OPENJPA-1821: Defensive thread guard on reparametrization.

git-svn-id: https://svn.apache.org/repos/asf/openjpa/trunk@1028488 13f79535-47bb-0310-9956-ffa450edef68

openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/kernel/PreparedSQLStoreQuery.java

@@ -152,7 +152,7 @@ public class PreparedSQLStoreQuery extends SQLStoreQuery {
          * 
          * @see PreparedQueryImpl#reparametrize(Map, org.apache.openjpa.kernel.Broker)
          */
-        public Object[] toParameterArray(StoreQuery q, Map userParams) {
+        public synchronized Object[] toParameterArray(StoreQuery q, Map userParams) {
             Object[] array = new Object[userParams.size()];
 
             Set<Map.Entry<Object,Object>> userSet = userParams.entrySet();

openjpa-persistence-jdbc/src/test/java/org/apache/openjpa/persistence/jdbc/sqlcache/TestMultithreadedReparametrization.java

@@ -0,0 +1,133 @@
+/*
+ * 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.sqlcache;
+
+import java.util.List;
+import java.util.Properties;
+
+import javax.persistence.EntityManager;
+import javax.persistence.TypedQuery;
+
+import junit.framework.TestCase;
+
+import org.apache.openjpa.kernel.QueryStatistics;
+import org.apache.openjpa.persistence.OpenJPAEntityManagerFactory;
+import org.apache.openjpa.persistence.OpenJPAPersistence;
+
+/**
+ * Test reparameterization of cached query under heavy load. 
+ * 
+ * @author Pinaki Poddar
+ *
+ */
+public class TestMultithreadedReparametrization extends TestCase {
+    private static String RESOURCE = "META-INF/persistence.xml"; 
+    private static String UNIT_NAME = "PreparedQuery";
+    protected static OpenJPAEntityManagerFactory emf;
+    
+    public void setUp() throws Exception {
+        super.setUp();
+        if (emf == null) {
+            Properties config = new Properties();
+            config.put("openjpa.Log", "SQL=WARN");
+            config.put("openjpa.jdbc.QuerySQLCache", "true(EnableStatistics=true)");
+            config.put("openjpa.ConnectionFactoryProperties", "PrintParameters=true");
+            emf = OpenJPAPersistence.createEntityManagerFactory(UNIT_NAME, RESOURCE, config);
+        }
+    }
+    
+    public void testReparametrizationUnderHeavyLoad() throws Exception {
+        long baseId = System.currentTimeMillis();
+        EntityManager em = emf.createEntityManager();
+        em.getTransaction().begin();
+        int nThreads = 80;
+        for (int i = 0; i < nThreads; i++) {
+            Person p = new Person();
+            p.setId(baseId+i);
+            p.setFirstName("First"+i);
+            p.setLastName("Last"+i);
+            p.setAge((short)(20+i));
+            em.persist(p);
+        }
+        em.getTransaction().commit();
+    
+        String jpql = "select p from Person p " 
+                    + "where p.id=:id and p.firstName=:first and p.lastName=:last and p.age=:age";
+        int nRepeats = 20;
+        Thread[] threads = new Thread[nThreads];
+        for (int i = 0; i < nThreads; i++) {
+            Object[] args = {"id", baseId+i, "first", "First"+i, "last", "Last"+i, "age", (short)(20+i)};
+            QueryThread thread = new QueryThread(emf.createEntityManager(), jpql, args, nRepeats);
+            threads[i] = new Thread(thread);
+        }
+        for (Thread thread : threads) {
+            thread.start();
+        }
+        for (Thread thread : threads) {
+            thread.join();
+        }
+        QueryStatistics<String> stats = emf.getConfiguration().getQuerySQLCacheInstance().getStatistics();
+        assertEquals(nThreads*nRepeats,stats.getExecutionCount(), stats.getExecutionCount(jpql));
+        assertEquals(nThreads*nRepeats-1,stats.getExecutionCount(), stats.getHitCount(jpql));
+        
+    }
+    
+    /**
+     * Each thread executes same query with same parameters repeatedly.
+     * 
+     * @author Pinaki Poddar
+     *
+     */
+    public static class QueryThread implements Runnable {
+        public final EntityManager em;
+        public final String jpql;
+        public final Object[] args;
+        public final int nTimes;
+        public QueryThread(EntityManager em, String jpql, Object[] args, int r) {
+            this.em = em;
+            this.jpql = jpql;
+            this.args = args;
+            this.nTimes = r;
+        }
+        
+        public void run()  {
+            try {
+            for (int i = 0; i < nTimes; i++) {
+                TypedQuery<Person> q = em.createQuery(jpql, Person.class);
+                for (int j = 0; j < args.length; j += 2) {
+                    q.setParameter(args[j].toString(), args[j+1]);
+                }
+                List<Person> result = q.getResultList();
+                assertEquals(Thread.currentThread() + " failed", 1, result.size());
+                Person p = result.get(0);
+                assertEquals(args[1], p.getId());
+                assertEquals(args[3], p.getFirstName());
+                assertEquals(args[5], p.getLastName());
+                assertEquals(args[7], p.getAge());
+                
+            }
+            } catch (Exception ex) {
+                ex.printStackTrace();
+                fail();
+            }
+        }
+        
+    }
+}