We are using a custom implementation of the Address class in our JGroups setup. When combining this custom address format with JDBC_PING2, we encounter a data insertion error at runtime.

The error log is as follows:

JDBC_PING2.error:99]21:250529140510: failed writing to DB: java.sql.SQLIntegrityConstraintViolationException: Column 'address' cannot be null

The root cause appears to be in the following method in JDBC_PING2:

public static String addressToString(Address addr) {
    if (addr == null)
        return null;
    if (addr.isSiteAddress())

{ // SiteUUID         SiteUUID su = (SiteUUID) addr;         return String.format("%s%s:%s:%s", SITE_UUID_PREFIX, su.toStringLong(), su.getName(), su.getSite());     }

    Class<? extends Address> cl = addr.getClass();
    if (UUID.class.isAssignableFrom(cl)) // UUID, FlagsUUID, ExtendedUUID
        return String.format("%s%s", UUID_PREFIX, ((UUID) addr).toStringLong());
    if (IpAddress.class.equals(cl))
        return String.format("%s%s", IP_PREFIX, addr);
    return null;
}

Since our custom Address class does not fall into any of the known types (UUID, SiteUUID, or IpAddress), this method returns null. As a result, the address column in the database ends up being null, causing a SQL error