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POJava Synchronized and Threads
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copied!<p>I'm having issues with Synchronized not behaving the way i expect, i tried using volatile keyword also:</p> <p>Shared Object:</p> <pre><code>public class ThreadValue { private String caller; private String value; public ThreadValue( String caller, String value ) { this.value = value; this.caller = caller; } public synchronized String getValue() { return this.caller + " " + this.value; } public synchronized void setValue( String caller, String value ) { this.caller = caller; this.value = value; } } </code></pre> <p>Thread 1:</p> <pre><code>class CongoThread implements Runnable { private ThreadValue v; public CongoThread(ThreadValue v) { this.v = v; } public void run() { for (int i = 0; i < 10; i++) { v.setValue( "congo", "cool" ); v.getValue(); } } } </code></pre> <p>Thread 2:</p> <pre><code>class CongoThread implements Runnable { private ThreadValue v; public CongoThread(ThreadValue v) { this.v = v; } public void run() { for (int i = 0; i < 10; i++) { v.setValue( "congo", "lame" ); v.getValue(); } } } </code></pre> <p>Calling Class:</p> <pre><code>class TwoThreadsTest { public static void main (String args[]) { ThreadValue v = new ThreadValue("", ""); Thread congo = new Thread( new CongoThread( v ) ); Thread libya = new Thread( new LibyaThread( v ) ); libya.start(); congo.start(); } } </code></pre> <p>Occasionally i get <code>"In Libya Thread congo cool"</code> which should never happen. I expect only:<br> <code>"In Libya Thread libya awesome"</code><br> <code>"In Congo Thread congo cool"</code></p> <p>I dont expect them to be mixed.</p>

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