ServerCall (grpc-all 1.0.1 API)

java.lang.Object
- io.grpc.ServerCall<ReqT,RespT>

Type Parameters:

ReqT - parsed type of request message.

RespT - parsed type of response message.

Direct Known Subclasses:

ForwardingServerCall
```
public abstract class ServerCall<ReqT,RespT>
extends Object
```
Encapsulates a single call received from a remote client. Calls may not simply be unary request-response even though this is the most common pattern. Calls may stream any number of requests and responses. This API is generally intended for use by generated handlers, but applications may use it directly if they need to.
Headers must be sent before any messages, which must be sent before closing.
No generic method for determining message receipt or providing acknowledgement is provided. Applications are expected to utilize normal messages for such signals, as a response naturally acknowledges its request.
Methods are guaranteed to be non-blocking. Implementations are not required to be thread-safe.

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class ServerCall.Listener<ReqT>
Callbacks for consuming incoming RPC messages.

Nested Classes
Modifier and Type	Class and Description
`static class`	`ServerCall.Listener<ReqT>` Callbacks for consuming incoming RPC messages.

Field Summary

Fields
Modifier and Type	Field and Description
`static Attributes.Key<SocketAddress>`	`REMOTE_ADDR_KEY` `Attributes.Key` for the remote address of server call attributes `attributes()`
`static Attributes.Key<SSLSession>`	`SSL_SESSION_KEY` `Attributes.Key` for the SSL session of server call attributes `attributes()`

Constructor Summary

Constructors
Constructor and Description

ServerCall()

Constructors
Constructor and Description
`ServerCall()`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`Attributes`	`attributes()` Returns properties of a single call.
`abstract void`	`close(Status status, Metadata trailers)` Close the call with the provided status.
`abstract MethodDescriptor<ReqT,RespT>`	`getMethodDescriptor()` The `MethodDescriptor` for the call.
`abstract boolean`	`isCancelled()` Returns `true` when the call is cancelled and the server is encouraged to abort processing to save resources, since the client will not be processing any further methods.
`boolean`	`isReady()` If `true`, indicates that the call is capable of sending additional messages without requiring excessive buffering internally.
`abstract void`	`request(int numMessages)` Requests up to the given number of messages from the call to be delivered to `ServerCall.Listener.onMessage(Object)`.
`abstract void`	`sendHeaders(Metadata headers)` Send response header metadata prior to sending a response message.
`abstract void`	`sendMessage(RespT message)` Send a response message.
`void`	`setCompression(String compressor)` Sets the compression algorithm for this call.
`void`	`setMessageCompression(boolean enabled)` Enables per-message compression, if an encoding type has been negotiated.

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

- Field Detail
  - REMOTE_ADDR_KEY
```
@ExperimentalApi(value="https://github.com/grpc/grpc-java/issues/1710")
public static final Attributes.Key<SocketAddress> REMOTE_ADDR_KEY
```
    Attributes.Key for the remote address of server call attributes attributes()
  - SSL_SESSION_KEY
```
@ExperimentalApi(value="https://github.com/grpc/grpc-java/issues/1710")
public static final Attributes.Key<SSLSession> SSL_SESSION_KEY
```
    Attributes.Key for the SSL session of server call attributes attributes()
- Constructor Detail
  - ServerCall
```
public ServerCall()
```
- Method Detail
  - request
```
public abstract void request(int numMessages)
```
    Requests up to the given number of messages from the call to be delivered to ServerCall.Listener.onMessage(Object). Once numMessages have been delivered no further request messages will be delivered until more messages are requested by calling this method again.
    Servers use this mechanism to provide back-pressure to the client for flow-control.
    This method is safe to call from multiple threads without external synchronizaton.
    
    Parameters:
    
    numMessages - the requested number of messages to be delivered to the listener.
  - sendHeaders
```
public abstract void sendHeaders(Metadata headers)
```
    Send response header metadata prior to sending a response message. This method may only be called once and cannot be called after calls to sendMessage(RespT) or close(io.grpc.Status, io.grpc.Metadata).
    Since Metadata is not thread-safe, the caller must not access headers after this point.
    
    Parameters:
    
    headers - metadata to send prior to any response body.
    
    Throws:
    
    IllegalStateException - if close has been called, a message has been sent, or headers have already been sent
  - sendMessage
```
public abstract void sendMessage(RespT message)
```
    Send a response message. Messages are the primary form of communication associated with RPCs. Multiple response messages may exist for streaming calls.
    
    Parameters:
    
    message - response message.
    
    Throws:
    
    IllegalStateException - if headers not sent or call is close(io.grpc.Status, io.grpc.Metadata)d
  - isReady
```
public boolean isReady()
```
    If true, indicates that the call is capable of sending additional messages without requiring excessive buffering internally. This event is just a suggestion and the application is free to ignore it, however doing so may result in excessive buffering within the call.
    This implementation always returns true.
  - close
```
public abstract void close(Status status,
                           Metadata trailers)
```
    Close the call with the provided status. No further sending or receiving will occur. If Status.isOk() is false, then the call is said to have failed.
    If no errors or cancellations are known to have occurred, then a ServerCall.Listener.onComplete() notification should be expected, independent of status. Otherwise ServerCall.Listener.onCancel() has been or will be called.
    Since Metadata is not thread-safe, the caller must not access trailers after this point.
    
    Throws:
    
    IllegalStateException - if call is already closed
  - isCancelled
```
public abstract boolean isCancelled()
```
    Returns true when the call is cancelled and the server is encouraged to abort processing to save resources, since the client will not be processing any further methods. Cancellations can be caused by timeouts, explicit cancel by client, network errors, and similar.
    This method may safely be called concurrently from multiple threads.
  - setMessageCompression
```
@ExperimentalApi(value="https://github.com/grpc/grpc-java/issues/1704")
public void setMessageCompression(boolean enabled)
```
    Enables per-message compression, if an encoding type has been negotiated. If no message encoding has been negotiated, this is a no-op. By default per-message compression is enabled, but may not have any effect if compression is not enabled on the call.
  - setCompression
```
@ExperimentalApi(value="https://github.com/grpc/grpc-java/issues/1704")
public void setCompression(String compressor)
```
    Sets the compression algorithm for this call. If the server does not support the compression algorithm, the call will fail. This method may only be called before sendHeaders(io.grpc.Metadata). The compressor to use will be looked up in the CompressorRegistry. Default gRPC servers support the "gzip" compressor.
    
    Parameters:
    
    compressor - the name of the compressor to use.
    
    Throws:
    
    IllegalArgumentException - if the compressor name can not be found.
  - attributes
```
@ExperimentalApi(value="https://github.com/grpc/grpc-java/issues/1779")
public Attributes attributes()
```
    Returns properties of a single call. This is a generic container which can contain any kind of information describing call like for example remote address, TLS information (OU etc.)
    
    Returns:
    
    Attributes container
  - getMethodDescriptor
```
public abstract MethodDescriptor<ReqT,RespT> getMethodDescriptor()
```
    The MethodDescriptor for the call.

Class ServerCall<ReqT,RespT>

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

REMOTE_ADDR_KEY

SSL_SESSION_KEY

Constructor Detail

ServerCall

Method Detail

request

sendHeaders

sendMessage

isReady

close

isCancelled

setMessageCompression

setCompression

attributes

getMethodDescriptor