@Override
      public Object call() throws Exception {
        getCache().getTxManager().addListener(new TestTxListener(true));
        Region<CustId, Customer> custRegion = getCache().getRegion(CUSTOMER);
        Context ctx = getCache().getJNDIContext();
        UserTransaction tx = (UserTransaction) ctx.lookup("java:/UserTransaction");
        assertThat(Status.STATUS_NO_TRANSACTION).isEqualTo(tx.getStatus());
        tx.begin();
        assertThat(Status.STATUS_ACTIVE).isEqualTo(tx.getStatus());
        custRegion.put(expectedCustId, expectedCustomer);
        assertThat(expectedCustomer).isEqualTo(custRegion.get(expectedCustId));
        return null;
      }
@return first key found on the given member
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/RemoteTransactionDUnitTest.java