Can I make an embedded Hibernate entity non-nullable?

Add dummy field into class which is marked @Embeddable.

@Formula("0")
private int dummy;

See https://issues.jboss.org/browse/HIBERNATE-50 .

I wasn't too thrilled with either of the suggestions previously made, so I created an aspect that would handle this for me.

This isn't fully tested, and definitely not tested against Collections of embedded objects, so buyer-beware. However, seems to work for me so far.

Basically, intercepts the getter to the @Embedded field and ensures that the field is populated.

public aspect NonNullEmbedded {

    // define a pointcut for any getter method of a field with @Embedded of type Validity with any name in com.ia.domain package
    pointcut embeddedGetter() : get( @javax.persistence.Embedded * com.company.model..* );


    /**
     * Advice to run before any Embedded getter.
     * Checks if the field is null.  If it is, then it automatically instantiates the Embedded object.
     */
    Object around() : embeddedGetter(){
        Object value = proceed();

        // check if null.  If so, then instantiate the object and assign it to the model.
        // Otherwise just return the value retrieved.
        if( value == null ){
            String fieldName = thisJoinPoint.getSignature().getName();
            Object obj = thisJoinPoint.getThis();

            // check to see if the obj has the field already defined or is null
            try{
                Field field = obj.getClass().getDeclaredField(fieldName);
                Class clazz = field.getType();
                value = clazz.newInstance();
                field.setAccessible(true);
                field.set(obj, value );
            }
            catch( NoSuchFieldException | IllegalAccessException | InstantiationException e){
                e.printStackTrace();
            }
        }

        return value;
    }
}

You can use a nullsafe getter.

public Direito getDireito() {
    if (direito == null) {
        direito = new Direito();
    }
    return direito;
}