OPENJPA-2235: READ_UNCOMMITTED setting for the fetch plan isolation level is ignored in DB2Dictionary - applied Helen Xu's patch to trunk.

git-svn-id: https://svn.apache.org/repos/asf/openjpa/trunk@1426352 13f79535-47bb-0310-9956-ffa450edef68

openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/sql/DB2Dictionary.java

@@ -382,7 +382,8 @@ public class DB2Dictionary
 
     /**
      * Get the update clause for the query based on the
-     * updateClause and isolationLevel hints
+     * isolationLevel hints if it is for update.
+     * It also handles the UR hint when it is not for update.
      */
     protected String getForUpdateClause(JDBCFetchConfiguration fetch,
         boolean isForUpdate, Select sel) {
@@ -435,6 +436,11 @@ public class DB2Dictionary
                 }
                 break;
             }
+        } else {
+        	if ( fetch != null && fetch.getIsolation() == Connection.TRANSACTION_READ_UNCOMMITTED ) {
+	            forUpdateString.append(" ").append(forReadOnlyClause)
+	            .append(" ").append(withURClause);
+	    	}
         }
    
         return forUpdateString.toString();

openjpa-persistence-jdbc/src/test/java/org/apache/openjpa/persistence/jdbc/TestIsolationFecthHint.java

@@ -0,0 +1,61 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.apache.openjpa.persistence.jdbc;
+
+import javax.persistence.Query;
+
+import org.apache.openjpa.jdbc.conf.JDBCConfiguration;
+import org.apache.openjpa.jdbc.sql.DB2Dictionary;
+import org.apache.openjpa.jdbc.sql.DBDictionary;
+import org.apache.openjpa.persistence.OpenJPAEntityManagerSPI;
+import org.apache.openjpa.persistence.simple.AllFieldTypes;
+import org.apache.openjpa.persistence.test.SQLListenerTestCase;
+
+public class TestIsolationFecthHint extends SQLListenerTestCase{
+	
+	public void setUp(){
+		setUp(AllFieldTypes.class, CLEAR_TABLES);
+		
+	}	
+
+    public void testFetchPlanIsolationURHint(){
+    	OpenJPAEntityManagerSPI em = emf.createEntityManager();     
+        try {
+        	DBDictionary dict = ((JDBCConfiguration) em.getConfiguration())
+                    .getDBDictionaryInstance();
+        	 if (dict instanceof DB2Dictionary) {
+        		 AllFieldTypes allFieldTypes = new AllFieldTypes();
+            	allFieldTypes.setStringField("testString");
+            	allFieldTypes.setIntField(2012);
+            	
+            	em.getTransaction().begin();
+            	em.persist(allFieldTypes);
+            	Query query = em.createQuery("select e from AllFieldTypes e where e.stringField = ?1");
+            	query.setParameter(1, "testString");
+            	query.setHint("openjpa.FetchPlan.Isolation", "READ_UNCOMMITTED");
+            	assertEquals(1, query.getResultList().size());
+            	assertContainsSQL("FOR READ ONLY WITH UR");
+            	em.getTransaction().rollback();
+    		}
+        } finally {
+        	em.close();
+        }
+    }
+}