fixed #271 result set reversal on backwards keyset pagination

Blazebit · Oct 22, 2016 · bbaeb28 · bbaeb28
1 parent 783ea02
commit bbaeb28
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Showing 2 changed files with 28 additions and 0 deletions.
diff --git a/core/impl/src/main/java/com/blazebit/persistence/impl/PaginatedTypedQuery.java b/core/impl/src/main/java/com/blazebit/persistence/impl/PaginatedTypedQuery.java
@@ -118,6 +118,11 @@ public PagedList<X> getResultList() {
 			}
 
 			List<X> queryResultList = objectQuery.getResultList();
+
+			if (keysetMode == KeysetMode.PREVIOUS) {
+				Collections.reverse(queryResultList);
+			}
+
 			PagedList<X> pagedResultList = new PagedListImpl<X>(queryResultList, newKeyset, totalSize, queryFirstResult, pageSize);
 			return pagedResultList;
 		} else {
@@ -141,6 +146,10 @@ public PagedList<X> getResultList() {
 				return new PagedListImpl<X>(newKeysetPage, totalSize, queryFirstResult, pageSize);
 			}
 
+			if (keysetMode == KeysetMode.PREVIOUS) {
+				Collections.reverse(result);
+			}
+
 			KeysetPage newKeyset = null;
 
 			if (keysetExtraction) {

diff --git a/core/testsuite/src/test/java/com/blazebit/persistence/testsuite/KeysetPaginationTest.java b/core/testsuite/src/test/java/com/blazebit/persistence/testsuite/KeysetPaginationTest.java
@@ -88,6 +88,25 @@ public void simpleNormalTest() {
         simpleTest(crit, pcb, result);
     }
 
+    @Test
+    public void backwardsPaginationResultSetOrder() {
+        CriteriaBuilder<Tuple> crit = cbf.create(em, Tuple.class).from(Document.class, "d")
+                .select("d.name").select("d.owner.name");
+        crit.orderByDesc("d.owner.name")
+                .orderByDesc("d.name")
+                .orderByAsc("d.id");
+
+        PaginatedCriteriaBuilder<Tuple> pcb = crit.page(null, 2, 1);
+        PagedList<Tuple> result = pcb.getResultList();
+
+        // scroll backwards
+        result = crit.page(result.getKeysetPage(), 0, 2).getResultList();
+
+        assertEquals(2, result.getSize());
+        assertEquals("doc3", result.get(0).get(0));
+        assertEquals("doc2", result.get(1).get(0));
+    }
+
     @Test
     public void testWithReferenceObject() {
         Document reference = cbf.create(em, Document.class).where("name").eq("doc3").getSingleResult();