java - iBATIS - Defining 'javaType' and 'jdbcType' -

while defining resultmap in ibatis, provides option set javatype , jdbctype each property column mapping.

e.g.

<resultmap id="employee" class="com.mycompany.employee">    <result property="firstname" column="first_name" javatype="?" jdbctype="?"/> </resultmap> 

wanted know when should defining javatype , jdbctype? have seen mapping just works without defining these properties , in others have define them.

edit: see selected answer below above question.

also, have exhaustive list out of javatype , jdbctype should defined?

edit: javatype should 1 of well-known types e.g. java.lang.string, java.util.date , jdbctype should coming out of java.sql.types

thanks in advance!

for jdbctype documentation (for ibatis 3) states:

the jdbc type required nullable columns upon insert, update or delete.

on page 33 in document list of supported jdbc types.

for javatype attribute says:

ibatis can figure out type if you’re mapping javabean. however, if mapping hashmap, should specify javatype explicitly ensure desired behaviour.