@Test
 public void servletOutputStreamCommittedWhenBufferSizeExceeded() throws IOException {
   assertFalse(response.isCommitted());
   response.getOutputStream().write('X');
   assertFalse(response.isCommitted());
   int size = response.getBufferSize();
   response.getOutputStream().write(new byte[size]);
   assertTrue(response.isCommitted());
   assertEquals(size + 1, response.getContentAsByteArray().length);
 }
 @Test
 public void servletWriterCommittedWhenBufferSizeExceeded() throws IOException {
   assertFalse(response.isCommitted());
   response.getWriter().write("X");
   assertFalse(response.isCommitted());
   int size = response.getBufferSize();
   char[] data = new char[size];
   Arrays.fill(data, 'p');
   response.getWriter().write(data);
   assertTrue(response.isCommitted());
   assertEquals(size + 1, response.getContentAsByteArray().length);
 }