private String getOutString() {
            return outString;
        }
This tests to make sure that BatchProcess waits the appropriate
amount of time on an early termination before stopping.
<p>
If this fails, then interruptible parsers (e.g. those with
nio channels) will be interrupted and there will be corrupted data.
tika-batch/src/test/java/org/apache/tika/batch/fs/BatchProcessTest.java