Dubbo 的集群容错模式：Broadcast Cluster（广播模式）

<dubbo:service cluster="broadcast" />

<dubbo:reference cluster="broadcast" />

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

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

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

    @Override
    @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;
        // 广播到所有的被调用实例
        for (Invoker<T> invoker : invokers) {
            try {
                result = invoker.invoke(invocation);
            } catch (RpcException e) {
                // 记录异常
                exception = e;
                logger.warn(e.getMessage(), e);
            } catch (Throwable e) {
                // 记录异常
                exception = new RpcException(e.getMessage(), e);
                logger.warn(e.getMessage(), e);
            }
        }
        // 只要有一个实例有异常则报错
        if (exception != null) {
            throw exception;
        }
        return result;
    }

}