Solved

How to fetch  live data from website ?

Posted on 2012-03-22
7
687 Views
Last Modified: 2012-03-24
How to  fetch  live data from website  ( without RSS feed / Webservice )?  

Do you  use any API ?

Example:  Live cricket scores


I want to write a standalone java program which will fetch  live data from  site. How do I start ?  What are the things I require ?

Could you throw some light .
0
Comment
Question by:cofactor
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
7 Comments
 
LVL 30

Expert Comment

by:IanTh
ID: 37751683
you need a database so the web site works and you can view the data remotely

Do you use any api

that depends on your setup I expect it will be linux and you can install mysql its usually installed anyway although it can be installed in windows

for remote view
see
http://www.softpedia.com/get/Internet/Servers/Database-Utils/Remote-MySQL-Viewer.shtml
0
 
LVL 40

Accepted Solution

by:
gurvinder372 earned 500 total points
ID: 37751860
you can invoke that URL using HTTPURLConnection
http://docs.oracle.com/javase/tutorial/networking/urls/readingWriting.html

once you have got the content of that URL, then you can parse it using Xpath
http://www.rgagnon.com/javadetails/java-0550.html
http://htmlparser.sourceforge.net/
0
 
LVL 40

Expert Comment

by:gurvinder372
ID: 37751864
you may have to use jTidy to purify HTML
http://jtidy.sourceforge.net/
0
Certified OpenStack Administrator Course

We just refreshed our COA course based on the Newton exam.  With 14 labs, this course goes over the different OpenStack services that are part of the certification: Dashboard, Identity Service, Image Service, Networking, Compute, Object Storage, Block Storage, and Orchestration.

 

Author Comment

by:cofactor
ID: 37752007
@gurvinder372
>>>you can invoke that URL using HTTPURLConnection

Is not that involve a  loop ?  something like this ...

while(true)
{
//HTTPURLConnection ...get data from site
//parse and get  required data
  Thread.sleep(30 secs)
}


OR   there  is some other smart and better approach exists I'm missing here ?


I  know a good package which  is capable of doing this kind of work neatly.  
http://httpunit.sourceforge.net/doc/faq.html

But I'm not sure whether you'll be using a loop to hit server every 30 secs interval to fetch latest updates  or  there is  better  a way ?


Please post you  comments
0
 
LVL 40

Expert Comment

by:gurvinder372
ID: 37752211
smarter approach would be to use web-services exposed by that site to use their data.

for example, google services, or facebook services, or twitter services
0
 
LVL 47

Expert Comment

by:for_yan
ID: 37755883
This is a simple working example of implementation of getting RSS feed form
the list of sites

It uses ROME API, let me find the appropriate link

import java.io.*;
import java.net.URL;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.StringTokenizer;

import com.sun.syndication.feed.synd.SyndEntry;
import com.sun.syndication.feed.synd.SyndFeed;
import com.sun.syndication.io.SyndFeedInput;
import com.sun.syndication.io.XmlReader;

public class Reader {

 static String [] urls =  {"http://rss.cnn.com/rss/cnn_topstories.rss", "http://www.nytimes.com/services/xml/rss/nyt/World.xml",
 "http://www.nytimes.com/services/xml/rss/nyt/US.xml","http://newsrack.in/crawled.feeds/frontline.rss.xml"
};
public static void main(String[] args) throws Exception {                              

//URL url = new URL("http://viralpatel.net/blogs/feed");

  //  URL url = new URL("http://rss.cnn.com/rss/cnn_topstories.rss");
XmlReader reader = null;

try {

    while(true) {

long now = (new java.util.Date()).getTime();

    System.out.println("checking at " + (new Date(now)).toString());    
long week_before = now - (24L*3600L*7L*1000L);


ArrayList list = new ArrayList();

DataInputStream in = new DataInputStream(new FileInputStream("C:\\temp\\test\\visited.txt"));
PrintStream psout = new PrintStream(new FileOutputStream("C:\\temp\\test\\visited1.txt"));

String buff = null;

while((buff=in.readLine()) != null){
StringTokenizer t = new StringTokenizer(buff);
String ttime = t.nextToken();
if(Long.parseLong(ttime) <week_before)continue;
String llink = t.nextToken().trim();
list.add(llink);
psout.println(ttime + " " + llink);

}

          for (int jj=0; jj<urls.length; jj++){
            URL  url = new URL(urls[jj]);
reader = new XmlReader(url);
SyndFeed feed = new SyndFeedInput().build(reader);
//System.out.println("Feed Title: "+ feed.getAuthor());

for (Iterator i = feed.getEntries().iterator(); i.hasNext();) {
SyndEntry entry = (SyndEntry) i.next();
    String title = entry.getTitle();
     String link = entry.getUri().trim();
     if(list.contains(link))continue;
     Date date = entry.getPublishedDate();
// Problem here -->         **     SyndEntry source = item.getSource();
     String description;
     if (entry.getDescription()== null){
       description = "";
     } else {
       description = entry.getDescription().getValue();
     }
     String cleanDescription = description.replaceAll("\\<.*?>","").replaceAll("\\s+", " ");
        System.out.println(title);
System.out.println(link);
    System.out.println(cleanDescription);



//System.out.println(entry.getTitle());
//System.out.println(entry.getContents());
    System.out.println("");
     System.out.println("");
     psout.println(now + " " + link);
}

}

in.close();
psout.close();
File f0 = new File("C:\\temp\\test\\visited.txt");
File f1 = new File("C:\\temp\\test\\visited1.txt");
f0.delete();
f1.renameTo(f0);

Thread.currentThread().sleep(600000);

    }


} finally {
if (reader != null)
reader.close();
}
}
}
                                            

Open in new window

0
 
LVL 47

Expert Comment

by:for_yan
ID: 37755889
0

Featured Post

On Demand Webinar: Networking for the Cloud Era

Did you know SD-WANs can improve network connectivity? Check out this webinar to learn how an SD-WAN simplified, one-click tool can help you migrate and manage data in the cloud.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Java contains several comparison operators (e.g., <, <=, >, >=, ==, !=) that allow you to compare primitive values. However, these operators cannot be used to compare the contents of objects. Interface Comparable is used to allow objects of a cl…
Introduction Java can be integrated with native programs using an interface called JNI(Java Native Interface). Native programs are programs which can directly run on the processor. JNI is simply a naming and calling convention so that the JVM (Java…
Viewers learn about the third conditional statement “else if” and use it in an example program. Then additional information about conditional statements is provided, covering the topic thoroughly. Viewers learn about the third conditional statement …
Viewers learn about the scanner class in this video and are introduced to receiving user input for their programs. Additionally, objects, conditional statements, and loops are used to help reinforce the concepts. Introduce Scanner class: Importing…
Suggested Courses

628 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question