### Question:
WebDavMessage extends MimeMessage { public void setNewHeaders(ParsedMessageEnvelope envelope) throws MessagingException { String[] headers = envelope.getHeaderList(); Map<String, String> messageHeaders = envelope.getMessageHeaders(); for (String header : headers) { String headerValue = messageHeaders.get(header); if (header.equals("Content-Length")) { int size = Integer.parseInt(headerValue); this.setSize(size); } if (headerValue != null && !headerValue.equals("")) { this.addHeader(header, headerValue); } } } WebDavMessage(String uid, Folder folder); void setUrl(String url); String getUrl(); void setSize(int size); void setFlagInternal(Flag flag, boolean set); void setNewHeaders(ParsedMessageEnvelope envelope); @Override void delete(String trashFolderName); @Override void setFlag(Flag flag, boolean set);  }### Answer:
@Test public void setNewHeaders_updates_size() throws MessagingException { ParsedMessageEnvelope parsedMessageEnvelope = new ParsedMessageEnvelope(); parsedMessageEnvelope.addHeader("getcontentlength", "1024"); message.setNewHeaders(parsedMessageEnvelope); assertEquals(1024, message.getSize()); }