[享学Netflix] 四十一、Ribbon核心API源码解析：ribbon-core（四）ClientException客户端异常

public class ScheduledThreadPoolExectuorWithDynamicSize extends ScheduledThreadPoolExecutor {
	...
	// 注意此处使用的DynamicIntProperty，因此具有动态性，且是实时的哦
	// ThreadFactory：生产Thread，用于任务执行
	public ScheduledThreadPoolExectuorWithDynamicSize(final DynamicIntProperty corePoolSize, ThreadFactory threadFactory) {
		super(corePoolSize.get(), threadFactory);

		// 通过DynamicIntProperty的回调机制实现coreSize的动态调整
		corePoolSize.addCallback(() -> {setCorePoolSize(corePoolSize.get());});
		...
	}
}

@Test
public void fun6() throws InterruptedException {
    // =========准备一个动态属性==========
    DynamicIntProperty poolCoreSize = DynamicPropertyFactory.getInstance().getIntProperty("myThreadPoolCoreSize", 2);
    ThreadFactory threadFactory = new ThreadFactory() {
        private AtomicInteger count = new AtomicInteger();

        @Override
        public Thread newThread(Runnable r) {
            Thread thread = new Thread(r);
            thread.setName("myThreadPrefix-" + count.incrementAndGet());
            thread.setDaemon(true);
            return thread;
        }
    };

    ScheduledThreadPoolExectuorWithDynamicSize exectuor = new ScheduledThreadPoolExectuorWithDynamicSize(poolCoreSize, threadFactory);

    // 启动3个定时任务（默认coreSize是2哦）
    for (int i = 1; i <= 3; i++) {
        int index = i;
        exectuor.scheduleAtFixedRate(() -> {
            String currThreadName = Thread.currentThread().getName();
            int corePoolSize = exectuor.getCorePoolSize();
            System.out.printf("我是%s号任务，线程名是[%s]，线程池核心数是：%s\n", index, currThreadName, corePoolSize);
        }, index, 3, TimeUnit.SECONDS);
    }

    // 阻塞主线程
    TimeUnit.MINUTES.sleep(100);
}

myThreadPoolCoreSize=2

...
我是1号任务，线程名是[myThreadPrefix-1]，线程池核心数是：2
我是2号任务，线程名是[myThreadPrefix-2]，线程池核心数是：2
我是3号任务，线程名是[myThreadPrefix-1]，线程池核心数是：2
我是1号任务，线程名是[myThreadPrefix-2]，线程池核心数是：2
我是2号任务，线程名是[myThreadPrefix-1]，线程池核心数是：2
17:23:36.690 [pollingConfigurationSource] DEBUG com.netflix.config.AbstractPollingScheduler - Polling started
17:23:36.691 [pollingConfigurationSource] DEBUG com.netflix.config.DynamicPropertyUpdater - updating property key [myThreadPoolCoreSize], value [3]
我是3号任务，线程名是[myThreadPrefix-2]，线程池核心数是：3
我是1号任务，线程名是[myThreadPrefix-1]，线程池核心数是：3
我是2号任务，线程名是[myThreadPrefix-3]，线程池核心数是：3
我是3号任务，线程名是[myThreadPrefix-2]，线程池核心数是：3
我是1号任务，线程名是[myThreadPrefix-1]，线程池核心数是：3
我是2号任务，线程名是[myThreadPrefix-3]，线程池核心数是：3
...

public abstract class Resources {

	// 有且仅有一个方法
	public static URL getResource(String resourceName) {
		URL url = null;
		ClassLoader loader = Thread.currentThread().getContextClassLoader();
		...
			//1、使用ClassLoader从context classpath里加载资源
			url = loader.getResource(resourceName);
			//2、从system classpath下加载资源
			url = ClassLoader.getSystemResource(resourceName);
			
			//3、通过文件系统加载资源
			resourceName = URLDecoder.decode(resourceName, "UTF-8");
			url = (new File(resourceName)).toURI().toURL();
		...
		return url;
	}
}

@Test
public void fun7(){
    URL resource = Resources.getResource("config.properties");
    System.out.println(resource);
}

com.netflix.client.ClientException: Load balancer does not have available server for client

public class ClientException extends Exception{

    protected int errorCode;
    protected String message; // 错误消息
    protected Object errorObject; // 错误实体
    protected ErrorType errorType = ErrorType.GENERAL;
}

ClientException：

    public enum ErrorType{
        GENERAL, 
        CONFIGURATION, 
        NUMBEROF_RETRIES_EXEEDED, 
        NUMBEROF_RETRIES_NEXTSERVER_EXCEEDED, 
        SOCKET_TIMEOUT_EXCEPTION, 
        READ_TIMEOUT_EXCEPTION,
        UNKNOWN_HOST_EXCEPTION,
        CONNECT_EXCEPTION,
        CLIENT_THROTTLED,
        SERVER_THROTTLED,
        NO_ROUTE_TO_HOST_EXCEPTION,
        CACHE_MISSING;
	}