dk.netarkivet.viewerproxy
Class CommandResolver

java.lang.Object
  dk.netarkivet.viewerproxy.CommandResolver

All Implemented Interfaces:

URIResolver, URIResolverHandler

Direct Known Subclasses:

GetDataResolver, HTTPControllerServer, UnknownCommandResolver

public abstract class CommandResolver
extends java.lang.Object
implements URIResolverHandler, URIResolver

An abstract superclass for URIResolvers that handle commands given to the server host (http://<>/<>/<>=<>*

Field Summary

protected URIResolver	ur The URI resolver which is wrapped, and which handles all non-command URIs
static java.lang.String	VIEWERPROXY_COMMAND_NAME Fake host used as hostname when doing commands.

Fields inherited from interface dk.netarkivet.viewerproxy.URIResolver

NOT_FOUND

Constructor Summary

CommandResolver(URIResolver ur)
Constructor which sets the next resolver in the chain.

Method Summary

protected abstract boolean	executeCommand(Request request, Response response) Abstract method for parsing of the URL and delegating to relevant methods.
protected static boolean	isCommandHostRequest(Request request) Returns true if the request specifies the host that we're running on.
int	lookup(Request request, Response response) Parses the given URI and executes commands for all command URLs.
void	setURIResolver(URIResolver ur) Change the URI resolver which handles URIs that we don't handle here.

Methods inherited from class java.lang.Object

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

Field Detail

ur

protected URIResolver ur

The URI resolver which is wrapped, and which handles all non-command URIs

VIEWERPROXY_COMMAND_NAME

public static final java.lang.String VIEWERPROXY_COMMAND_NAME

Fake host used as hostname when doing commands.

See Also:

Constant Field Values

Constructor Detail

CommandResolver

public CommandResolver(URIResolver ur)

Constructor which sets the next resolver in the chain.

Parameters:

ur - The URIResolver that handles URIs that are not handled by this resolver.

Method Detail

setURIResolver

public final void setURIResolver(URIResolver ur)

Change the URI resolver which handles URIs that we don't handle here.

Specified by:

setURIResolver in interface URIResolverHandler

Parameters:

ur - The URI resolver to handle unhandled URIs.

Throws:

ArgumentNotValid - if either argument is null.

lookup

public final int lookup(Request request,
                        Response response)

Parses the given URI and executes commands for all command URLs. The possible commands are of the form http://<>/<>?<>=<>* where command and param are defined in the subclass. If uri is none of these, the uri and response are forwarded to the wrapped URI resolver.

Specified by:

lookup in interface URIResolver

Parameters:

request - The HTTP request we are working on

response - HTTP response to generate effect on or to forward

Returns:

response code

executeCommand

protected abstract boolean executeCommand(Request request,
                                          Response response)

Abstract method for parsing of the URL and delegating to relevant methods. This should start by calling isCommandHostRequest.

Parameters:

request - The request to check

response - The response to give command results to if it is a command

Returns:

Whether this was a command URL

isCommandHostRequest

protected static boolean isCommandHostRequest(Request request)

Returns true if the request specifies the host that we're running on. Alternative specifications such as 'localhost' or '127.0.0.1' or an actual IP of this machine are not considered command hosts. Local hosts would only be command hosts if we happen to get a request from a browser running on this machine.

Parameters:

request - An HTTP request.

Returns:

True if the HTTP request specifies a URI that indicates this machine, false otherwise.