org.eclipse.jetty.util

Class SocketAddressResolver

java.lang.Object

org.eclipse.jetty.util.SocketAddressResolver

public class SocketAddressResolver
extends Object

Creates asynchronously SocketAddress instances, returning them through a Promise, in order to avoid blocking on DNS lookup.

InetSocketAddress.InetSocketAddress(String, int) attempts to perform a DNS resolution of the host name, and this may block for several seconds. This class creates the InetSocketAddress in a separate thread and provides the result through a Promise, with the possibility to specify a timeout for the operation.

Example usage:

 SocketAddressResolver resolver = new SocketAddressResolver(executor, scheduler);
 resolver.resolve("www.google.com", 80, new Promise<SocketAddress>()
 {
     public void succeeded(SocketAddress result)
     {
         // The address was resolved
     }

     public void failed(Throwable failure)
     {
         // The address resolution failed
     }
 });
 

Constructor Summary

Constructors

Constructor and Description
SocketAddressResolver(Executor executor, Scheduler scheduler, long timeout) Creates a new instance with the given executor (to perform DNS resolution in a separate thread), the given scheduler (to cancel the operation if it takes too long) and the given timeout, in milliseconds.

Method Summary

Methods

Modifier and Type	Method and Description
Executor	getExecutor()
Scheduler	getScheduler()
long	getTimeout()
protected void	resolve(String host, int port, long timeout, Promise<SocketAddress> promise) Resolves the given host and port, returning a SocketAddress through the given Promise with the given timeout.
void	resolve(String host, int port, Promise<SocketAddress> promise) Resolves the given host and port, returning a SocketAddress through the given Promise with the default timeout.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SocketAddressResolver

public SocketAddressResolver(Executor executor,
                     Scheduler scheduler,
                     long timeout)

Creates a new instance with the given executor (to perform DNS resolution in a separate thread), the given scheduler (to cancel the operation if it takes too long) and the given timeout, in milliseconds.

Parameters:

executor - the thread pool to use to perform DNS resolution in pooled threads

scheduler - the scheduler to schedule tasks to cancel DNS resolution if it takes too long

timeout - the timeout, in milliseconds, for the DNS resolution to complete

Method Detail

getExecutor

public Executor getExecutor()

getScheduler

public Scheduler getScheduler()

getTimeout

public long getTimeout()

resolve

public void resolve(String host,
           int port,
           Promise<SocketAddress> promise)

Resolves the given host and port, returning a SocketAddress through the given Promise with the default timeout.

Parameters:

host - the host to resolve

port - the port of the resulting socket address

promise - the callback invoked when the resolution succeeds or fails

See Also:

resolve(String, int, long, Promise)

resolve

protected void resolve(String host,
           int port,
           long timeout,
           Promise<SocketAddress> promise)

Resolves the given host and port, returning a SocketAddress through the given Promise with the given timeout.

Parameters:

host - the host to resolve

port - the port of the resulting socket address

timeout - the timeout, in milliseconds, for the DNS resolution to complete

promise - the callback invoked when the resolution succeeds or fails