@Test
	public void testReadBigDecimalInvalid() {
		int index = 0;

		try {
			tuple.getBigDecimal(index);
			fail("field value is not a number, exception expected");
		}
		// TODO - in batch this used to be IllegalArgumentException (which is the nested exception type now)
		catch (ConversionFailedException e) {
			assertTrue(e.getMessage().indexOf("TestString") > 0);
		}

	}
This is a port of the FieldSet tests from Spring Batch
spring-xd-tuple/src/test/java/org/springframework/xd/tuple/DefaultTupleTestForBatch.java