java - implementing one to many relationship encourage this exception: During synchronization a new object was found through a relationship -


i have 2 entity classes have 1 many relationship. suggestion , suggestionscope classes. (1 suggestion has 1 suggestion scope 1 suggestion scope used in many suggestion) want implement using jpa. implemented this:

public class suggestion {      @id     @sequencegenerator(name = "suggestion_sequence_generator", sequencename = "suggestion_seq", initialvalue = 1, allocationsize = 1)     @generatedvalue(strategy = generationtype.sequence, generator = "suggestion_sequence_generator")     @xmlelement(name = "id")     @column(name = "id", nullable = false)     private long id;       @manytoone( fetch = fetchtype.lazy)     @joincolumn(name = "fk_suggestion_scope")     @xmlelement(name = "fk_suggestion_scope")     private suggestionscope suggestionscope;      ...  }

this child side , in parent side have not used relational annotation, when try run it, exception:

java.lang.illegalstateexception: during synchronization new object found through relationship not marked cascade persist: suggestionscope{id=null, name='null'}.

i have added part child side: 

@manytoone( fetch = fetchtype.lazy,cascade = cascadetype.persist) @joincolumn(name = "fk_suggestion_scope") @xmlelement(name = "fk_suggestion_scope") private suggestionscope suggestionscope;

by time run it, 1 one relation!!; each record of child table persisting 1 parent also!

thanks in advance


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