SharedEngineThreads.java

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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
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import java.util.concurrent.CountDownLatch;
import javax.script.*;
import org.openjdk.engine.python.PythonScriptEngine;

void main(String[] args) throws Exception {
    var m = new ScriptEngineManager();
    var e = (PythonScriptEngine) m.getEngineByName("python");
    IO.println(Thread.currentThread());
    IO.println("engine created " + e + ", isMainEngine? " + e.isMainEngine());
    e.eval("print('main thread " + Thread.currentThread() + "')");

    int num = args.length > 0 ? Integer.parseInt(args[0]) : 1;
    var countDownLatch = new CountDownLatch(num);
    for (int i = 0; i < num; i++) {
        new Thread(() -> {
            IO.println(Thread.currentThread());
            try {
                e.withPyThreadState(() -> {
                    try {
                        e.eval("print('in thread " + Thread.currentThread() + "')");
                    } catch (ScriptException ex) {
                        ex.printStackTrace(System.err);
                    }
                });
            } finally {
                countDownLatch.countDown();
            }
        }).start();
    }

    countDownLatch.await();
    IO.println("closing main engine");
    e.close();
}