java.lang.Object
- io.grpc.LoadBalancer.Subchannel
- - io.grpc.util.ForwardingSubchannel

@ExperimentalApi("https://github.com/grpc/grpc-java/issues/1771")
public abstract class ForwardingSubchannel
extends LoadBalancer.Subchannel

Constructor Summary

Constructors
Constructor Description

ForwardingSubchannel()

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`Channel`	`asChannel()`	(Internal use only) returns a `Channel` that is backed by this Subchannel.
`protected abstract LoadBalancer.Subchannel`	`delegate()`	Returns the underlying Subchannel.
`java.util.List<EquivalentAddressGroup>`	`getAllAddresses()`	Returns the addresses that this Subchannel is bound to.
`Attributes`	`getAttributes()`	The same attributes passed to `Helper.createSubchannel()`.
`ChannelLogger`	`getChannelLogger()`	Returns a `ChannelLogger` for this Subchannel.
`java.lang.Object`	`getInternalSubchannel()`	(Internal use only) returns an object that represents the underlying subchannel that is used by the Channel for sending RPCs when this `LoadBalancer.Subchannel` is picked.
`void`	`requestConnection()`	Asks the Subchannel to create a connection (aka transport), if there isn't an active one.
`void`	`shutdown()`	Shuts down the Subchannel.
`void`	`start(LoadBalancer.SubchannelStateListener listener)`	Starts the Subchannel.
`java.lang.String`	`toString()`
`void`	`updateAddresses(java.util.List<EquivalentAddressGroup> addrs)`	Replaces the existing addresses used with this `Subchannel`.

Methods inherited from class io.grpc.LoadBalancer.Subchannel
getAddresses

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - ForwardingSubchannel
```
public ForwardingSubchannel()
```
- Method Detail
  - delegate
```
protected abstract LoadBalancer.Subchannel delegate()
```
    Returns the underlying Subchannel.
  - start
```
public void start(LoadBalancer.SubchannelStateListener listener)
```
    Description copied from class: LoadBalancer.Subchannel
    
    Starts the Subchannel. Can only be called once.
    Must be called prior to any other method on this class, except for LoadBalancer.Subchannel.shutdown() which may be called at any time.
    Must be called from the Synchronization Context, otherwise it may throw. See #5015 for more discussions.
    
    Overrides:
    
    start in class LoadBalancer.Subchannel
    
    Parameters:
    
    listener - receives state updates for this Subchannel.
  - shutdown
```
public void shutdown()
```
    Description copied from class: LoadBalancer.Subchannel
    
    Shuts down the Subchannel. After this method is called, this Subchannel should no longer be returned by the latest picker, and can be safely discarded.
    Calling it on an already shut-down Subchannel has no effect.
    It should be called from the Synchronization Context. Currently will log a warning if violated. It will become an exception eventually. See #5015 for the background.
    
    Specified by:
    
    shutdown in class LoadBalancer.Subchannel
  - requestConnection
```
public void requestConnection()
```
    Description copied from class: LoadBalancer.Subchannel
    
    Asks the Subchannel to create a connection (aka transport), if there isn't an active one.
    It should be called from the Synchronization Context. Currently will log a warning if violated. It will become an exception eventually. See #5015 for the background.
    
    Specified by:
    
    requestConnection in class LoadBalancer.Subchannel
  - getAllAddresses
```
public java.util.List<EquivalentAddressGroup> getAllAddresses()
```
    Description copied from class: LoadBalancer.Subchannel
    
    Returns the addresses that this Subchannel is bound to. The returned list will not be empty.
    It should be called from the Synchronization Context. Currently will log a warning if violated. It will become an exception eventually. See #5015 for the background.
    
    Overrides:
    
    getAllAddresses in class LoadBalancer.Subchannel
  - getAttributes
```
public Attributes getAttributes()
```
    Description copied from class: LoadBalancer.Subchannel
    
    The same attributes passed to Helper.createSubchannel(). LoadBalancer can use it to attach additional information here, e.g., the shard this Subchannel belongs to.
    
    Specified by:
    
    getAttributes in class LoadBalancer.Subchannel
  - asChannel
```
public Channel asChannel()
```
    Description copied from class: LoadBalancer.Subchannel
    (Internal use only) returns a Channel that is backed by this Subchannel. This allows a LoadBalancer to issue its own RPCs for auxiliary purposes, such as health-checking, on already-established connections. This channel has certain restrictions:
    
    It can issue RPCs only if the Subchannel is READY. If Channel.newCall(io.grpc.MethodDescriptor<RequestT, ResponseT>, io.grpc.CallOptions) is called when the Subchannel is not READY, the RPC will fail immediately.
    
    It doesn't support wait-for-ready RPCs. Such RPCs will fail immediately.
    
    RPCs made on this Channel is not counted when determining ManagedChannel's idle mode. In other words, they won't prevent ManagedChannel from entering idle mode.
    Warning: RPCs made on this channel will prevent a shut-down transport from terminating. If you make long-running RPCs, you need to make sure they will finish in time after the Subchannel has transitioned away from READY state (notified through LoadBalancer.handleSubchannelState(io.grpc.LoadBalancer.Subchannel, io.grpc.ConnectivityStateInfo)).
    Warning: this is INTERNAL API, is not supposed to be used by external users, and may change without notice. If you think you must use it, please file an issue.
    Overrides:
    
    asChannel in class LoadBalancer.Subchannel
  - getChannelLogger
```
public ChannelLogger getChannelLogger()
```
    Description copied from class: LoadBalancer.Subchannel
    
    Returns a ChannelLogger for this Subchannel.
    
    Overrides:
    
    getChannelLogger in class LoadBalancer.Subchannel
  - getInternalSubchannel
```
public java.lang.Object getInternalSubchannel()
```
    Description copied from class: LoadBalancer.Subchannel
    
    (Internal use only) returns an object that represents the underlying subchannel that is used by the Channel for sending RPCs when this LoadBalancer.Subchannel is picked. This is an opaque object that is both provided and consumed by the Channel. Its type is not Subchannel.
    Warning: this is INTERNAL API, is not supposed to be used by external users, and may change without notice. If you think you must use it, please file an issue and we can consider removing its "internal" status.
    
    Overrides:
    
    getInternalSubchannel in class LoadBalancer.Subchannel
  - updateAddresses
```
public void updateAddresses(java.util.List<EquivalentAddressGroup> addrs)
```
    Description copied from class: LoadBalancer.Subchannel
    
    Replaces the existing addresses used with this Subchannel. If the new and old addresses overlap, the Subchannel can continue using an existing connection.
    It must be called from the Synchronization Context or will throw.
    
    Overrides:
    
    updateAddresses in class LoadBalancer.Subchannel
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object

Class ForwardingSubchannel

Constructor Summary

Method Summary

Methods inherited from class io.grpc.LoadBalancer.Subchannel

Methods inherited from class java.lang.Object

Constructor Detail

ForwardingSubchannel

Method Detail

delegate

start

shutdown

requestConnection

getAllAddresses

getAttributes

asChannel

getChannelLogger

getInternalSubchannel

updateAddresses

toString