org.apache.dubbo.rpc

Interface Filter

All Known Subinterfaces:

Filter

All Known Implementing Classes:

AccessLogFilter, ActiveLimitFilter, CacheFilter, ClassLoaderFilter, CompatibleFilter, ConsumerContextFilter, ContextFilter, DeprecatedFilter, EchoFilter, ExceptionFilter, ExecuteLimitFilter, FutureFilter, GenericFilter, GenericImplFilter, ListenableFilter, MetricsFilter, MonitorFilter, TimeoutFilter, TokenFilter, TpsLimitFilter, TraceFilter, ValidationFilter

@SPI
public interface Filter

Extension for intercepting the invocation for both service provider and consumer, furthermore, most of functions in dubbo are implemented base on the same mechanism. Since every time when remote method is invoked, the filter extensions will be executed too, the corresponding penalty should be considered before more filters are added.

  They way filter work from sequence point of view is
    
    ...code before filter ...
          invoker.invoke(invocation) //filter work in a filter implementation class
          ...code after filter ...
    
    Caching is implemented in dubbo using filter approach. If cache is configured for invocation then before
    remote call configured caching type's (e.g. Thread Local, JCache etc) implementation invoke method gets called.
 

Filter. (SPI, Singleton, ThreadSafe)

See Also:

GenericFilter, EchoFilter, TokenFilter, TpsLimitFilter

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	Filter.Listener

Method Summary

Modifier and Type	Method and Description
Result	invoke(Invoker<?> invoker, Invocation invocation) Does not need to override/implement this method.
default Result	onResponse(Result appResponse, Invoker<?> invoker, Invocation invocation) Deprecated.

Method Detail

invoke

Result invoke(Invoker<?> invoker,
              Invocation invocation)
       throws RpcException

Does not need to override/implement this method.

Throws:

RpcException

onResponse

@Deprecated
default Result onResponse(Result appResponse,
                                      Invoker<?> invoker,
                                      Invocation invocation)

Deprecated.

Filter itself should only be response for passing invocation, all callbacks has been placed into Filter.Listener

Parameters:

appResponse -

invoker -

invocation -

Returns: