one-to-one annotation in a POJO:

one-to-one element in a Hibernate mapping file:

If you have a set of Java classes which are interdependent on each other, you could use the "Add Hibernate/JPA Annotations..." action to automatically detect relationships which exist between these POJOs and add corresponding annotations to the classes.
In a Hibernate, JPA or EJB3 project, select the classes/containers you would like to analyze and then "Add Hibernate/JPA Annotations..." from the MyEclipse context menu.

Annotations can be added either to getters or fields in the Java classes:

Use the Preview to preview changes before applying them:

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