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6.3. XML definition

The JPA specification allows annotation overriding through JPA deployment descriptor. There is also an additional feature that can be useful: default event listeners. 
<?xml version="1.0" encoding="UTF-8"?>

<entity-mappings xmlns="http://java.sun.com/xml/ns/persistence/orm"
                 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:schemaLocation="http://java.sun.com/xml/ns/persistence/orm orm_1_0.xsd"
                 version="1.0"
        >
    <persistence-unit-metadata>
        <persistence-unit-defaults>
            <entity-listeners>
                <entity-listener class="org.hibernate.ejb.test.pack.defaultpar.IncrementListener">
                    <pre-persist method-name="increment"/>
                </entity-listener>
            </entity-listeners>
        </persistence-unit-defaults>
    </persistence-unit-metadata>
    <package>org.hibernate.ejb.test.pack.defaultpar</package>
    <entity class="ApplicationServer">
        <entity-listeners>
            <entity-listener class="OtherIncrementListener">
                <pre-persist method-name="increment"/>
            </entity-listener>
        </entity-listeners>


        <pre-persist method-name="calculate"/>
    </entity>
</entity-mappings>
You can override entity listeners on a given entity. An entity listener correspond to a given class and one or several event fire a given method call. You can also define event on the entity itself to describe the callbacks.
Last but not least, you can define some default entity listeners that will apply first on the entity listener stack of all the mapped entities of a given persistence unit. If you don't want an entity to inherit the default listeners, you can use @ExcludeDefaultListeners (or <exclude-default-listeners/>).