Has anyone noticed = this bug? I can’t believe that no one has stumbled upon = this.

Dragan

From:= Dragan = Jotanovic [mailto:Dragan.Jotanovic@DIOSPHERE.com]
Sent: Thursday, July 17, 2008 2:12 PM
To: user-java@ibatis.apache.org
Subject: Bug with complex property in result = map?

Hi there,

I noticed that after upgrading to newer version of = iBatis, some of the functionality that used to work with iBatis 2.0.9 stopped = working.

Namely, the problem occurred in case when there is = complex property in result map.

Here is the simple test case:

- Sql map:

</resultMap>

</resultMap>

select * from = TABLE_B

</select>

select * from = TABLE_A

where = id=3D#value#

</select>

- class A(id, description); class B (id, a_id, = object A)

- TABLE_A(id, description){(1, ‘rec 1’), (2, ‘rec 2’)}

- TABLE_B(id, a_id){(1, 1), (1, null)}

As you can see, a_id field in TABLE_B is nullable. =

When you invoke = queryForList(“getAllB”), iBatis breaks with following exception:

com.ibatis.common.jdbc.exception.NestedSQLException:

--- The error occurred in = Test.xml.

--- The error occurred while = applying a result map.

--- Check the Test.resultB. =

--- Check the result mapping for = the 'a' property.

--- Cause: java.lang.NullPointerException

at com.ibatis.sqlmap.engine.mapping.statement.MappedStatement.executeQueryWi= thCallback(MappedStatement.java:204)

at com.ibatis.sqlmap.engine.mapping.statement.MappedStatement.executeQueryFo= rList(MappedStatement.java:139)

at com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForList(= SqlMapExecutorDelegate.java:567)

at com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForList(= SqlMapExecutorDelegate.java:541)

at com.ibatis.sqlmap.engine.impl.SqlMapSessionImpl.queryForList(SqlMapSessionImpl.java:118)

at com.ibatis.sqlmap.engine.impl.SqlMapClientImpl.queryForList(SqlMapClientImpl.java:94)

at TestIbatis.main(TestIbatis.java:28)

Caused by: java.lang.NullPointerException

at java.lang.Class.isAssignableFrom(Native Method)

at com.ibatis.sqlmap.engine.type.TypeHandlerFactory.getTypeHandler(TypeHandlerFactory.java:143)

at com.ibatis.sqlmap.engine.type.TypeHandlerFactory.getTypeHandler(TypeHandlerFactory.java:123)

at com.ibatis.sqlmap.engine.mapping.result.ResultMap.prepareBeanParameterObj= ect(ResultMap.java:591)

at com.ibatis.sqlmap.engine.mapping.result.ResultMap.getNestedSelectMappingV= alue(ResultMap.java:475)

at com.ibatis.sqlmap.engine.mapping.result.ResultMap.getResults(ResultMap.java:341)

at com.ibatis.sqlmap.engine.execution.SqlExecutor.handleResults(SqlExecutor.java:384)

at com.ibatis.sqlmap.engine.execution.SqlExecutor.handleMultipleResults(SqlExecutor.java:300)

at com.ibatis.sqlmap.engine.execution.SqlExecutor.executeQuery(SqlExecutor.java:189)

at com.ibatis.sqlmap.engine.mapping.statement.MappedStatement.sqlExecuteQuer= y(MappedStatement.java:221)

at com.ibatis.sqlmap.engine.mapping.statement.MappedStatement.executeQueryWi= thCallback(MappedStatement.java:189)

... 6 = more

What I would expect is that for those null values in database, value of = property A in class B to be set to = null.

This used to work in version 2.0.9, and was broken after version 2.2 I think. = I tried with latest 2.3.3 as well with the same = result.

Is this a known issue, or maybe a feature? Is there some simple workaround = for the problem? I am aware that above solution is not perfect (problem of N+1 selects), but we already implemented a lot of queries this way and it = would be time consuming to rewrite them all.

Dragan