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copied!<p>A general way to do these kinds of tasks is, first, create a class to hold the results you want to get from each thread:</p> <pre><code>final class PingResult { public String ip; public String hostname; //... other things you want go here } </code></pre> <p>Then create a callable that does the actual work</p> <pre><code>class PingTask extends Callable<PingResult>{ private final String gateWayKey, subNetKey; //... other parameters you need go here public Ping( String gwKey, String snKey /*+ others? */ ){ // This is just a way to pass parameters to your pinging function this.gateWayKey = gwKey; this.subNetKey = snKey; // ... } public PingResult call(){ // Do actual pinging work here if ( /* Success */ ) { PingResult result = new PingResult(); result.ip= /*Fill these in*/; result.hostname = /* ... */; return result; } // Otherwise we failed, I'm using null as a failure sentinel // (you can come up with something better) return null; } } </code></pre> <p>Then in your calling code, set up a thread pool, cue up the requests, and then process the results.</p> <pre><code>// Might need to tweak the # for best performance final int NUM_THREADS = Runtime.getRuntime.availableProcesses(); ExecutorService exec = Executors.newFixedThreadPool( NUM_THREADS ); List<Future<PingResult>> results = new ArrayList<PingResult>(); for(/* ... */){ results.add( exec.submit( new PingTask( gateway, subnet ) ) ); } for( Future<PingResult> future : results ){ PingResult result = future.get(); // Process the result here (this is where you insert into the DB) } exec.shutdown(); // VERY IMPORTANT. If you don't do this the JVM will never stop. </code></pre>

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