How to pass parameter to already running thread in java?

Question

How to pass parameter to already running thread in java - not in the constructor, and, possibly, without using wait () (maybe ??)

Something similar to a comment in How to pass a parameter to a Java thread?

Do you mean passing a parameter to an already running thread? Because all current answers relate to passing parameters to new threads ... - Valentin Rocher

[edit]

yes, I was looking for something like a producer / consumer pattern.

I need something like a stream in which there is processing and is ready for keyboard input. Another thread is simply to control the network and pass on the received text to the processing thread.

Answer 1

Perhaps you really need a queue lock. When you create a thread, you pass the lock queue internally, and the thread should continue to check if there is any item in the queue. Outside a thread, you can queue items while the thread is "running." Blocking a queue can prevent a thread from exiting if not done.

public class Test { public static void main(String... args) { final BlockingQueue<String> queue = new LinkedBlockingQueue<String>(); Thread running = new Thread(new Runnable() { @Override public void run() { while (true) { try { String data = queue.take(); //handle the data } catch (InterruptedException e) { System.err.println("Error occurred:" + e); } } } }); running.start(); // Send data to the running thread for (int i = 0; i < 10; i++) { queue.offer("data " + i); } } 

}

Answer 2

The “other stream” will have its own life, so you will not be able to communicate with it / pass parameters if it does not actively read what you give it.

A stream with which you can communicate with it usually reads data from some buffer queue.

Take a look at ArrayBlockingQueue , and read on the Consumer-Producer template.

Answer 3

 public class T1 implements Runnable { //parameter of thread T1 public static AtomicBoolean flag = new AtomicBoolean(); @Override public void run() { } } public class T2 implements Runnable { @Override public void run() { //parameter to an already running thread T1.flag.set(true); } } 

Answer 4

How about this way:

  class TestRun implements Runnable { private int testInt = -1; public void setInt(int i) { this.testInt = i; } @Override public void run() { while (!isFinishing()) { System.out.println("Working thread, int : " + testInt); try { Thread.sleep(2500); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } } 

.....

  TestRun first = new TestRun(); TestRun second = new TestRun(); (new Thread(first)).start(); (new Thread(second)).start(); try { Thread.sleep(5000); } catch (InterruptedException e) { } first.setInt(101); second.setInt(102);