hibernate - Storing structured comments in MYSQL database using Java JPA and Spring Data -


using spring data , java jpa, store comment threads in mysql table. comments on chunk of data, , every comment can have number of child comments (think reddit). wondering if java class makes sense fulfill needs.

@entity public class comment extends identified {      // comment data     @column(nullable=false)     private string data;      // parent comment     @manytoone(fetch=fetchtype.lazy)     @joincolumn(nullable=true)     private comment parent;      // sub comments     @onetomany(fetch=fetchtype.eager)     @joincolumn(nullable=true, mappedby="parent")     private set<comment> children;      public comment() { }     ....

to clarify, main concern regards having both manytoone , onetomany relationship same class. seems ugly, way express relationship.

i assure mapping normal, usual. 2 relationships (many-to-one , one-to-many) realized in db using different concepts , not collide. relationship bidirectional, both mappings represent different ends of 2 different links (one relation parent, relation child).


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