Class ThreadLimitHandler

java.lang.Object
All Implemented Interfaces:
Handler, Handler.Container, Handler.Singleton, Request.Handler, org.eclipse.jetty.util.component.Container, org.eclipse.jetty.util.component.Destroyable, org.eclipse.jetty.util.component.Dumpable, org.eclipse.jetty.util.component.Dumpable.DumpableContainer, org.eclipse.jetty.util.component.LifeCycle, org.eclipse.jetty.util.thread.Invocable

public class ThreadLimitHandler extends ConditionalHandler.Abstract

Handler to limit the number of concurrent threads per remote IP address, for DOS protection.

ThreadLimitHandler applies a limit to the number of threads that can be used simultaneously per remote IP address.

The handler makes a determination of the remote IP separately to any that may be made by the ForwardedRequestCustomizer or similar:

  • This handler will use only a single style of forwarded header. This is on the assumption that a trusted local proxy will produce only a single forwarded header and that any additional headers are likely from untrusted client side proxies.
  • If multiple instances of a forwarded header are provided, this handler will use the right-most instance, which will have been set from the trusted local proxy

Requests in excess of the limit will be asynchronously suspended until a thread is available.