public Collection<ProtocolResolver> getProtocolResolvers() {
        return this.protocolResolvers;
    }
Return the collection of currently registered protocol resolvers,
allowing for introspection as well as modification.

see #addProtocolResolver(ProtocolResolver)
@since 4.3
analyzer/src/main/java/nl/basjes/parse/useragent/utils/springframework/core/io/DefaultResourceLoader.java