Pretty straight forward actually.
I "tiles
ut" an attribute as part of the insert in the "formBean1.jsp" and passed in the formbean name, say "FormBean1". Then I imported this attribute in the "commonTile.jsp" and used that as the bean to refer the tag properties to.
e.g.
------------------------
Code in formBean1.jsp:
<tiles:insert definition="testInsertTile">
<tiles
ut name="formBeanForCommonTile" beanName="FormBean1" />
</tiles:insert>
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Code in commonTile.jsp:
<tiles:importAttribute name="formBeanForCommonTile" />
<bean:write name="formBeanForCommonTile" property="anAttrInForm" />
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Worked out just fine.