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volatile

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The volatile modifier is used in multi threaded programming. If you declare a field as volatile it is a signal to threads that they must read the most recent value, not a locally cached one. Furthermore, volatile reads and writes are guaranteed to be atomic (access to a non-volatile long or double is not atomic), thus avoiding certain read/write errors between multiple threads. 

public class MyRunnable implements Runnable
{
    private volatile boolean active;
 
    public void run(){ // run is called in one thread 
        active = true;
        while (active){
            // some code here
        }
    }
    
    public void stop(){ // stop() is called from another thread
        active = false;
    }
}
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Non-Access Modifiers:
* Non-Access Modifiers
* final
* static
* abstract
* strictfp
* synchronized
* transient
* volatile
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0 Inheritance
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184 Contributors