Reversed out 18868: Transactional caches in nested transactions force the outer txn caches to drop new data

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@19002 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/repo/cache/CacheTest.java

@@ -157,41 +157,6 @@ public class CacheTest extends TestCase
         txnHelper.doInTransaction(callback);
     }
     
-    /**
-     * Make sure that an outer transaction gets to see cached data modified by an inner transaction.
-     */
-    public void testOuterTransactionStaleDataAvoidance() throws Throwable
-    {
-        final TransactionService transactionService = serviceRegistry.getTransactionService();
-        
-        RetryingTransactionCallback<Void> outer = new RetryingTransactionCallback<Void>()
-        {
-            public Void execute() throws Throwable
-            {
-                // Put a value in the cache
-                transactionalCache.put("A", "OUTER");
-                assertNotNull("Expected to get a value before inner txn.", transactionalCache.get("A"));
-                
-                RetryingTransactionCallback<Void> inner = new RetryingTransactionCallback<Void>()
-                {
-                    public Void execute() throws Throwable
-                    {
-                        // Just update the cache
-                        transactionalCache.put("A", "INNER");
-                        return null;
-                    }
-                };
-                // Do it in a nested txn
-                transactionService.getRetryingTransactionHelper().doInTransaction(inner, false, true);
-                
-                assertNull("Expected to *not* get a value after inner txn.", transactionalCache.get("A"));
-                
-                return null;
-            }
-        };
-        transactionService.getRetryingTransactionHelper().doInTransaction(outer);
-    }
-    
     public void testTransactionalCacheWithSingleTxn() throws Throwable
     {
         String newGlobalOne = "new_global_one";
@@ -374,7 +339,7 @@ public class CacheTest extends TestCase
     }
     
     /**
-     * Tests a straight Ehcache adapter against a transactional cache both in and outprojects/repository/source/java/org/alfresco/repo/cache/TransactionalCache.java
+     * Tests a straight Ehcache adapter against a transactional cache both in and out
      * of a transaction.  This is done repeatedly, pushing the count up.
      */
     public void testPerformance() throws Exception

source/java/org/alfresco/repo/cache/TransactionalCache.java

@@ -22,7 +22,6 @@ import java.io.Serializable;
 import java.util.Collection;
 import java.util.HashSet;
 import java.util.List;
-import java.util.Set;
 
 import net.sf.ehcache.Cache;
 import net.sf.ehcache.CacheException;
@@ -92,9 +91,6 @@ public class TransactionalCache<K extends Serializable, V extends Object>
     
     /** a unique string identifying this instance when binding resources */
     private String resourceKeyTxnData;
-    
-    /** Keep track of what transactions have been up to before */
-    private ThreadLocal<Set<TransactionData>> threadTxnData;
 
     /**
      * Public constructor.
@@ -103,7 +99,6 @@ public class TransactionalCache<K extends Serializable, V extends Object>
     {
         logger = LogFactory.getLog(TransactionalCache.class);
         isDebugEnabled = logger.isDebugEnabled();
-        threadTxnData = new ThreadLocal<Set<TransactionData>>();
     }
     
     /**
@@ -207,7 +202,7 @@ public class TransactionalCache<K extends Serializable, V extends Object>
         if (data == null)
         {
             String txnId = AlfrescoTransactionSupport.getTransactionId();
-            data = new TransactionData(txnId);
+            data = new TransactionData();
             // create and initialize caches
             data.updatedItemsCache = new Cache(
                     name + "_"+ txnId + "_updates",
@@ -215,7 +210,6 @@ public class TransactionalCache<K extends Serializable, V extends Object>
             data.removedItemsCache = new Cache(
                     name + "_" + txnId + "_removes",
                     maxCacheSize, false, true, 0, 0);
-            
             try
             {
                 cacheManager.addCache(data.updatedItemsCache);
@@ -232,15 +226,6 @@ public class TransactionalCache<K extends Serializable, V extends Object>
                 AlfrescoTransactionSupport.bindListener(this);
             }
             AlfrescoTransactionSupport.bindResource(resourceKeyTxnData, data);
-            
-            // Put the data into the set for potential inner transaction usage
-            Set<TransactionData> threadSet = threadTxnData.get();
-            if (threadSet == null)
-            {
-                threadSet = new HashSet<TransactionData>(3);
-                threadTxnData.set(threadSet);
-            }
-            threadSet.add(data);        // NB: This is removed during commit or rollback
         }
         return data;
     }
@@ -700,15 +685,6 @@ public class TransactionalCache<K extends Serializable, V extends Object>
         finally
         {
             removeCaches(txnData);
-            
-            // Remove our txnData entry from the thread
-            Set<TransactionData> threadSet = threadTxnData.get();
-            threadSet.remove(txnData);
-            // We pessimistically kill all new data cached by other transactions
-            for (TransactionData outerTxnData : threadSet)
-            {
-                outerTxnData.removeUpdates();
-            }
         }
     }
 
@@ -720,10 +696,6 @@ public class TransactionalCache<K extends Serializable, V extends Object>
         TransactionData txnData = getTransactionData();
         // drop caches from cachemanager
         removeCaches(txnData);
-        
-        // Remove our txnData entry from the thread
-        Set<TransactionData> threadSet = threadTxnData.get();
-        threadSet.remove(txnData);
     }
     
     /**
@@ -880,57 +852,10 @@ public class TransactionalCache<K extends Serializable, V extends Object>
     /** Data holder to bind data to the transaction */
     private class TransactionData
     {
-        /** A thread-locally unique ID */
-        private String id;
-        
         private Cache updatedItemsCache;
         private Cache removedItemsCache;
         private boolean haveIssuedFullWarning;
         private boolean isClearOn;
         private boolean isClosed;
-        
-        private TransactionData(String id)
-        {
-            this.id = id;
-        }
-
-        @Override
-        public String toString()
-        {
-            StringBuilder builder = new StringBuilder();
-            builder.append("TransactionData [id=").append(id).append("]");
-            return builder.toString();
-        }
-
-        @Override
-        public int hashCode()
-        {
-            return id.hashCode();
-        }
-
-        /**
-         * Controlled implementation of equals i.e. we don't check all conditions; the containing
-         * class needs to ensure types don't get mixed in sets, etc.
-         */
-        @Override
-        public boolean equals(Object obj)
-        {
-            if (this == obj)
-            {
-                return true;
-            }
-            TransactionData other = (TransactionData) obj;
-            return id.equals(other.id);
-        }
-        
-        /**
-         * Pessimistic method that removes all updates and additions from the local
-         * transactional data.  This method is used when inner transactions are started
-         * that modify the cache.
-         */
-        private void removeUpdates()
-        {
-            updatedItemsCache.removeAll();
-        }
     }
 }