java - Error when connecting to URL - PKIX path building failed -

i trying connect webpage gather information, , using jsoup parse html. however, whenever try connect url download source, error saying pkix build path. i've looked around, , i've found says add website's ca root certificate truststore, did, problem persists (the ca root cert there). able connect website through web browser, not through url class. here basic code write produce error.

public class urlconnectstart {     public static void main(string[] args) {         try {             url u = new url("https://ntst.umd.edu/soc/");             u.openstream();              } catch (malformedurlexception e) {             e.printstacktrace();         } catch (ioexception e) {             e.printstacktrace();         }     } } 

here error

javax.net.ssl.sslhandshakeexception: sun.security.validator.validatorexception: pkix path building failed: sun.security.provider.certpath.suncertpathbuilderexception: unable find valid certification path requested target     @ sun.security.ssl.alerts.getsslexception(unknown source)     @ sun.security.ssl.sslsocketimpl.fatal(unknown source)     @ sun.security.ssl.handshaker.fatalse(unknown source)     @ sun.security.ssl.handshaker.fatalse(unknown source)     @ sun.security.ssl.clienthandshaker.servercertificate(unknown source)     @ sun.security.ssl.clienthandshaker.processmessage(unknown source)     @ sun.security.ssl.handshaker.processloop(unknown source)     @ sun.security.ssl.handshaker.process_record(unknown source)     @ sun.security.ssl.sslsocketimpl.readrecord(unknown source)     @ sun.security.ssl.sslsocketimpl.performinitialhandshake(unknown source)     @ sun.security.ssl.sslsocketimpl.starthandshake(unknown source)     @ sun.security.ssl.sslsocketimpl.starthandshake(unknown source)     @ sun.net.www.protocol.https.httpsclient.afterconnect(unknown source)     @ sun.net.www.protocol.https.abstractdelegatehttpsurlconnection.connect(unknown source)     @ sun.net.www.protocol.http.httpurlconnection.getinputstream0(unknown source)     @ sun.net.www.protocol.http.httpurlconnection.getinputstream(unknown source)     @ sun.net.www.protocol.https.httpsurlconnectionimpl.getinputstream(unknown source)     @ java.net.url.openstream(unknown source)     @ urlconnectstart.run(urlconnectstart.java:14)     @ urlconnectstart.main(urlconnectstart.java:8) caused by: sun.security.validator.validatorexception: pkix path building failed: sun.security.provider.certpath.suncertpathbuilderexception: unable find valid certification path requested target     @ sun.security.validator.pkixvalidator.dobuild(unknown source)     @ sun.security.validator.pkixvalidator.enginevalidate(unknown source)     @ sun.security.validator.validator.validate(unknown source)     @ sun.security.ssl.x509trustmanagerimpl.validate(unknown source)     @ sun.security.ssl.x509trustmanagerimpl.checktrusted(unknown source)     @ sun.security.ssl.x509trustmanagerimpl.checkservertrusted(unknown source)     ... 16 more caused by: sun.security.provider.certpath.suncertpathbuilderexception: unable find valid certification path requested target     @ sun.security.provider.certpath.suncertpathbuilder.build(unknown source)     @ sun.security.provider.certpath.suncertpathbuilder.enginebuild(unknown source)     @ java.security.cert.certpathbuilder.build(unknown source)     ... 22 more 

info chrome regarding website's cert

any appreciated. not critical application, security not important, if can maintain security rather so. regardless, want able download html website through code.

thank you.

the website does not provide intermediate certificate required complete certificate chain. user agents/ browsers have functionality called aia chasing download necessary intermediates java client isn't 1 of them.

if site admin, correct way address supply intermediate certificate complete chain sent. if end user, consider contacting website fix issue. folks using android browsers unable access site without accepting security warning due issue.

in meantime, if you'd address in client, can download missing intermediate cert , add java certificate store.