Distributed Computing Wikiclass | Tutorial / Using Java to access Flickr Web Services

Introduction

Flickr is a photo-sharing community that enables users to upload hundreds of photos and tag each photo with descriptive words. Other users can then search on these tags, enabling them to find and comment on the photos of other users. Flickr's active community and addictive sharing features have attracted millions of users. Even better, Flickr exposes a rich set of Web services that make the service highly hackable.

Go to the following websites to know more about Flickr service and Flickr API

Sending a service request to Flickr

String serviceEndpoint = "http://api.flickr.com/services/rest/?method=flickr.photos.search&api_key=24d52be90f046c1d2f05bbd2f47d40b6&per_page=5&text=apple";

URLConnection uc = new URL(serviceEndpoint).openConnection();

DataInputStream dis = new DataInputStream(uc.getInputStream());

FileWriter fileWriter = new FileWriter(new File("D:\\response.xml"));

String nextline;

String[] servers = new String[10];

String[] ids = new String[10];

String[] secrets = new String[10];

while ((nextline = dis.readLine()) != null) {

  fileWriter.append(nextline);

}

dis.close();

filewriter.close();

[Get Code]

Parsing the XML file to get the image URL

String filename = "D:\\response.xml";

XMLInputFactory factory = XMLInputFactory.newInstance();

System.out.println("FACTORY: " + factory);

XMLEventReader r = factory.createXMLEventReader(filename, new FileInputStream(filename));

int i = -1;

while (r.hasNext()) {

  XMLEvent event = r.nextEvent();

  if (event.isStartElement()) {

    StartElement element = (StartElement) event;

    String elementName = element.getName().toString();

    if (elementName.equals("photo")) {

      i++;

      Iterator iterator = element.getAttributes();

      while (iterator.hasNext()) {

        Attribute attribute = (Attribute) iterator.next();

        QName name = attribute.getName();

        String value = attribute.getValue();

        System.out.println("Attribute name/value: " + name + "/" + value);

        if ((name.toString()).equals("server")) {

          servers[i] = value;

          System.out.println("Server Value" + servers[0]);

        }

        if ((name.toString()).equals("id")) {

          ids[i] = value;

        }

        if ((name.toString()).equals("secret")) {

          secrets[i] = value;

        }

      }

      System.out.println(i);

      String flickrurl = "http://static.flickr.com/" + servers[i] + "/" + ids[i] + "_" + secrets[i] + ".jpg";

      System.out.println(flickrurl);

    }

  }

}

[Get Code]

The XML API you may need to import

import javax.xml.namespace.QName;

import javax.xml.stream.XMLEventReader;

import javax.xml.stream.XMLInputFactory;

import javax.xml.stream.events.Attribute;

import javax.xml.stream.events.StartElement;

import javax.xml.stream.events.XMLEvent;

[Get Code]

Your task

Write a simple Java program to demonstrate the working of the code segments.

Write more code to enhance the features of your program.

Using Java to access Flickr Web Services

Introduction

Sending a service request to Flickr

Parsing the XML file to get the image URL

The XML API you may need to import

Your task

Resources for you to probe further