PersistenceProviderTracker.java 文件源码

private static Filter createFilter(BundleContext context, PersistenceUnit punit) {
    String filter;
    if (punit.getPersistenceProviderClassName() != null) {
        filter = String.format("(&(objectClass=%s)(%s=%s))",
                               PersistenceProvider.class.getName(),
                               JAVAX_PERSISTENCE_PROVIDER,
                               punit.getPersistenceProviderClassName());
    } else {
        filter = String.format("(objectClass=%s)", PersistenceProvider.class.getName());
    }

    try {
        return context.createFilter(filter);
    } catch (InvalidSyntaxException e) {
        throw new IllegalArgumentException(e);
    }
}