Using annotation-based Java EE Dependency Injection with selective override via ejb-jar.xml deployment descriptor with GlassFish 3.1.2.2 Files: * FooBean, which depends on a Bar * BarBean, which is the default implementation of a Bar * AlternativeBarBean is the Bar that should be used * ejb-jar.xml overrides the default Bar in FooBean with the A…

AlternativeBarBean.java

package com.acme;

/**
 * alternative implementation of Bar, provided by com.acme, will be packaged alongside org.sample
 *
 * mappedName is required here, see http://stackoverflow.com/questions/7443306/javaee-6-javax-naming-namealreadyboundexception-use-rebind-to-override
 */
@Stateless(mappedName = "AlternativeBarBean")
public class AlternativeBarBean implements Bar {
...
}

BarBean.java

package org.sample;

@Stateless
public class BarBean implements Bar {
...
}

ejb-jar.xml

<?xml version="1.0" encoding="UTF-8"?>
<!-- 
  this is the ejb-jar.xml of the com.acme package. It overrides a dependency defined in the org.sample package.
-->
<ejb-jar xmlns="http://java.sun.com/xml/ns/javaee" version="3.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/ejb-jar_3_0.xsd">
    <enterprise-beans>
        <!-- override FooBean's dependency on BarBean with AlternativeBarBean -->
        <session>
            <ejb-name>FooBean</ejb-name>
            <ejb-local-ref>
                <!-- this is the GlassFish generated JNDI name if no @EJB(name=...) is specified  -->
                <ejb-ref-name>org.sample.FooBean/bar</ejb-ref-name>
                <!-- use this alternative implementation instead -->
                <ejb-link>AlternativeBarBean</ejb-link>
            </ejb-local-ref>
        </session>
    </enterprise-beans>
</ejb-jar>

FooBean.java

package org.sample;

@Stateless
public class FooBean implements Foo {

	@EJB
	private Bar bar;
...
}