload", "false").equalsIgnoreCase("true");
128
129 conn = ds.getConnection();
130
131 PreparedStatement ps = conn.prepareStatement("SELECT " + wfName + "," + wfDefinition + " FROM " + wfTable);
132 ResultSet rs = ps.executeQuery();
133
134 while (rs.next()) {
135 String name = rs.getString(1);
136 WfConfig config = new WfConfig(name);
137 workflows.put(rs.getString(1), config);
138 }
139
140 rs.close();
141 ps.close();
142 } catch (Exception e) {
143 throw new FactoryException("Could not read workflow names from datasource", e);
144 } finally {
145 try {
146 conn.close();
147 } catch (Exception ex) {
148 }
149 }
150 }
151
152 public byte[] read(String workflowname) throws SQLException {
153 byte[] wf = new byte[0];
154
155 Connection conn = null;
156
157 try {
158 conn = ds.getConnection();
159
160 PreparedStatement ps = conn.prepareStatement("SELECT " + wfDefinition + " FROM " + wfTable + " WHERE " + wfName + " = ?");
161 ps.setString(1, workflowname);
162
163 ResultSet rs = ps.executeQuery();
164
165 if (rs.next()) {
166 wf = rs.getBytes(1);
167 }
168
169 rs.close();
170 ps.close();
171 } finally {
172 try {
173 conn.close();
174 } catch (Exception ex) {
175 }
176 }
177
178 return wf;
179 }
180
181 public boolean removeWorkflow(String name) throws FactoryException {
182 boolean removed = false;
183
184 try {
185 Connection conn = ds.getConnection();
186 PreparedStatement ps = conn.prepareStatement("DELETE FROM " + wfTable + " WHERE " + wfName + " = ?");
187 ps.setString(1, name);
188
189 int rows = ps.executeUpdate();
190
191 if (rows == 1) {
192 removed = true;
193 workflows.remove(name);
194 }
195
196 ps.close();
197 conn.close();
198 } catch (SQLException e) {
199 throw new FactoryException("Unable to remove workflow: " + e.toString(), e);
200 }
201
202 return removed;
203 }
204
205 public boolean saveWorkflow(String name, WorkflowDescriptor descriptor, boolean replace) throws FactoryException {
206 WfConfig c = (WfConfig) workflows.get(name);
207
208 if ((c != null) && !replace) {
209 return false;
210 }
211
212 ByteArrayOutputStream bout = new ByteArrayOutputStream();
213 Writer out = new OutputStreamWriter(bout);
214
215 PrintWriter writer = new PrintWriter(out);
216 writer.println(WorkflowDescriptor.XML_HEADER);
217 writer.println(WorkflowDescriptor.DOCTYPE_DECL);
218 descriptor.writeXML(writer, 0);
219 writer.flush();
220 writer.close();
221
222 try {
224 return write(name, bout.toByteArray());
225 } catch (SQLException e) {
226 throw new FactoryException("Unable to save workflow: " + e.toString(), e);
227 } finally {
228 WfConfig config = new WfConfig(name);
229 workflows.put(name, config);
230 }
231 }
232
233 public boolean write(String workflowname, byte[] wf) throws SQLException {
234 boolean written = false;
235 Connection conn = null;
236
237 try {
238 conn = ds.getConnection();
239
240 PreparedStatement ps;
241
242 if (exists(workflowname, conn)) {
243 ps = conn.prepareStatement("UPDATE " + wfTable + " SET " + wfDefinition + " = ?" + "WHERE " + wfName + "= ?");
244
245 try {
246 ps.setBytes(1, wf);
247 } catch (Exception e) {
248 }
249
250 ps.setString(2, workflowname);
251 } else {
252 ps = conn.prepareStatement("INSERT INTO " + wfTable + " (" + wfName + ", " + wfDefinition + ") VALUES (?, ?)");
253 ps.setString(1, workflowname);
254
255 try {
256 ps.setBytes(2, wf);
257 } catch (Exception e) {
258 }
259 }
260
261 ps.executeUpdate();
262 ps.close();
263 conn.close();
264 written = true;
265 } finally {
266 try {
267 conn.close();
268 } catch (Exception e) {
269 }
270 }
271
272 return written;
273 }
274
275 private boolean exists(String workflowname, Connection conn) {
276 boolean exists = false;
277
278 try {
279 PreparedStatement ps = conn.prepareStatement("SELECT " + wfName + " FROM " + wfTable + " WHERE " + wfName + " = ?");
280 ps.setString(1, workflowname);
281
282 ResultSet rs = ps.executeQuery();
283
284 if (rs.next()) {
285 exists = true;
286 }
287
288 rs.close();
289 ps.close();
290 } catch (SQLException e) {
291 log.fatal("Could not check if [" + workflowname + "] exists", e);
292 }
293
294 return exists;
295 }
296
297 private void init() throws NamingException {
298 workflows = new HashMap ();
299
300 ds = (DataSource ) new InitialContext ().lookup(getProperties().getProperty("datasource"));
301 }
302
303 private WorkflowDescriptor load(final String wfName) throws IOException, SAXException , FactoryException {
304 byte[] wf = new byte[0];
305
306 try {
307 wf = read(wfName);
308 } catch (SQLException e) {
309 throw new FactoryException("Error loading workflow:" + e, e);
310 }
311
312 ByteArrayInputStream is = new ByteArrayInputStream(wf);
313
314 return WorkflowLoader.load(is);
315 }
316
317
319 class WfConfig {
320 String wfName;
321 WorkflowDescriptor descriptor;
322 long lastModified;
323
324 public WfConfig(String name) {
325 wfName = name;
326 }
327 }
328 }
329 |
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