Top Description Inners Fields Constructors Methods
org.eclipse.jetty.server.handler

public Class GracefulHandler

extends Wrapper
implements Graceful
Class Inheritance
All Implemented Interfaces
org.eclipse.jetty.util.component.Graceful
Imports
java.util.concurrent.CompletableFuture, java.util.concurrent.atomic.LongAdder, org.eclipse.jetty.http.HttpStatus, org.eclipse.jetty.server.Handler, .Request, .Response, org.eclipse.jetty.util.Callback, .CountingCallback, org.eclipse.jetty.util.annotation.ManagedAttribute, org.eclipse.jetty.util.component.Graceful, org.slf4j.Logger, .LoggerFactory

Handler to track active requests and allow them to gracefully complete.

Nested and Inner Type Summary

Modifier and TypeClass and Description
private class

Field Summary

Modifier and TypeField and Description
private final LongAdder
private final Graceful.Shutdown
private static final Logger

Constructor Summary

AccessConstructor and Description
public
public

Method Summary

Modifier and TypeMethod and Description
public long
public boolean
handle(Request
the HTTP request to handle
request
,
Response
the HTTP response to handle
response
,
Callback
the callback to complete when the handling is complete
callback
)

Overrides org.eclipse.jetty.server.Handler.Wrapper.handle.

Implements org.eclipse.jetty.server.Request.Handler.handle.

Invoked to handle the passed HTTP request and response.

public boolean

Returns:

whether the graceful shutdown has been initiated
isShutdown
()

Implements org.eclipse.jetty.util.component.Graceful.isShutdown.

Flag indicating that Graceful shutdown has been initiated.
public CompletableFuture<Void>
shutdown()

Implements org.eclipse.jetty.util.component.Graceful.shutdown.

Shutdown the component.
Inherited from org.eclipse.jetty.server.Handler.Wrapper:
getHandlergetInvocationTypesetHandler

Field Detail

_requestsback to summary
private final LongAdder _requests
_shutdownback to summary
private final Graceful.Shutdown _shutdown
LOGback to summary
private static final Logger LOG

Hides org.eclipse.jetty.server.Handler.Abstract.LOG.

Constructor Detail

GracefulHandlerback to summary
public GracefulHandler()
GracefulHandlerback to summary
public GracefulHandler(Handler handler)

Method Detail

getCurrentRequestCountback to summary
public long getCurrentRequestCount()
Annotations
@ManagedAttribute:number of requests being currently handled
handleback to summary
public boolean handle(Request request, Response response, Callback callback) throws Exception

Overrides org.eclipse.jetty.server.Handler.Wrapper.handle.

Implements org.eclipse.jetty.server.Request.Handler.handle.

Doc from org.eclipse.jetty.server.Request.Handler.handle.

Invoked to handle the passed HTTP request and response.

The request is accepted by returning true, then handling must be concluded by completing the passed callback. The handling may be asynchronous, i.e. this method may return true and complete the given callback later, possibly from a different thread. If this method returns false, then the callback must not be invoked and any mutation on the response reversed.

Exceptions thrown by this method may be subsequently handled by an error Request.Handler, if present, otherwise a default HTTP 500 error is generated and the callback completed while writing the error response.

The simplest implementation is:

public boolean handle(Request request, Response response, Callback callback)
{
    callback.succeeded();
    return true;
}

A HelloWorld implementation is:

public boolean handle(Request request, Response response, Callback callback)
{
    response.write(true, ByteBuffer.wrap("Hello World\n".getBytes(StandardCharsets.UTF_8)), callback);
    return true;
}
Parameters
request:Request

the HTTP request to handle

response:Response

the HTTP response to handle

callback:Callback

the callback to complete when the handling is complete

Returns:boolean

True if and only if the request will be handled, a response generated and the callback eventually called. This may occur within the scope of the call to this method, or asynchronously some time later. If false is returned, then this method must not generate a response, nor complete the callback.

Annotations
@Override
Exceptions
Exception:
if there is a failure during the handling. Catchers cannot assume that the callback will be called and thus should attempt to complete the request as if a false had been returned.
isShutdownback to summary
public boolean isShutdown()

Implements org.eclipse.jetty.util.component.Graceful.isShutdown.

Flag indicating that Graceful shutdown has been initiated.

Returns:boolean

whether the graceful shutdown has been initiated

Annotations
@Override
See Also
Graceful
shutdownback to summary
public CompletableFuture<Void> shutdown()

Implements org.eclipse.jetty.util.component.Graceful.shutdown.

Doc from org.eclipse.jetty.util.component.Graceful.shutdown.

Shutdown the component. When this method returns, the component should not accept any new load.

Returns:CompletableFuture<Void>

A future that is completed once all load on the component is completed

Annotations
@Override
org.eclipse.jetty.server.handler back to summary

private Class GracefulHandler.ShutdownTrackingCallback

extends CountingCallback
Class Inheritance

Field Summary

Modifier and TypeField and Description
pack-priv final Request
pack-priv final Response

Constructor Summary

AccessConstructor and Description
public
ShutdownTrackingCallback(Request request, Response response, Callback callback)

Method Summary

Modifier and TypeMethod and Description
public void
Inherited from org.eclipse.jetty.util.CountingCallback:
failedsucceededtoString

Field Detail

requestback to summary
pack-priv final Request request
responseback to summary
pack-priv final Response response

Constructor Detail

ShutdownTrackingCallbackback to summary
public ShutdownTrackingCallback(Request request, Response response, Callback callback)

Method Detail

completedback to summary
public void completed()

Overrides org.eclipse.jetty.util.Callback.Nested.completed.

Implements org.eclipse.jetty.util.Callback.Completing.completed.

Annotations
@Override