docs: private static boolean checkUserPassword(String userSecurityName, String password, UserRegistry registry, String realmName, Hashtable<String, Object> addedCred,
                                               Invocation isCCInvoked) { // 675924
  
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) {
              Tr.entry(tc, "checkUserPassword user: " + userSecurityName + ", realm: " + realmName);
          }
          if (userSecurityName == null || password == null) {
              Tr.error(tc, "INVALID_USERNAME_PASSWORD_INBOUND_J2CA0674", userSecurityName); // 673415
              if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) {
                  Tr.exit(tc, "checkUserPassword", new Object[] { userSecurityName, password });
              }
              return false; // 675924
          }
          boolean match = validateCallbackInformation(addedCred, userSecurityName, isCCInvoked); // 675924
          if (!match) {
              if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) {
                  Tr.exit(tc, "checkUserPassword", " - invalid username and password.");
              }
              return false; // 675924
          }
          try {
              registry.checkPassword(userSecurityName, password);
              String uniqueId = registry.getUniqueUserId(userSecurityName);
              uniqueId = stripRealm(uniqueId, realmName); // 669627
              List<String> uniqueGroups = new ArrayList<String>();
              List<?> groupNames = registry.getGroupsForUser(userSecurityName);
              if (groupNames != null)
                  for (Object group : groupNames) {
                      uniqueGroups.add(registry.getUniqueGroupId((String) group));
                  }
              updateCustomHashtable(addedCred, realmName, uniqueId, userSecurityName, uniqueGroups);
          } catch (PasswordCheckFailedException e) {
              // This error is thrown when there is no entry corresponding to the username and password
              // in the registry.
              Tr.error(tc, "INVALID_USERNAME_PASSWORD_INBOUND_J2CA0674", userSecurityName);
              if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) {
                  Tr.exit(tc, "checkUserPassword", " - invalid username and password"); // 675924 
              }
              return false; // 675924 
          } catch (Exception e) {
              FFDCFilter.processException(e, "com.ibm.ejs.j2c.work.security.J2CSecurityHelper.checkUserPassword", "%C");
              Tr.error(tc, "VALIDATION_FAILED_INBOUND_J2CA0684", userSecurityName); // 675924
              if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) {
                  Tr.exit(tc, "checkUserPassword", " - unable to validate password.");
              }
              return false; // 675924
          } // End 673415
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) {
              Tr.exit(tc, "checkUserPassword", " - password is valid.");
          }
          return true;
      }