How to avoid LazyInitializationException when using ManyToMany as value for primefaces selectCheckboxMenu

The idea is to let the component know the type of data source collection.Sample code:<p:selectCheckboxMenu value="#{obj.students}" filter="true" filterMatchMode="startsWith"> <f:attribute name="collectionType" value="java.util.ArrayList" /> <f:selectItems value="#{elements}" var="elem"...