From 13e3c48caea0c7c8125b72f398f6443ce231902f Mon Sep 17 00:00:00 2001
From: Fay Wang <faywang@apache.org>
Date: Thu, 18 Mar 2010 23:52:33 +0000
Subject: [PATCH] OPENJPA-1580: disable query cache when pagination is
 involved.

git-svn-id: https://svn.apache.org/repos/asf/openjpa/trunk@925048 13f79535-47bb-0310-9956-ffa450edef68
---
 .../jdbc/kernel/PreparedQueryImpl.java        | 16 +++++++++++++--
 .../openjpa/jdbc/kernel/localizer.properties  |  4 +++-
 .../jdbc/sqlcache/TestPreparedQueryCache.java | 20 +++++++++++++++++++
 3 files changed, 37 insertions(+), 3 deletions(-)

diff --git a/openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/kernel/PreparedQueryImpl.java b/openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/kernel/PreparedQueryImpl.java
index 67fabc80a..558e8569e 100644
--- a/openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/kernel/PreparedQueryImpl.java
+++ b/openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/kernel/PreparedQueryImpl.java
@@ -178,10 +178,14 @@ public class PreparedQueryImpl implements PreparedQuery {
         SQLBuffer buffer = selector.getSQL();
         if (buffer == null)
             return new PreparedQueryCacheImpl.StrongExclusion(_id, _loc.get("exclude-no-sql", _id).getMessage());;
-        boolean useFieldStrategy = isUsingFieldStrategy(); 
-        if (useFieldStrategy)
+        if (isUsingFieldStrategy())
             return new PreparedQueryCacheImpl.StrongExclusion(_id, 
                 _loc.get("exclude-user-strategy", _id).getMessage());;
+                
+        if (isPaginated())
+            return new PreparedQueryCacheImpl.StrongExclusion(_id, 
+                _loc.get("exclude-pagination", _id).getMessage());;
+
         setTargetQuery(buffer.getSQL());
         setParameters(buffer.getParameters());
         setUserParameterPositions(buffer.getUserParameters());
@@ -259,6 +263,14 @@ public class PreparedQueryImpl implements PreparedQuery {
         return false;
     }
     
+    private boolean isPaginated() {
+        if (select instanceof SelectImpl) {
+            if (((SelectImpl)select).getStartIndex() != 0 || 
+                ((SelectImpl)select).getEndIndex() != Long.MAX_VALUE)
+                return true;
+        }
+        return false;
+    }        
     private boolean isUsingFieldStrategy() {
         for (int i = 0; i < _exps.length; i++) {
             if (isUsingFieldStrategy(_exps[i])) {
diff --git a/openjpa-jdbc/src/main/resources/org/apache/openjpa/jdbc/kernel/localizer.properties b/openjpa-jdbc/src/main/resources/org/apache/openjpa/jdbc/kernel/localizer.properties
index e925ed7b9..5bb99f68a 100644
--- a/openjpa-jdbc/src/main/resources/org/apache/openjpa/jdbc/kernel/localizer.properties
+++ b/openjpa-jdbc/src/main/resources/org/apache/openjpa/jdbc/kernel/localizer.properties
@@ -168,4 +168,6 @@ exclude-not-executor: Query "{0}" is not cached because it was not executed on a
 exclude-externalized-param: Query "{0}" is not cached because some parameterized \
     field values are externalized.  
 exclude-user-strategy: This query "{0}" is not cached because some parameterized \
-    field value depends on user-defined field strategy.        
\ No newline at end of file
+    field value depends on user-defined field strategy.        
+exclude-pagination: This query "{0}" involves pagination and is not cached.
+      
\ No newline at end of file
diff --git a/openjpa-persistence-jdbc/src/test/java/org/apache/openjpa/persistence/jdbc/sqlcache/TestPreparedQueryCache.java b/openjpa-persistence-jdbc/src/test/java/org/apache/openjpa/persistence/jdbc/sqlcache/TestPreparedQueryCache.java
index 59b88a1f6..c65b0fa2c 100644
--- a/openjpa-persistence-jdbc/src/test/java/org/apache/openjpa/persistence/jdbc/sqlcache/TestPreparedQueryCache.java
+++ b/openjpa-persistence-jdbc/src/test/java/org/apache/openjpa/persistence/jdbc/sqlcache/TestPreparedQueryCache.java
@@ -974,7 +974,27 @@ public class TestPreparedQueryCache extends TestCase {
         em.getTransaction().rollback();
     }
 
+    public void testRangeIsExcluded() {
+        List<Company> l = null;
 
+        l = getAllCompaniesPaged(0, 1);
+        assertEquals(1, l.size());
+        assertEquals("acme.org", l.get(0).getName());
+        l = getAllCompaniesPaged(1, 1);
+        assertEquals(1, l.size());
+        assertEquals("BEA", l.get(0).getName());
+        l = getAllCompaniesPaged(2, 1);
+        assertEquals(1, l.size());
+        assertEquals("IBM", l.get(0).getName());
+    }
+
+    public List<Company> getAllCompaniesPaged(int start, int max) {
+        EntityManager em = emf.createEntityManager();
+        Query q = em.createQuery("select p from Company p order by p.name");
+        q.setFirstResult(start);
+        q.setMaxResults(max);
+        return (List<Company>) q.getResultList();
+    }
     
     PreparedQueryCache getPreparedQueryCache() {
         return emf.getConfiguration().getQuerySQLCacheInstance();