Specify default value in Hibernate's XML configuration file

Question

I'm configuring Hibernate via the mapping configuration file.

<class name="Person" table="person">
    <id name="id" column="id" type="long"/>
    <property name="name" column="name" type="string"/>
    <property name="age" column="age" type="integer"/>
</class>

How do I set age to be nullable and default to null?

Answer 1

<property name="age" type="integer">
  <column name="age" not-null="false" default="null" />
</property>