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OrderBy (Java EE 5 SDK) - Java Platform, Enterprise Edition v5.0 API Specifications

Java EE 5 SDK

javax.persistence
Annotation Type OrderBy


@Target(value={METHOD,FIELD})
@Retention(value=RUNTIME)
public @interface OrderBy

This annotation specifies the ordering of the elements of a collection valued association at the point when the association is retrieved.

The syntax of the value ordering element is an orderby_list, as follows:

    orderby_list::= orderby_item [,orderby_item]*
    orderby_item::= property_or_field_name [ASC | DESC]
 

If ASC or DESC is not specified, ASC (ascending order) is assumed.

If the ordering element is not specified, ordering by the primary key of the associated entity is assumed.

The property or field name must correspond to that of a persistent property or field of the associated class. The properties or fields used in the ordering must correspond to columns for which comparison operators are supported.

    Example:
    
    @Entity public class Course {
     ...
     @ManyToMany
     @OrderBy("lastname ASC")
     public List getStudents() {...};
     ...
    }
    
    @Entity public class Student {
      ...
      @ManyToMany(mappedBy="students")
      @OrderBy // PK is assumed
      public List getCourses() {...};
      ...
    }
 

Since:
Java Persistence 1.0

Optional Element Summary
 String value
          An orderby_list, specified as follows: orderby_list::= orderby_item [,orderby_item]* orderby_item::= property_or_field_name [ASC | DESC] If ASC or DESC is not specified, ASC (ascending order) is assumed.
 

value

public abstract String value
An orderby_list, specified as follows:
    orderby_list::= orderby_item [,orderby_item]*
    orderby_item::= property_or_field_name [ASC | DESC]
 

If ASC or DESC is not specified, ASC (ascending order) is assumed.

If the ordering element is not specified, ordering by the primary key of the associated entity is assumed.

Default:
""

Java EE 5 SDK

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