Fix for #318. Merged from 3.2.x branch

Author: emacarron

src/main/java/org/apache/ibatis/executor/resultset/DefaultResultSetHandler.java

@@ -445,15 +445,17 @@ private boolean applyAutomaticMappings(ResultSetWrapper rsw, ResultMap resultMap
   private void linkToParents(ResultSet rs, ResultMapping parentMapping, Object rowValue) throws SQLException {
     CacheKey parentKey = createKeyForMultipleResults(rs, parentMapping, parentMapping.getColumn(), parentMapping.getForeignColumn());
     List<PendingRelation> parents = pendingRelations.get(parentKey);
-    for (PendingRelation parent : parents) {
-      if (parent != null) {
-        final Object collectionProperty = instantiateCollectionPropertyIfAppropriate(parent.propertyMapping, parent.metaObject);
-        if (rowValue != null) {
-          if (collectionProperty != null) {
-            final MetaObject targetMetaObject = configuration.newMetaObject(collectionProperty);
-            targetMetaObject.add(rowValue);
-          } else {
-            parent.metaObject.setValue(parent.propertyMapping.getProperty(), rowValue);
+    if (parents != null) {
+      for (PendingRelation parent : parents) {
+        if (parent != null) {
+          final Object collectionProperty = instantiateCollectionPropertyIfAppropriate(parent.propertyMapping, parent.metaObject);
+          if (rowValue != null) {
+            if (collectionProperty != null) {
+              final MetaObject targetMetaObject = configuration.newMetaObject(collectionProperty);
+              targetMetaObject.add(rowValue);
+            } else {
+              parent.metaObject.setValue(parent.propertyMapping.getProperty(), rowValue);
+            }
           }
         }
       }

src/test/java/org/apache/ibatis/submitted/multipleresultsetswithassociation/CreateDB3.sql

@@ -16,6 +16,8 @@
         VALUES (1, 'Fred');
     INSERT INTO order_header(order_id, cust_name)
         VALUES (2, 'Barney');
+    INSERT INTO order_header(order_id, cust_name)
+        VALUES (3, 'Homer');        
 
     INSERT INTO order_detail(order_id, line_number, quantity, item_description)
         VALUES (1, 1, 1, 'Pen');