如何使用Java实现可运行

Question

I am trying to create a program that will carry on running automatically without me having to do anything. I am a bit confused on how to implement runnable in java so I can create a thread that will go to sleep for a certain period of time and then run the re-run the program after the sleep period is over.

public class work {

public static void main(String[] args) throws IOException, InterruptedException {

    work test = new work();
    test.information();

}

private ConfigurationBuilder OAuthBuilder() {
    ConfigurationBuilder cb = new ConfigurationBuilder();
    cb.setOAuthConsumerKey("dy1Vcv3iGYTqFif6m4oYpGBhq");
    cb.setOAuthConsumerSecret("wKKJ1XOPZbxX0hywDycDcZf40qxfHvkDXYdINWYXGUH04qU0ha");
    cb.setOAuthAccessToken("4850486261-49Eqv5mogjooJr8lm86hB20QRUpxeHq5iIzBLks");
    cb.setOAuthAccessTokenSecret("QLeIKTTxJOwpSX4zEasREtGcXcqr0mY8wk5hRZKYrH5pd");
    return cb; 



}

public void information() throws IOException, InterruptedException {

    ConfigurationBuilder cb = OAuthBuilder();
    Twitter twitter = new TwitterFactory(cb.build()).getInstance();
    try {
        User user = twitter.showUser("ec12327");
        Query query = new Query("gym fanatic");
        query.setCount(100);
        query.lang("en");
        String rawJSON =null ;
        String statusfile = null;
        int i=0;

    try {     

                QueryResult result = twitter.search(query);
                for(int z = 0;z<5;z++){
                for( Status status : result.getTweets()){

                    System.out.println("@" + status.getUser().getScreenName() + ":" + status.getText());

                       rawJSON = TwitterObjectFactory.getRawJSON(status);
                         statusfile = "results" + z +".txt";
                        storeJSON(rawJSON, statusfile);

                        i++;

                }
    }


                System.out.println(i);

              }   
              catch(TwitterException e) {         
                System.out.println("Get timeline: " + e + " Status code: " + e.getStatusCode());
                if(e.getErrorCode() == 88){
                    Thread.sleep(900);
                    information();

                }
              }     


    } catch (TwitterException e) {
        if (e.getErrorCode() == 88) {
            System.err.println("Rate Limit exceeded!!!!!!");
            Thread.sleep(90);
            information();
            try {
                long time = e.getRateLimitStatus().getSecondsUntilReset();
                if (time > 0)
                    Thread.sleep(900000);
                    information();
            } catch (InterruptedException e1) {
                e1.printStackTrace();
            }
        }
    }
}

 private static void storeJSON(String rawJSON, String fileName) throws IOException {
        FileWriter fileWriter = null;
        try
        {
            fileWriter = new FileWriter(fileName, true);
            fileWriter.write(rawJSON);
            fileWriter.write("\n");
        }
        catch(IOException ioe)
        {
            System.err.println("IOException: " + ioe.getMessage());
        } finally {
            if(fileWriter!=null) {
                fileWriter.close();
            }
        }
    }

}

Answer 1

You have severable options to implement a thread in Java.

Implementing Runnable

When a class implements the Runnable interface, he has to override the run() method. This runnable can be passed to the constructor of a Thread . This thread can then be executed using the start() method. If you'd like to have this thread run forever and sleep, you could do something like the following:

public class HelloRunnable implements Runnable {
    public void run() {
        while(true){
            Thread.sleep(1000);
            System.out.println("Hello from a thread!");
        }
    }

    public static void main(String args[]) {
        (new Thread(new HelloRunnable())).start();
    }
}

Extending Thread

Thread itself also has a run() method. When extending thread, you can override the Thread's run() method and provide your own implementation. Then you'd have to instantiate your own custom thread, and start it in the same way. Again, like the previous you could do this:

public class HelloThread extends Thread {
    public void run() {
        while(true){
            Thread.sleep(1000);
            System.out.println("Hello from a thread!");
        }
    }

    public static void main(String args[]) {
        (new HelloThread()).start();
    }
}

Source: Oracle documentation

Answer 2

Building on the previous answer, you need to either extend Thread or implement Runnable on your Work class. Extending Thread is probably easier.

public class work extends Thread {

    public void run() {
        // your app will run forever, consider a break mechanism
        while(true) {
            // sleep for a while, otherwise you'll max your CPU
            Thread.sleep( 1000 );
            this.information();
        }
    }

    public static void main(String[] args) throws IOException,    InterruptedException {
        work test = new work();
        test.start();
   }

    // ... rest of your class
 }

Answer 3

public static void main(String[] args){
    Thread thread = new Thread(runnable); // create new thread instance
    thread.start(); // start thread
}


public static Runnable runnable = new Runnable(){
    @Override
    public void run(){

      final int DELAY = 500;
      while(true){
          try{
               // Code goes here;
               Thread.sleep(DELAY)
          } catch(Exception e){
              e.printStackTrace();                    
          }

      }

   }

}