code: private void initializeConnectionProperties() throws ResourceException {
          try {
              // Retrieve the default values for all Connection properties. 
              // Save the default values for when null is specified in the CRI. 
  
              // - get the default values from the JDBC driver
              if (rrsTransactional) 
              { 
                  currentAutoCommit = defaultAutoCommit = true; 
                  if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled()) 
                  { 
                      Tr.debug(this, tc, "MCF is rrsTransactional:  forcing currentAutoCommit and defaultAutoCommit to true"); 
                  } 
              } 
              else 
              { 
                  currentAutoCommit = defaultAutoCommit = sqlConn.getAutoCommit();
                  if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled()) 
                  { 
                      Tr.debug(this, tc, "MCF is NOT rrsTransactional:  setting currentAutoCommit and defaultAutoCommit to " + defaultAutoCommit + " from underlying Connection"); 
                  } 
              } 
              defaultCatalog = sqlConn.getCatalog();
              defaultReadOnly = mcf.supportsIsReadOnly ? sqlConn.isReadOnly() : false;
              defaultTypeMap = getTypeMapSafely();
              currentShardingKey = initialShardingKey = cri.ivShardingKey;
              currentSuperShardingKey = initialSuperShardingKey = cri.ivSuperShardingKey;
              currentSchema = defaultSchema = getSchemaSafely();
              currentNetworkTimeout = defaultNetworkTimeout = getNetworkTimeoutSafely();
              currentHoldability = defaultHoldability; 
  
              currentTransactionIsolation = sqlConn.getTransactionIsolation(); 
  
          } catch (SQLException sqlX) {
              FFDCFilter.processException(sqlX,
                                          getClass().getName() + ".initializeConnectionProperties", "381", this);
              throw new DataStoreAdapterException("DSA_ERROR", sqlX, getClass());
          }
      }
docs: Initialize all Connection properties for the ManagedConnection. The current values (and
  previous values if applicable) should be retrieved from the underlying connection.
  Requested values and initially requested values should be taken from the
  ConnectionRequestInfo.
  
  @throws ResourceException if an error occurs retrieving default values.