import java.util.concurrent.ThreadPoolExecutor;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;

@Configuration
@EnableAsync
public class ThreadPool {
	public static final int DEFAULT_THREADS_NUMS = 2 * Runtime.getRuntime().availableProcessors();
	@Bean("taskExecutor")
	public ThreadPoolTaskExecutor taskExecutor() {
		ThreadPoolTaskExecutor threadPoolTaskExecutor = new ThreadPoolTaskExecutor();

		int maxPoolSize = 2 * DEFAULT_THREADS_NUMS;
		threadPoolTaskExecutor.setCorePoolSize(DEFAULT_THREADS_NUMS);
		threadPoolTaskExecutor.setMaxPoolSize(maxPoolSize);
		threadPoolTaskExecutor.setQueueCapacity(maxPoolSize);
		threadPoolTaskExecutor.setKeepAliveSeconds(60);
		threadPoolTaskExecutor.setThreadNamePrefix("Async-Thread-");
		threadPoolTaskExecutor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());

		return threadPoolTaskExecutor;
	}
}