gradle and/or java errors installing the pipeline engine

[Alle Meije Wink]

To install the pipeline engine I downloaded and extracted the zip file, and then had to fill out some settings in a GRADLE file:

xnatUrl=http://oldschool.edu
siteName=XNAT
adminEmail=ad...@oldschool.edu
smtpServer=mail.oldschool.edu
destination=/data/xnat/pipeline

I guess that
  xnatUrl=145.121.54.181 (the address of the XNAT host)
  siteName is freeform (just XNAT for now?)
  adminEmail=tom...@145.121.54.181 (as that is the user who owns all the files)
  smtpServer=mail.oldschool.edu (not sure what to put here -- I installed Exim but no front end)
  destination=/data/xnat/pipeline (sounds right)
so that is what I put in

Then when I run ./gradlew as root, I get loads of Java errors, see below.

Just to make sure I have gradle installed on my computer (just `apt install gradle`)

I am not a great java crack so this means nothing to me...
If any of you know what this means (and how to solve this) then that would be greatly appreciated!




#######################
##### output of `gradle` #####
#######################




Downloading https://services.gradle.org/distributions/gradle-2.13-all.zip

Exception in thread "main" javax.net.ssl.SSLException: java.security.ProviderException: java.security.InvalidKeyException: EC parameters error
        at sun.security.ssl.Alerts.getSSLException(Alerts.java:208)
        at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1914)
        at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1872)
        at sun.security.ssl.SSLSocketImpl.handleException(SSLSocketImpl.java:1855)
        at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1376)
        at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1353)
        at sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:559)
        at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:185)
        at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1348)
        at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:254)
        at org.gradle.wrapper.Download.downloadInternal(Download.java:58)
        at org.gradle.wrapper.Download.download(Download.java:44)
        at org.gradle.wrapper.Install$1.call(Install.java:61)
        at org.gradle.wrapper.Install$1.call(Install.java:48)
        at org.gradle.wrapper.ExclusiveFileAccessManager.access(ExclusiveFileAccessManager.java:65)
        at org.gradle.wrapper.Install.createDist(Install.java:48)
        at org.gradle.wrapper.WrapperExecutor.execute(WrapperExecutor.java:128)
        at org.gradle.wrapper.GradleWrapperMain.main(GradleWrapperMain.java:61)
Caused by: java.security.ProviderException: java.security.InvalidKeyException: EC parameters error
        at sun.security.pkcs11.P11Key$P11ECPublicKey.getEncodedInternal(P11Key.java:1024)
        at sun.security.pkcs11.P11Key.equals(P11Key.java:158)
        at java.util.ArrayList.indexOf(ArrayList.java:298)
        at java.util.ArrayList.contains(ArrayList.java:281)
        at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:239)
        at sun.security.validator.Validator.validate(Validator.java:260)
        at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:326)
        at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:231)
        at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:126)
        at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1459)
        at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:213)
        at sun.security.ssl.Handshaker.processLoop(Handshaker.java:961)
        at sun.security.ssl.Handshaker.process_record(Handshaker.java:897)
        at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1033)
        at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1342)
        at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1369)
        ... 13 more
Caused by: java.security.InvalidKeyException: EC parameters error
        at sun.security.ec.ECParameters.getAlgorithmParameters(ECParameters.java:284)
        at sun.security.ec.ECPublicKeyImpl.<init>(ECPublicKeyImpl.java:59)
        at sun.security.pkcs11.P11Key$P11ECPublicKey.getEncodedInternal(P11Key.java:1021)
        ... 28 more
Caused by: java.security.NoSuchProviderException: no such provider: SunEC
        at sun.security.jca.GetInstance.getService(GetInstance.java:83)
        at sun.security.jca.GetInstance.getInstance(GetInstance.java:206)
        at java.security.Security.getImpl(Security.java:697)
        at java.security.AlgorithmParameters.getInstance(AlgorithmParameters.java:199)
        at sun.security.ec.ECParameters.getAlgorithmParameters(ECParameters.java:279)
        ... 30 more