Coverity static-analysis scan found possible method call on null object in {{org.​wildfly.​security.​credential.​source.​CredentialStoreCredentialSource.​getCredential(java.​lang.​Class, java.​lang.​String, java.​security.​spec.​AlgorithmParameterSpec)}}

https://scan7.coverity.com/reports.htm#v16159/p11778/fileInstanceId=6803729&defectInstanceId=1776827&mergedDefectId=1388281&eventId=1776827-8
The problematic piece of code is:

credential = credentialStore.retrieve(alias, credentialType);
return credential.castAs(credentialType, algorithmName, parameterSpec);

The retrieve() method may return null in some cases as can be seen in KeyStoreCredentialStore class:

//...
final TopEntry topEntry = cache.get(credentialAlias);
if (topEntry == null) {
    return null;
}
//...