fix(hstore): restore backend range page state

Author: contrueCT

hugegraph-server/hugegraph-hstore/src/main/java/org/apache/hugegraph/backend/store/hstore/HstoreTable.java

@@ -114,12 +114,10 @@ private static boolean direction(Condition condition) {
 
     protected static BackendEntryIterator newEntryIterator(
             BackendColumnIterator cols, Query query) {
-        BiFunction<BackendEntry, BackendColumn, BackendEntry> merger =
-                (entry, col) -> mergeColumn(query, entry, col);
-        if (query.resultType().isRangeIndex()) {
-            return new RangeIndexEntryIterator(cols, query, merger);
-        }
-        return new BinaryEntryIterator<>(cols, query, merger);
+        return new BinaryEntryIterator<>(cols, query,
+                                         (entry, col) -> mergeColumn(query,
+                                                                     entry,
+                                                                     col));
     }
 
     protected static BackendEntryIterator newEntryIteratorOlap(
@@ -146,31 +144,6 @@ private static BackendEntry mergeColumn(Query query, BackendEntry entry,
         return entry;
     }
 
-    private static final class RangeIndexEntryIterator
-            extends BinaryEntryIterator<BackendColumn> {
-
-        private byte[] lastPosition;
-
-        private RangeIndexEntryIterator(
-                BackendColumnIterator cols, Query query,
-                BiFunction<BackendEntry, BackendColumn, BackendEntry> merger) {
-            super(cols, query, merger);
-            this.lastPosition = PageState.EMPTY_BYTES;
-        }
-
-        @Override
-        public BackendEntry next() {
-            BackendEntry entry = super.next();
-            this.lastPosition = entry.id().asBytes();
-            return entry;
-        }
-
-        @Override
-        protected PageState pageState() {
-            return new PageState(this.lastPosition, 0, (int) this.count());
-        }
-    }
-
     public static String bytes2String(byte[] bytes) {
         StringBuilder result = new StringBuilder();
         for (byte b : bytes) {

hugegraph-server/hugegraph-hstore/src/test/java/org/apache/hugegraph/backend/store/hstore/HstoreTableTest.java

@@ -39,7 +39,7 @@
 public class HstoreTableTest {
 
     @Test
-    public void testRangeIndexPageStateIgnoresPrefetchedColumn() {
+    public void testRangeIndexPageStateComesFromBackendIteratorPosition() {
         Query query = new Query(HugeType.RANGE_INT_INDEX);
         query.page("");
         query.limit(1L);
@@ -52,7 +52,7 @@ public void testRangeIndexPageStateIgnoresPrefetchedColumn() {
         Assert.assertArrayEquals(keyBytes(1), entry.id().asBytes());
 
         PageState pageState = PageInfo.pageState(iterator);
-        Assert.assertArrayEquals(keyBytes(1), pageState.position());
+        Assert.assertArrayEquals(keyBytes(2), pageState.position());
         Assert.assertEquals(1L, pageState.total());
     }