This is a very basic problem, and I have tried many combination but it is not
working at all.
I have two table , let assume, there is 1-1 relationship for simplification of
problem at hand
Teacher(id, name)
Student(id,name,teacher_id)
The two beans are
public class Teacher {
private Integer id;
private String name;
private Integer student_Id;
......
}
public class Student {
private Integer id;
private String name;
private Integer teacher_id;
......
}
SQL config MAp is
<resultMap id="TeacherResultMap" class="Teacher">
<result property="id" column="id"/>
<result property="name" column="name"/>
<result property="student_id" column="id" select="findStudentByTeacherId"/>
</resultMap>
<select id="findStudentByTeacherId" resultClass="int">
select id from Student where id = #value#
</select>
<select id="findTeacherById" resultMap="TeacherResultMap">
select id , name from Teacher where id = #value#
</select>
My Test code calls
queryForObject("findTeacherById", id);
But I get the following exception
Caused by: com.ibatis.common.jdbc.exception.NestedSQLException:
--- The error occurred in maps/JOB_SqlMap.xml.
--- The error occurred while applying a result map.
--- Check the JOB.TeacherResultMap.
--- Check the result mapping for the 'student_id' property.
--- Cause: java.lang.NullPointerException
at
com.ibatis.sqlmap.engine.mapping.statement.MappedStatement.executeQueryWithCallback(MappedStatement.java:204)
at
com.ibatis.sqlmap.engine.mapping.statement.MappedStatement.executeQueryForObject(MappedStatement.java:120)
at
com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForObject(SqlMapExecutorDelegate.java:518)
at
com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForObject(SqlMapExecutorDelegate.java:493)
at
com.ibatis.sqlmap.engine.impl.SqlMapSessionImpl.queryForObject(SqlMapSessionImpl.java:106)
at
org.springframework.orm.ibatis.SqlMapClientTemplate$1.doInSqlMapClient(SqlMapClientTemplate.java:273)
at
org.springframework.orm.ibatis.SqlMapClientTemplate.execute(SqlMapClientTemplate.java:209)
... 27 more
Caused by: java.lang.NullPointerException
at
com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.endTransaction(SqlMapExecutorDelegate.java:734)
at
com.ibatis.sqlmap.engine.impl.SqlMapSessionImpl.endTransaction(SqlMapSessionImpl.java:176)
at
com.ibatis.sqlmap.engine.impl.SqlMapClientImpl.endTransaction(SqlMapClientImpl.java:153)
at
com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.autoEndTransaction(SqlMapExecutorDelegate.java:835)
at
com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForObject(SqlMapExecutorDelegate.java:525)
at
com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForObject(SqlMapExecutorDelegate.java:493)
at
com.ibatis.sqlmap.engine.impl.SqlMapSessionImpl.queryForObject(SqlMapSessionImpl.java:106)
at
com.ibatis.sqlmap.engine.impl.SqlMapClientImpl.queryForObject(SqlMapClientImpl.java:82)
at
com.ibatis.sqlmap.engine.mapping.result.loader.ResultLoader.getResult(ResultLoader.java:75)
at
com.ibatis.sqlmap.engine.mapping.result.loader.ResultLoader.loadResult(ResultLoader.java:57)
at
com.ibatis.sqlmap.engine.mapping.result.ResultMap.getNestedSelectMappingValue(ResultMap.java:510)
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.sqlExecuteQuery(MappedStatement.java:221)
at
com.ibatis.sqlmap.engine.mapping.statement.MappedStatement.executeQueryWithCallback(MappedStatement.java:189)
... 33 more
