开发者

Java. Simple TimerTask for each value of array

I have problem with printing out the each value of certain array with certain duration of time. For example I have array with values: "Value1", "Value2", "Value3". I want to o开发者_StackOverflow中文版utput "Value1", after 5 sec "Value2", after 5 second "Value3". Instead, All Values of arrays are printout 3 times. If you could help to me, I will be so gratefull )) Thank you.

Here is my code.

import java.util.Date;

public class Timer2 {

    /**
     * @param args
     */
    public static void main(String[] args) {

        long start = new Date().getTime();

        for (int i = 0; i < 4; i++) {
            new java.util.Timer().schedule(new java.util.TimerTask() {

                public void run() {
                    String[] arrayElements = { "value1", "value2", "value3",
                            "value4" };
                    for (int i = 0; i < arrayElements.length; i++)
                        System.out.println(arrayElements[i]);

                }
            }, new Date(start));
            start += 1000;
        }
    }

}


Solution from my answer in cross-post that uses scheduleAtFixedRate:

import java.util.Timer;
import java.util.TimerTask;

class Timer2 {

   private static final String[] ARRAY_ELEMENTS = {"value1", "value2", "value3", "value4"};

   public static void main(String[] args) {
      final Timer utilTimer = new Timer();
      utilTimer.scheduleAtFixedRate(new TimerTask() {
         private int index = 0;

         public void run() {
            System.out.println(ARRAY_ELEMENTS[index]);
            index++;
            if (index >= ARRAY_ELEMENTS.length) {
               utilTimer.cancel();
            }
         }
      }, 5000L, 5000L);
   }

}


The simplest way to do what you have described you want to do is:

public static void main(String[] args) throws InterruptedException {
    String[] arrayElements = { "value1", "value2", "value3", "value4" };

    for (int i = 0; i < arrayElements.length; i++) {
        System.out.println(arrayElements[i]);
        Thread.sleep(5000);
    }   
}

If you must use a TimerTask then you could do:

public static void main(String[] args) throws InterruptedException {
    String[] arrayElements = { "value1", "value2", "value3",
    "value4" };

    long start = System.currentTimeMillis();

    for (int i = 0; i < arrayElements.length; i++) {
        final String value = arrayElements[i];
         new java.util.Timer().schedule(new java.util.TimerTask() {
                public void run() {
                    System.out.println(value);
                }
         }, new Date(start));

         start += 5000;
    }       
}


You put the print loop in the TimeTask.run() so when it is executed, all the value is printed out at once. What you need to do is to create a time task for each array elements. Something like:

String[] arrayElements = {"value1", "value2", "value3", "value4"};
for (final String arrayElement : arrayElements)
{
  new java.util.Timer().schedule(
    new java.util.TimerTask()
    { 
      public void run()
      {
        System.out.println(arrayElement);
      }
    },
    new Date(start)
  );
  start+=1000;
}

Hope this helps.

0

上一篇:

下一篇:

精彩评论

暂无评论...
验证码 换一张
取 消

最新问答

问答排行榜