/*
 * #%L
 * SciJava library facilitating consistent parallel processing.
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 * Copyright (C) 2021 - 2024 SciJava developers.
 * %%
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 * modification, are permitted provided that the following conditions are met:
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package org.scijava.concurrent;

import java.util.Arrays;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * This demo shows how to use {@link Parallelization} to write a algorithm, that
 * can be run single threaded or multi threaded, or with a given number of
 * threads.
 */
public class ParallelizationDemo {

	public static void main(String... args) {
		System.out.println("\nSingle Threaded:\n================");
		Parallelization.runSingleThreaded(() -> exampleAlgorithm());

		System.out.println("\nMulti Threaded:\n===============");
		Parallelization.runMultiThreaded(() -> exampleAlgorithm());

		System.out.println("\nTwo Threads:\n===============");
		ExecutorService executor = Executors.newFixedThreadPool(2);
		Parallelization.runWithExecutor(executor, () -> exampleAlgorithm());
		executor.shutdown();
	}

	private static void exampleAlgorithm() {
		TaskExecutor taskExecutor = Parallelization.getTaskExecutor();

		System.out.println("Parallelism Level: " + taskExecutor.getParallelism());

		List<Integer> list = Arrays.asList(1, 2, 3, 4);

		taskExecutor.forEach(list, index -> {
			System.out.println("task " + index + " start");
			waitOneSecond();
			System.out.println("task " + index + " finish");
		});
	}

	private static void waitOneSecond() {
		try {
			Thread.sleep(1000);
		}
		catch (InterruptedException e) {
			throw new RuntimeException(e);
		}
	}
}
