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1
7 package org.jboss.cache.interceptors;
8
9 import org.jboss.cache.CacheException;
10 import org.jboss.cache.Fqn;
11 import org.jboss.cache.GlobalTransaction;
12 import org.jboss.cache.InvocationContext;
13 import org.jboss.cache.NodeSPI;
14 import org.jboss.cache.marshall.MethodCall;
15 import org.jboss.cache.marshall.MethodDeclarations;
16 import org.jboss.cache.optimistic.DataVersioningException;
17 import org.jboss.cache.optimistic.DefaultDataVersion;
18 import org.jboss.cache.optimistic.TransactionWorkspace;
19 import org.jboss.cache.optimistic.WorkspaceNode;
20
21 import javax.transaction.Transaction  ;
22 import java.util.Collection ;
23 import java.util.Map ;
24
25
42 public class OptimisticValidatorInterceptor extends OptimisticInterceptor
43 {
44 public Object invoke(MethodCall m) throws Throwable
45 {
46 if (MethodDeclarations.isBuddyGroupOrganisationMethod(m.getMethodId())) return super.invoke(m);
48
49 InvocationContext ctx = cache.getInvocationContext();
50 Transaction tx = ctx.getTransaction();
51 GlobalTransaction gtx = ctx.getGlobalTransaction();
52 Object retval = null;
53
54 if (tx == null)
55 {
56 throw new CacheException("Not in a transaction");
57 }
58
59 switch (m.getMethodId())
62 {
63 case MethodDeclarations.optimisticPrepareMethod_id:
64 validateNodes(gtx);
66 break;
67 case MethodDeclarations.commitMethod_id:
68 commit(gtx);
69 break;
70 case MethodDeclarations.rollbackMethod_id:
71 rollBack(gtx);
72 break;
73 default:
74 retval = super.invoke(m);
75 break;
76 }
77 return retval;
78 }
79
80
81 private void validateNodes(GlobalTransaction gtx) throws CacheException
82 {
83 TransactionWorkspace workspace;
84
85 try
86 {
87 workspace = getTransactionWorkspace(gtx);
88 }
89 catch (CacheException e)
90 {
91 throw new CacheException("unable to retrieve workspace", e);
92 }
93
94 Collection <WorkspaceNode> nodes = workspace.getNodes().values();
96
97 if (log.isDebugEnabled()) log.debug("validating nodes. Num nodes: " + nodes.size());
99 simpleValidate(nodes);
100 log.debug("validated nodes");
101 }
102
103 private void simpleValidate(Collection <WorkspaceNode> nodes) throws DataVersioningException
104 {
105 boolean trace = log.isTraceEnabled();
106 for (WorkspaceNode workspaceNode : nodes)
107 {
108 Fqn fqn = workspaceNode.getFqn();
109 if (trace) log.trace("Validating version for node " + fqn);
110
111 NodeSPI realNode;
112 realNode = cache.peek(fqn);
113
114 if (realNode == null && !workspaceNode.isCreated())
117 {
118 throw new DataVersioningException("Real node for " + fqn + " is null, and this wasn't newly created in this tx!");
119 }
120
121 if (realNode != null && workspaceNode.isCreated())
122 {
123 throw new DataVersioningException("Tx attempted to create " + fqn + " anew. It has already been created since this tx started by another (possibly remote) tx.");
124 }
125
126 if (!workspaceNode.isCreated() && (workspaceNode.isDeleted() || workspaceNode.isDirty()))
127 {
128 if (!realNode.getVersion().getClass().equals(workspaceNode.getVersion().getClass()) && checkNotInitialRootVersion(realNode))
130 {
131 throw new DataVersioningException("Attempting to apply data version of type " + workspaceNode.getVersion().getClass() + " to a node [fqn = " + realNode.getFqn() + "] that already contains version of type " + realNode.getVersion().getClass());
132 }
133 if (realNode.getVersion().newerThan(workspaceNode.getVersion()))
134 {
135 throw new DataVersioningException("DataNode [" + fqn + "] version " + workspaceNode.getNode().getVersion() + " is newer than workspace node " + workspaceNode.getVersion());
137 }
138 }
139 }
140 }
141
142 private boolean checkNotInitialRootVersion(NodeSPI n)
143 {
144 return !n.getFqn().isRoot() || !(n.getVersion() instanceof DefaultDataVersion) || n.getVersion() != DefaultDataVersion.ZERO;
145 }
146
147 private void commit(GlobalTransaction gtx)
148 {
149 TransactionWorkspace workspace;
150
151 try
152 {
153 workspace = getTransactionWorkspace(gtx);
154 }
155 catch (CacheException e)
156 {
157 log.trace("we can't rollback", e);
158 return;
159 }
160
161 log.debug("commiting validated changes ");
162 Collection <WorkspaceNode> nodes = workspace.getNodes().values();
164
165 boolean trace = log.isTraceEnabled();
166 for (WorkspaceNode wrappedNode : nodes)
167 {
168 if (wrappedNode.isDeleted())
170 {
171 if (trace) log.trace("Workspace node " + wrappedNode.getFqn() + " deleted; removing");
172 NodeSPI dNode = wrappedNode.getNode();
173
174
175 if (dNode.getFqn().isRoot())
176 {
177 log.warn("Attempted to delete the root node");
178 }
179 else
180 {
181 NodeSPI parent = dNode.getParent();
182 if (parent == null)
183 {
184 throw new IllegalStateException ("dNode " + dNode + " has no parent");
185 }
186
187 parent.removeChildDirect(dNode.getFqn().getLastElement());
188 }
189 }
190 else
191 {
192 if (wrappedNode.isDirty())
195 {
196 NodeSPI current = wrappedNode.getNode();
197 Map mergedChildren = wrappedNode.getMergedChildren();
198
199 current.setChildrenMapDirect(mergedChildren);
201
202 Map mergedData = wrappedNode.getMergedData();
205
206 current.clearDataDirect();
207 current.putDirect(mergedData);
208
209 if (wrappedNode.isVersioningImplicit())
210 {
211 if (trace) log.trace("Versioning is implicit; incrementing.");
212 current.setVersion(((DefaultDataVersion) wrappedNode.getVersion()).increment());
213 }
214 else
215 {
216 if (trace) log.trace("Versioning is explicit; not attempting an increment.");
217 current.setVersion(wrappedNode.getVersion());
218 }
219 if (trace)
220 {
221 log.trace("Setting version of node " + current.getFqn() + " from " + wrappedNode.getVersion() + " to " + current.getVersion());
222 }
223 }
224 else
225 {
226 if (trace)
227 {
228 log.trace("Merging node " + wrappedNode.getFqn() + " not necessary since the node is not dirty");
229 }
230 }
231 }
232 }
233
234 }
235
236 private void rollBack(GlobalTransaction gtx)
237 {
238 TransactionWorkspace workspace;
239 try
240 {
241 workspace = getTransactionWorkspace(gtx);
242 Map nodes = workspace.getNodes();
243 nodes.clear();
244 }
245 catch (CacheException e)
246 {
247 log.info("Unable to roll back", e);
248 }
249 }
250 }
251 |
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