Hi, try to debug it a little. Please consider upgrading the build system to maven or something simillar, it will make things much easier to debug source code even for attached libraries.
I am unable to attach a patch; just copied & pasted it here, its single line of code + import:
class: at.bitfire.davdroid.webdav.DavHttpClient
action – register socket factory:
socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory> create() .register("https", TlsSniSocketFactory.INSTANCE) .register("http", PlainConnectionSocketFactory.getSocketFactory()) .build();Also consider printing full stacktraces from 3rd party libs.
EDIT: 1st time on GitHub – just created a pull request.