Merge pull request #667 from gdarmont/pr-660

Fixes #660 : Can not fetch an object from Cursor when a RowBounds is used

Author: emacarron

src/main/java/org/apache/ibatis/cursor/defaults/DefaultCursor.java

@@ -191,10 +191,6 @@ private class CursorIterator implements Iterator<T> {
 
         @Override
         public boolean hasNext() {
-            if (isClosed()) {
-                return false;
-            }
-
             if (object == null) {
                 object = fetchNextUsingRowBound();
             }
@@ -203,10 +199,6 @@ public boolean hasNext() {
 
         @Override
         public T next() {
-            if (isClosed()) {
-                throw new CursorException("Cursor is closed");
-            }
-
             // Fill next with object fetched from hasNext()
             T next = object;
 

src/test/java/org/apache/ibatis/submitted/cursor_nested/CursorNestedTest.java

@@ -103,6 +103,7 @@ public void testCursorWithRowBound() {
 
             Iterator<User> iterator = usersCursor.iterator();
 
+            Assert.assertTrue(iterator.hasNext());
             User user = iterator.next();
             Assert.assertEquals("User3", user.getName());
             Assert.assertEquals(2, usersCursor.getCurrentIndex());

src/test/java/org/apache/ibatis/submitted/cursor_simple/CreateDB.sql

@@ -25,3 +25,4 @@ insert into users values(1, 'User1');
 insert into users values(2, 'User2');
 insert into users values(3, 'User3');
 insert into users values(4, 'User4');
+insert into users values(5, 'User5');

src/test/java/org/apache/ibatis/submitted/cursor_simple/CursorSimpleTest.java

@@ -33,6 +33,7 @@
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
+import java.util.NoSuchElementException;
 
 public class CursorSimpleTest {
 
@@ -93,6 +94,10 @@ public void shouldGetAllUser() {
             Assert.assertEquals("User4", user.getName());
             Assert.assertEquals(3, usersCursor.getCurrentIndex());
 
+            user = iterator.next();
+            Assert.assertEquals("User5", user.getName());
+            Assert.assertEquals(4, usersCursor.getCurrentIndex());
+
             // Check no more elements
             Assert.assertFalse(iterator.hasNext());
             Assert.assertFalse(usersCursor.isOpen());
@@ -140,26 +145,80 @@ public void testCursorWithRowBound() {
 
         try {
             // RowBound starting at offset 1 and limiting to 2 items
-            Cursor<User> usersCursor = sqlSession.selectCursor("getAllUsers", null, new RowBounds(1, 2));
+            Cursor<User> usersCursor = sqlSession.selectCursor("getAllUsers", null, new RowBounds(1, 3));
 
             Iterator<User> iterator = usersCursor.iterator();
 
             User user = iterator.next();
             Assert.assertEquals("User2", user.getName());
             Assert.assertEquals(1, usersCursor.getCurrentIndex());
 
+            // Calling hasNext() before next()
+            Assert.assertTrue(iterator.hasNext());
             user = iterator.next();
             Assert.assertEquals("User3", user.getName());
             Assert.assertEquals(2, usersCursor.getCurrentIndex());
 
+            // Calling next() without a previous hasNext() call
+            user = iterator.next();
+            Assert.assertEquals("User4", user.getName());
+            Assert.assertEquals(3, usersCursor.getCurrentIndex());
+
+            Assert.assertFalse(iterator.hasNext());
+            Assert.assertFalse(usersCursor.isOpen());
+            Assert.assertTrue(usersCursor.isConsumed());
+        } finally {
+            sqlSession.close();
+        }
+    }
+
+    @Test
+    public void testCursorIteratorNoSuchElementExceptionWithHasNext() {
+        SqlSession sqlSession = sqlSessionFactory.openSession();
+
+        Cursor<User> usersCursor = sqlSession.selectCursor("getAllUsers", null, new RowBounds(1, 1));
+        try {
+            Iterator<User> iterator = usersCursor.iterator();
+
+            User user = iterator.next();
+            Assert.assertEquals("User2", user.getName());
+            Assert.assertEquals(1, usersCursor.getCurrentIndex());
+
             Assert.assertFalse(iterator.hasNext());
+            iterator.next();
+            Assert.fail("We should have failed since we call next() when hasNext() returned false");
+        } catch (NoSuchElementException e) {
             Assert.assertFalse(usersCursor.isOpen());
             Assert.assertTrue(usersCursor.isConsumed());
         } finally {
             sqlSession.close();
         }
     }
 
+    @Test
+    public void testCursorIteratorNoSuchElementExceptionNoHasNext() {
+        SqlSession sqlSession = sqlSessionFactory.openSession();
+
+        Cursor<User> usersCursor = sqlSession.selectCursor("getAllUsers", null, new RowBounds(1, 1));
+        try {
+            Iterator<User> iterator = usersCursor.iterator();
+
+            User user = iterator.next();
+            Assert.assertEquals("User2", user.getName());
+            Assert.assertEquals(1, usersCursor.getCurrentIndex());
+
+            // Trying next() without hasNext()
+            iterator.next();
+            Assert.fail("We should have failed since we call next() when is no more items");
+        } catch (NoSuchElementException e) {
+            Assert.assertFalse(usersCursor.isOpen());
+            Assert.assertTrue(usersCursor.isConsumed());
+        } finally {
+            sqlSession.close();
+        }
+    }
+
+
     @Test
     public void testCursorWithBadRowBound() {
         SqlSession sqlSession = sqlSessionFactory.openSession();
@@ -285,8 +344,8 @@ public void testCursorUsageAfterClose() throws IOException {
             // trying next() will fail
             iterator.next();
 
-            Assert.fail("We should have failed since Cursor is closed");
-        } catch (CursorException e) {
+            Assert.fail("We should have failed with NoSuchElementException since Cursor is closed");
+        } catch (NoSuchElementException e) {
             // We had an exception and current index has not changed
             Assert.assertEquals(1, usersCursor.getCurrentIndex());
             return;
@@ -316,17 +375,19 @@ public void shouldGetAllUserUsingAnnotationBasedMapper() {
 
             Assert.assertFalse(usersCursor.isOpen());
             Assert.assertTrue(usersCursor.isConsumed());
-            Assert.assertEquals(3, usersCursor.getCurrentIndex());
+            Assert.assertEquals(4, usersCursor.getCurrentIndex());
 
-            Assert.assertEquals(4, userList.size());
+            Assert.assertEquals(5, userList.size());
             User user = userList.get(0);
             Assert.assertEquals("User1", user.getName());
             user = userList.get(1);
             Assert.assertEquals("User2", user.getName());
             user = userList.get(2);
             Assert.assertEquals("User3", user.getName());
-            user = userList.get(3);;
+            user = userList.get(3);
             Assert.assertEquals("User4", user.getName());
+            user = userList.get(4);
+            Assert.assertEquals("User5", user.getName());
 
         } finally {
             sqlSession.close();