Twitter身份验证错误“身份验证凭据丢失”

Question

I have the following code for using the Twitter API in Java

import java.io.File;
import java.io.PrintWriter;
import java.util.List;
import twitter4j.Query;
import twitter4j.QueryResult;
import twitter4j.Status;
import twitter4j.Twitter;
import twitter4j.TwitterFactory;
import twitter4j.conf.ConfigurationBuilder;

public class TwitterDataCollector {

    public static void main(String[] args) throws Exception {

        ConfigurationBuilder cb = new ConfigurationBuilder();

        cb.setDebugEnabled(true)
          .setOAuthConsumerKey(comsumerKey)
          .setOAuthConsumerSecret(consumerSecret)
          .setOAuthAccessToken(accesstoken)
          .setOAuthAccessTokenSecret(accesstokensecret);

        TwitterFactory tf = new TwitterFactory(cb.build());
        Twitter twitter = tf.getInstance();

        //PrintWriter tweetWriter = null;
         twitter = TwitterFactory.getSingleton();
        List<Status> statuses = twitter.getHomeTimeline();
        System.out.println("Showing home timeline.");

        for (Status status : statuses) {
            System.out.println(status.getUser().getName() + ":" + status.getText());
        }
    }
}

I am trying to authenticate to the Twitter API with consumer key and access token and trying to access my timeline but it is showing

Exception in thread "main" 
java.lang.IllegalStateException: Authentication credentials are missing. See http://twitter4j.org/en/configuration.html for details
at twitter4j.TwitterBaseImpl.ensureAuthorizationEnabled(TwitterBaseImpl.java:186)
at twitter4j.TwitterImpl.get(TwitterImpl.java:1554)
at twitter4j.TwitterImpl.getHomeTimeline(TwitterImpl.java:105)
at TwitterDataCollector.main(TwitterDataCollector.java:24)

Answer 1

The removal of the line

twitter = TwitterFactory.getSingleton();

Resolves your issue; getInstance() is returning you a Twitter using the auth details you specified in the ConfigurationBuilder .

If you want to use getSingleton() you will need to do some priming of the ConfigurationContext with your auth details. I'd hope that there is some documentation on how this should be done

On a side note I would reccommend not posting your OAuth keys to a public website