Thread: Sending XML to PHP Service via POST

I have a server with a handful of php services. I communicate with these services by creating connections from java code. The services currently respond with XML, but that can be changed if an alternative way can improve performance.
One of the things I need to do is send varying sized payload (some large) to one of the services. My current plan is to create an xml file in java and perform a POST request with the XML as the payload. I am using an XML because the data is very structured.

From a performance point of view, would it be better to send the XML as a file or just as text?
Also, is there a better way to send this data? These services will eventually be used by an android app, where performance and minimizing the size of the data packages will be extremely important.

I'll have to look into that. I've used JSON at work before, but never on my personal time.
One of my services returned a 128kb (I think) XML result to my android app, and it took 10 minutes or so until the app just gave up (timeout or something I think). It was reading the XML, but EXTREMELY slowly. I was just using the standard DOM parser, so that probably didn't help expedite things. It was also an emulator instead of a real phone. Still, insanely slow. I was running it on another task, so nothing was locked up.

Well it only takes that long when attempting to do it from the Android emulator. I have an android platform and a desktop platform. The two call the exact same code, which performs the request to the service, deserializes, and loads the data into the same data structures. Nothing is different between the two. Except that the Android platform takes forever, while the desktop platform is milliseconds. It's on my to-do list to do some research into what Android is actually doing differently when it parses xml.

No. It is still compiled in Java SE 7 and the runtime is still Java SE 7. It shouldn't have any Java 8 stuff.
I use a DocumentBuilder created by the DocumentBuilderFactor (which I have set to be an instance of com.sun.org.apache.xerces.internal.jaxp.DocumentBu ilderFactoryImpl).
It parses the URL with the InputStream provided by the openStream() method (URL (Java Platform SE 7 )). That parses the info into org.w3c.dom objects.

/**
	 * Returns a Document from the give URL
	 * @param xml The url which contains the xml
	 * @return A document of the URL
	 * @throws ParserConfigurationException if the {@link DocumentBuilderFactory} implementation is not available or cannot be instantiated
	 * @throws IOException if an I/O exception occurs
	 * @throws SAXException if any parse errors occur
	 */
	public static Document loadXMLFromURL(URL xml) throws ParserConfigurationException, IOException, SAXException {
		System.setProperty("javax.xml.parsers.DocumentBuilderFactory", "com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderFactoryImpl"); 
		DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
 
	    factory.setNamespaceAware(true);
	    DocumentBuilder builder = factory.newDocumentBuilder();
	    return builder.parse(xml.openStream());
	}

The bottle neck appears to be continuous as it reads elements, not just an initial load thing.
I need to do more testing before I can figure out a proper cause.