If you hit oracle.security.jps.JpsRuntimeException: Cannot read from policy store.

When trying to start your integrated weblogic server, if you come across the following error :-

oracle.security.jps.JpsRuntimeException: Cannot read from policy store.
  at oracle.security.jps.internal.policystore.xml.XmlPolicyStore.buildFromFile(XmlPolicyStore.java:425)
 at oracle.security.jps.internal.policystore.xml.XmlPolicyStore.(XmlPolicyStore.java:224)
        ...
Caused by: oracle.security.jps.JpsRuntimeException: javax.xml.stream.XMLStreamException: End Document reached prematurely.
  at oracle.security.jps.internal.core.datastore.xml.XmlDataStoreParser.getDataStoreEntryStax
 (XmlDataStoreParser.java:166)
   ...
   ... 28 more
   ...
weblogic.security.SecurityInitializationException: The loading of OPSS java security policy provider failed due to exception, see the exception stack trace or the server log file for root cause. If still see no obvious cause, enable the debug flag -Djava.security.debug=jpspolicy to get more information. Error message: 

  oracle.security.jps.JpsException: [PolicyUtil] Exception while getting default policy Provider
       at weblogic.security.service.CommonSecurityServiceManagerDelegateImpl.loadOPSSPolicy
    (CommonSecurityServiceManagerDelegateImpl.java:1398)
        ...
Caused By: oracle.security.jps.JpsRuntimeException: oracle.security.jps.JpsException: [PolicyUtil] Exception while getting default policy Provider
           at oracle.security.jps.internal.policystore.PolicyDelegationController.(PolicyDelegationController.java:291)
...       
Caused By: java.security.PrivilegedActionException: oracle.security.jps.JpsException: [PolicyUtil] Unable to obtain default JPS Context!
     at java.security.AccessController.doPrivileged(Native Method)
...
Caused By: oracle.security.jps.JpsRuntimeException: Cannot read from policy store.
    at oracle.security.jps.internal.policystore.xml.XmlPolicyStore.buildFromFile(XmlPolicyStore.java:42

Solution:-

This issue mostly occurs due to a corruption in the jazn-data.xml file. You could delete the jazn-data.xml file under the DefaultDomain directory or delete the 'DefaultDomain' directory under the system directory inside your view. This will create the domain afresh the next time you start your WLS.