Mapping nested cursor to constructor arg

Author: harawata

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

@@ -569,7 +569,9 @@ private Object getPropertyMappingValue(ResultSet rs, MetaObject metaResultObject
       return getNestedQueryMappingValue(rs, metaResultObject, propertyMapping, lazyLoader, columnPrefix);
     }
     if (JdbcType.CURSOR.equals(propertyMapping.getJdbcType())) {
-      return getNestedCursorValue(rs, metaResultObject, propertyMapping, columnPrefix);
+      List<Object> results = getNestedCursorValue(rs, propertyMapping, columnPrefix);
+      linkObjects(metaResultObject, propertyMapping, results.get(0), true);
+      return metaResultObject.getValue(propertyMapping.getProperty());
     }
     if (propertyMapping.getResultSet() != null) {
       addPendingChildRelation(rs, metaResultObject, propertyMapping); // TODO is that OK?
@@ -581,18 +583,16 @@ private Object getPropertyMappingValue(ResultSet rs, MetaObject metaResultObject
     }
   }
 
-  private Object getNestedCursorValue(ResultSet rs, MetaObject metaResultObject, ResultMapping propertyMapping,
-      String parentColumnPrefix) throws SQLException {
+  private List<Object> getNestedCursorValue(ResultSet rs, ResultMapping propertyMapping, String parentColumnPrefix)
+      throws SQLException {
     final String column = prependPrefix(propertyMapping.getColumn(), parentColumnPrefix);
-    final String property = propertyMapping.getProperty();
     ResultMap nestedResultMap = resolveDiscriminatedResultMap(rs,
         configuration.getResultMap(propertyMapping.getNestedResultMapId()),
         getColumnPrefix(parentColumnPrefix, propertyMapping));
     ResultSetWrapper rsw = new ResultSetWrapper(rs.getObject(column, ResultSet.class), configuration);
     List<Object> results = new ArrayList<>();
     handleResultSet(rsw, nestedResultMap, results, null);
-    linkObjects(metaResultObject, propertyMapping, results.get(0), true);
-    return metaResultObject.getValue(property);
+    return results;
   }
 
   private List<UnMappedColumnAutoMapping> createAutomaticMappings(ResultSetWrapper rsw, ResultMap resultMap,
@@ -778,6 +778,15 @@ Object createParameterizedResultObject(ResultSetWrapper rsw, Class<?> resultType
       try {
         if (constructorMapping.getNestedQueryId() != null) {
           value = getNestedQueryConstructorValue(rsw.getResultSet(), constructorMapping, columnPrefix);
+        } else if (JdbcType.CURSOR.equals(constructorMapping.getJdbcType())) {
+          List<?> result = (List<?>) getNestedCursorValue(rsw.getResultSet(), constructorMapping, columnPrefix).get(0);
+          if (objectFactory.isCollection(parameterType)) {
+            MetaObject collection = configuration.newMetaObject(objectFactory.create(parameterType));
+            collection.addAll((List<?>) result);
+            value = collection.getOriginalObject();
+          } else {
+            value = toSingleObj(result);
+          }
         } else if (constructorMapping.getNestedResultMapId() != null) {
           final String constructorColumnPrefix = getColumnPrefix(columnPrefix, constructorMapping);
           final ResultMap resultMap = resolveDiscriminatedResultMap(rsw.getResultSet(),

src/test/java/org/apache/ibatis/submitted/oracle_cursor/Mapper.java

@@ -33,8 +33,12 @@ public interface Mapper {
 
   List<Author> selectNestedCursor_Automap();
 
+  List<Author> selectNestedCursorConstructorCollection();
+
   List<Author2> selectNestedCursorOfStrings();
 
   List<Book2> selectNestedCursorAssociation();
 
+  List<Book2> selectNestedCursorConstructorAssociation();
+
 }

src/test/java/org/apache/ibatis/submitted/oracle_cursor/OracleCursorTest.java

@@ -88,6 +88,11 @@ void nestedCursors_Automap() {
     doTest(Mapper::selectNestedCursor_Automap);
   }
 
+  @Test
+  void nestedCursorsConstructorCollection() {
+    doTest(Mapper::selectNestedCursorConstructorCollection);
+  }
+
   private void doTest(Function<Mapper, List<Author>> query) {
     doTest(query, ArrayList.class);
   }
@@ -116,9 +121,18 @@ void nestedCursorOfStrings() {
 
   @Test
   void nestedCursorAssociation() {
+    doTestBook2(Mapper::selectNestedCursorAssociation);
+  }
+
+  @Test
+  void nestedCursorConstructorAssociation() {
+    doTestBook2(Mapper::selectNestedCursorConstructorAssociation);
+  }
+
+  private void doTestBook2(Function<Mapper, List<Book2>> query) {
     try (SqlSession sqlSession = sqlSessionFactory.openSession()) {
       Mapper mapper = sqlSession.getMapper(Mapper.class);
-      List<Book2> books = mapper.selectNestedCursorAssociation();
+      List<Book2> books = query.apply(mapper);
       assertIterableEquals(List.of(new Book2(1, "C#", new Author(1, "John")),
           new Book2(2, "Python", new Author(1, "John")), new Book2(3, "SQL", new Author(2, "Jane")),
           new Book2(4, "Java", new Author(2, "Jane")), new Book2(5, "Ruby", new Author(1, "John"))), books);

src/test/resources/org/apache/ibatis/submitted/oracle_cursor/Mapper.xml

@@ -112,6 +112,22 @@
     <include refid="nestedCursor" />
   </select>
 
+  <!-- Map nested cursor to constructor arg (collection). -->
+  <resultMap id="authorRM_ConstructorCollection"
+    type="org.apache.ibatis.submitted.oracle_cursor.Author">
+    <constructor>
+      <idArg column="id" javaType="int" />
+      <arg column="name" javaType="string" />
+      <arg column="books" jdbcType="CURSOR"
+        javaType="list" resultMap="bookRM" />
+    </constructor>
+  </resultMap>
+
+  <select id="selectNestedCursorConstructorCollection"
+    resultMap="authorRM_ConstructorCollection">
+    <include refid="nestedCursor" />
+  </select>
+
   <!-- Use inline result map to map nested cursor to collection. -->
   <resultMap id="author2RM_InlineRM"
     type="org.apache.ibatis.submitted.oracle_cursor.Author2">
@@ -130,21 +146,52 @@
     ) book_names from author a
   ]]></select>
 
+  <sql id="bookNestedCursor"><![CDATA[
+    select b.id, b.name, cursor(
+      select a.id, a.name from author a where b.author_id = a.id
+    ) author from book b
+  ]]></sql>
+
   <!-- Map nested cursor to association. -->
   <resultMap id="book2RM_Association"
     type="org.apache.ibatis.submitted.oracle_cursor.Book2">
     <id property="id" column="id" />
     <result property="name" column="name" />
-    <association property="author" column="author" jdbcType="CURSOR">
+    <association property="author" column="author"
+      jdbcType="CURSOR" resultMap="authorRM">
       <id property="id" column="id" />
       <result property="name" column="name" />
     </association>
   </resultMap>
 
   <select id="selectNestedCursorAssociation"
-    resultMap="book2RM_Association"><![CDATA[
-    select b.id, b.name, cursor(
-      select a.id, a.name from author a where b.author_id = a.id
-    ) author from book b
-  ]]></select>
+    resultMap="book2RM_Association">
+    <include refid="bookNestedCursor" />
+  </select>
+
+  <resultMap id="authorRM_ConstructorIdName"
+    type="org.apache.ibatis.submitted.oracle_cursor.Author">
+    <constructor>
+      <idArg column="id" javaType="int" />
+      <arg column="name" javaType="string" />
+    </constructor>
+  </resultMap>
+
+  <!-- Map nested cursor to constructor arg (single). -->
+  <resultMap id="book2RM_ConstructorAssociation"
+    type="org.apache.ibatis.submitted.oracle_cursor.Book2">
+    <constructor>
+      <idArg column="id" javaType="int" />
+      <arg column="name" javaType="string" />
+      <arg column="author" jdbcType="CURSOR"
+        javaType="org.apache.ibatis.submitted.oracle_cursor.Author"
+        resultMap="authorRM_ConstructorIdName" />
+    </constructor>
+  </resultMap>
+
+  <select id="selectNestedCursorConstructorAssociation"
+    resultMap="book2RM_ConstructorAssociation">
+    <include refid="bookNestedCursor" />
+  </select>
+
 </mapper>