# @ejbgen:cmr-field Annotation

In a CMP entity bean, marks a container-managed relationship field. The entity relation that uses this CMR field is described in an @ejbgen:relation tag.

## Scope

Method tag for a CMP entity bean.

## Syntax

@ejbgen:cmr-field

[exclude-from-value-object="True/False"]

[group-names="GroupName"]

[ordering-number="0...N"]

[read-only-in-value-object="True/False"]

## Attributes

exclude-from-value-object

Optional. Specify True if you don't want this field to be included in the auo-generated value object (data transfer object) class. When left unspecified, this attribute defaults to false. For more information, see @ejbgen:file-generation Annotation.

group-names

Optional. This attribute defines how CMR fields of an entity bean are stored in memory. CMP fields and CMR fields that have the same group-name attribute specified are stored together. When this property is not used, all CMP fields and CMR fields are stored together in memory. Breaking up the memory signature into two or more groups can improve performance. For more details, see Accelerating Entity Bean Data Access.

ordering-number

Optional. Specify a number to enforce where this field will appear relative to other fields in signatures and constructors of generated compound primary key and value object (data transfer object) classes. In order for this ordering to work, all CMR and CMP fields must have this attribute set with a distinct numeric value.

read-only-in-value-object

Optional. Specify True if you want this field to be read-only in a generated value object class.

## Remarks

For more information on these attributes, see the identical attributes for @ejbgen:cmp-field Annotation. For more information on entity relations, see the @ejbgen:relation Annotation.

Related Topics

How Do I: Add a Relation to an Entity Bean?

Accelerating Entity Bean Data Access

@ejbgen:cmp-field Annotation

@ejbgen:entity Annotation

@ejbgen:file-generation Annotation

@ejbgen:relation Annotation