Module org.eclipse.jetty.server

Package org.eclipse.jetty.server

Interface Request.Handler

All Superinterfaces:

org.eclipse.jetty.util.thread.Invocable

All Known Subinterfaces:

Handler, Handler.Collection, Handler.Container, Handler.Singleton, HandlerContainer

All Known Implementing Classes:

AbstractHandler, AbstractHandlerContainer, BufferedResponseHandler, ConditionalHandler, ConditionalHandler.Abstract, ConditionalHandler.DontHandle, ConditionalHandler.ElseNext, ConditionalHandler.Reject, ConditionalHandler.SkipNext, ConnectHandler, ContextHandler, ContextHandlerCollection, CrossOriginHandler, DebugHandler, DefaultHandler, DelayedHandler, ErrorHandler, EventsHandler, GracefulHandler, GzipHandler, Handler.Abstract, Handler.Abstract.NonBlocking, Handler.AbstractContainer, Handler.Sequence, Handler.Wrapper, HotSwapHandler, IdleTimeoutHandler, InetAccessHandler, LatencyRecordingHandler, MovedContextHandler, PathMappingsHandler, QoSHandler, ReHandlingErrorHandler, ReHandlingErrorHandler.ByHttpStatus, ResourceHandler, ResourceHandler.ResourceContext, SecuredRedirectHandler, Server, ShutdownHandler, SizeLimitHandler, SizeLimitHandler, StateTrackingHandler, StatisticsHandler, StatisticsHandler.MinimumDataRateHandler, ThreadLimitHandler, TryPathsHandler

Enclosing interface:

Request

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@ManagedObject
@FunctionalInterface
public static interface Request.Handler
extends org.eclipse.jetty.util.thread.Invocable

A handler for an HTTP request and response.

The handling typically involves reading the request content (if any) and producing a response.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	Request.Handler.AbortException	A marker Exception that can be passed the Callback.failed(Throwable) of the Callback passed in handle(Request, Response, Callback), to cause request handling to be aborted.

Nested classes/interfaces inherited from interface org.eclipse.jetty.util.thread.Invocable

org.eclipse.jetty.util.thread.Invocable.Callable, org.eclipse.jetty.util.thread.Invocable.InvocationType, org.eclipse.jetty.util.thread.Invocable.ReadyTask, org.eclipse.jetty.util.thread.Invocable.Task

Field Summary

Fields inherited from interface org.eclipse.jetty.util.thread.Invocable

__nonBlocking, NOOP

Method Summary

Modifier and Type	Method	Description
default org.eclipse.jetty.util.thread.Invocable.InvocationType	getInvocationType()
boolean	handle(Request request, Response response, org.eclipse.jetty.util.Callback callback)	Invoked to handle the passed HTTP request and response.

Method Details

handle

boolean handle(Request request,
 Response response,
 org.eclipse.jetty.util.Callback callback)
        throws Exception

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 - the HTTP request to handle

response - the HTTP response to handle

callback - the callback to complete when the handling is complete

Returns:

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.

Throws:

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.

See Also:

• Request.Handler.AbortException

getInvocationType

@ManagedAttribute("The InvocationType of this Handler")
default org.eclipse.jetty.util.thread.Invocable.InvocationType getInvocationType()

Specified by:

getInvocationType in interface org.eclipse.jetty.util.thread.Invocable