import java.io.StringReader;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactory;
import org.xml.sax.InputSource;

public class XPathRepro {

    public static void main(String[] args) throws Exception {
        Runnable r = () -> {
            try {
                XPathExpression expr = XPathFactory.newInstance().newXPath().compile("1+1");
                for (int i = 0; i < 100; i++) {
                    expr.evaluate(new InputSource(new StringReader("<doc/>")));
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        };

        new Thread(r).start();
        new Thread(r).start();
        new Thread(r).start();
        new Thread(r).start();
    }
}