AsyncPod.java

package com.kryptnostic.rhizome.pods;

import java.lang.reflect.Method;
import java.util.Arrays;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.aop.interceptor.AsyncUncaughtExceptionHandler;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.AsyncConfigurer;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.SchedulingConfigurer;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
import org.springframework.scheduling.config.ScheduledTaskRegistrar;

import com.google.common.eventbus.AsyncEventBus;
import com.google.common.util.concurrent.ListeningExecutorService;
import com.google.common.util.concurrent.MoreExecutors;

@Configuration
@EnableScheduling
@EnableAsync
public class AsyncPod implements AsyncConfigurer, SchedulingConfigurer {
    private static Logger logger = LoggerFactory.getLogger( AsyncPod.class );

    // TODO: Make thread names prefixes configurable.
    @Override
    public void configureTasks( ScheduledTaskRegistrar registrar ) {
        registrar.setScheduler( rhizomeScheduler() );
    }

    @Bean(
        destroyMethod = "shutdown" )
    public ThreadPoolTaskScheduler rhizomeScheduler() {
        ThreadPoolTaskScheduler executor = new ThreadPoolTaskScheduler();
        executor.setPoolSize( 8 );
        executor.setThreadNamePrefix( "rhizome-pulse-" );
        executor.initialize();
        return executor;
    }

    @Override
    @Bean(
        destroyMethod = "shutdown" )
    public ThreadPoolTaskExecutor getAsyncExecutor() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        executor.setCorePoolSize( 4 );
        executor.setMaxPoolSize( 32 );
        executor.setThreadNamePrefix( "rhizome-offshoot-" );
        executor.initialize();
        return executor;
    }

    @Bean
    public ListeningExecutorService listeningExecutorService() {
        return MoreExecutors.listeningDecorator( getAsyncExecutor().getThreadPoolExecutor() );
    }
    
    @Bean
    public AsyncEventBus localConfigurationUpdates() {
        return new AsyncEventBus( getAsyncExecutor() );
    }

    @Override
    public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
        return new AsyncUncaughtExceptionHandler() {
            @Override
            public void handleUncaughtException( Throwable ex, Method method, Object... params ) {
                logger.error(
                        "Error executing async method {} with params {}.",
                        method.getName(),
                        Arrays.asList( params ),
                        ex );
            }
        };
    }

}