ObjectBox example: Cache query and multi-threaded usage of cached query

Stresser.java

package io.objectbox.test.stress;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

import io.objectbox.Box;
import io.objectbox.BoxStore;
import io.objectbox.query.Query;

public class Stresser {
    static final boolean VERBOSE = false;

    private final BoxStore store;
    private final Query<TempData> findFirstQuery;
    ThreadPoolExecutor pool;

    public Stresser(BoxStore store) {
        this.store = store;
        findFirstQuery = store.boxFor(TempData.class).query().equal(TempData_.longVal, 0L).build();

        // Originally at 128 threads, decrease to go well with default value of readers
        pool = new ThreadPoolExecutor(5, 100, 7L, TimeUnit.SECONDS, new OfferLinkedBlockingQueue());
    }

    protected void runFindFirstQueries() {
        for (int i = 0; i < 2000; i++) {
            final int j = i;

            Runnable r = new Runnable() {
                @Override
                public void run() {
                    TempData data;
                    synchronized (findFirstQuery) {
                        data = findFirstQuery.setParameter(TempData_.longVal, (long) j).findFirst();
                    }
                    if (VERBOSE) System.out.println(data);
                }
            };
            pool.execute(r);
        }
    }

}