Dubbo源码学习--BroadcastCluster集群容错（三）

Broadcast Cluster

广播调用所有提供者，逐个调用，任意一台报错则报错 ​​2​​。通常用于通知所有提供者更新缓存或日志等本地资源信息。

public class BroadcastCluster implements Cluster {

    public <T> Invoker<T> join(Directory<T> directory) throws RpcException {
        //广播调用的处理操作在BroadcastClusterInvoker中
        return new BroadcastClusterInvoker<T>(directory);
    }

}      

public class BroadcastClusterInvoker<T> extends AbstractClusterInvoker<T> {

    private static final Logger logger = LoggerFactory.getLogger(BroadcastClusterInvoker.class);

    public BroadcastClusterInvoker(Directory<T> directory) {
        super(directory);
    }

    @SuppressWarnings({"unchecked", "rawtypes"})
    public Result doInvoke(final Invocation invocation, List<Invoker<T>> invokers, LoadBalance loadbalance) throws RpcException {
        checkInvokers(invokers, invocation);
        RpcContext.getContext().setInvokers((List) invokers);
        RpcException exception = null;
        Result result = null;
        //依次调用所有的服务，不需要负载均衡策略
        for (Invoker<T> invoker : invokers) {
            try {
                result = invoker.invoke(invocation);
            } catch (RpcException e) {
                exception = e;
                logger.warn(e.getMessage(), e);
            } catch (Throwable e) {
                exception = new RpcException(e.getMessage(), e);
                logger.warn(e.getMessage(), e);
            }
        }
        //只要存在某个服务调用失败就抛出异常
        if (exception != null) {
            throw exception;
        }
        return result;
    }

}