weld/subsystem/src/main/java/org/jboss/as/weld/deployment/processors/ExternalBeanArchiveProcessor.java
private Map<URL, URL> findExportedResources(Module dependencyModule) {
        Set<URL> beanXmls = findExportedResource(dependencyModule, META_INF_BEANS_XML);
        if (beanXmls.isEmpty()) {
            return Collections.emptyMap();
        }
        Set<URL> indexes = findExportedResource(dependencyModule, META_INF_JANDEX_IDX);
        Map<URL, URL> ret = new HashMap<>();
        for (URL beansXml : beanXmls) {
            String urlBase = beansXml.toString().substring(0, beansXml.toString().length() - META_INF_BEANS_XML.length());
            URL idx = null;
            for (URL index : indexes) {
                if (index.toString().startsWith(urlBase)) {
                    idx = index;
                    break;
                }
            }
            ret.put(beansXml, idx);
        }
        return ret;
    }
private Map<URL, URL> findExportedResources(Module dependencyModule) {
        Set<URL> beanXmls = findExportedResource(dependencyModule, META_INF_BEANS_XML);
        if (beanXmls.isEmpty()) {
            return Collections.emptyMap();
        }
        Set<URL> indexes = findExportedResource(dependencyModule, META_INF_JANDEX_IDX);
        Map<URL, URL> ret = new HashMap<>();
        for (URL beansXml : beanXmls) {
            String urlBase = beansXml.toString().substring(0, beansXml.toString().length() - META_INF_BEANS_XML.length());
            URL idx = null;
            for (URL index : indexes) {
                if (index.toString().startsWith(urlBase)) {
                    idx = index;
                    break;
                }
            }
            ret.put(beansXml, idx);
        }
        return ret;
    }
The entry key is bean.xml URL, value is (optional) jandex index URL.

@param dependencyModule
@return the map of exported resources