Twitter authentication credentials - twitter

Question

I am new to the social network analysis and twitter API.I wanted to collect tweets on certain topic .So i have written the following code
package com;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.List;
import twitter4j.Query;
import twitter4j.QueryResult;
import twitter4j.Status;
import twitter4j.Tweet;
import twitter4j.Twitter;
import twitter4j.TwitterException;
import twitter4j.TwitterFactory;
public class TwitterSearchAdvance {
public static void main(String[] vishal) throws TwitterException,
IOException {
// List<Tweet> Data = new ArrayList<Tweet>();
StringBuffer stringbuffer = new StringBuffer();
Twitter twitter = new TwitterFactory().getInstance();
for (int page = 0; page <= 4; page++) {
Query query = new Query("Airtel");
// query.setRpp(100); // 100 results per page
QueryResult qr = twitter.search(query);
List<Status> qrTweets = qr.getTweets();
System.out.println("-------------------" + qrTweets.size());
// break out if there are no more tweets
for (Status t : qrTweets) {
System.out.println(t.getCreatedAt() + ": " + t.getText());
stringbuffer.append(t);
stringbuffer.append("\n");
BufferedWriter bw = new BufferedWriter(new FileWriter(new File(
"/home/vishal/FirstDocu.txt"), true));
bw.write(stringbuffer.toString());
bw.newLine();
// bw.write(t.getCreatedAt() + ": " + t.getText());
bw.close();
}
}
}
}
But when i run the following program the following error starts coming
Exception in thread "main" java.lang.IllegalStateException: Authentication credentials are missing. See http://twitter4j.org/configuration.html for the detail.
at twitter4j.TwitterBaseImpl.ensureAuthorizationEnabled(TwitterBaseImpl.java:200)
at twitter4j.TwitterImpl.get(TwitterImpl.java:1833)
at twitter4j.TwitterImpl.search(TwitterImpl.java:282)
at com.TwitterSearchAdvance.main(TwitterSearchAdvance.java:28)
Where do i need to provide credentials in my program
Thanks

Answer 1

Have a look at the options here http://twitter4j.org/en/configuration.html
There are a number of ways to provide credentials to your program:
Properties File
ConfigurationBuilder class
System properties
Environment Variables
All details and instructions can be found in the link