@Test
  public void testMaxPoolSize() throws Exception {
    Host host = Host.getHost(0);
    VM vm0 = host.getVM(0);
    AsyncInvocation<Void> asyncObj = vm0.invokeAsync(MaxPoolSizeDUnitTest::runTest1);
    ThreadUtils.join(asyncObj, 30 * 1000);
    if (asyncObj.exceptionOccurred()) {
      Assert.fail("asyncObj failed", asyncObj.getException());
    }
  }
Return file as string and then modify the string accordingly **
geode-core/src/distributedTest/java/org/apache/geode/internal/jta/dunit/MaxPoolSizeDUnitTest.java