private static void ensureConnectionProvider() {
        if (connectionProvider != null) return;
        
        synchronized (providerLock) {
            if (connectionProvider != null) return;
            
            // Attempt to load the connection provider classname as a Jive property.
            String className = JiveGlobals.getXMLProperty("connectionProvider.className");
            if (className != null) {
                // Attempt to load the class.
                try {
                    Class conClass = ClassUtils.forName(className);
                    setConnectionProvider((ConnectionProvider)conClass.newInstance());
                } catch (Exception e) {
                    Log.warn("Failed to create the " +
                            "connection provider specified by connection" +
                            "Provider.className. Using the default pool.", e);
                    setConnectionProvider(new DefaultConnectionProvider());
                }
            } else {
                setConnectionProvider(new DefaultConnectionProvider());
            }
        }
    }
Ensures that the connection provider exists and is set
xmppserver/src/main/java/org/jivesoftware/database/DbConnectionManager.java