Testing what's written to a Java OutputStream

Question

I am about to write junit tests for a XML parsing Java class that outputs directly to an OutputStream. For example xmlWriter.writeString(\"foo\"); would produce

Answer 1

It's simple. As @JonSkeet said:

ByteArrayOutputStream baos = new ByteArrayOutputStream();
// pass the baos to be writed with "value", for this example
byte[] byteArray = baos.toByteArray();
Assert.assertEquals("value", new String(byteArray));