sunlabs.brazil.handler

Class RePollHandler

java.lang.Object

java.lang.Thread

sunlabs.brazil.handler.PollHandler

sunlabs.brazil.handler.RePollHandler

All Implemented Interfaces:

java.lang.Runnable, Handler

public class RePollHandler
extends PollHandler

Do regsub processing on content to extract properties.

Properties:

encoding

The character set encoding to use when converting the request results to a string. Defaults to the default encoding.

prepend

The string to prepend to all properties. Extracted properties will contain the the "re" token as an additional prefix.

re

the list of "re" tokens to process in order. Each "re" token has the following attributes:

re.exp

The regular expression to search for.

re.sub

The regular expression substitution pattern. If 'E' is specified, the substitution is done after the extraction.

re.names

A white-space delimited set of tokens to use instead of numerical indices to name the properties. The first name in the list names the entire match, the remaining names name the sub-expressions. If there are more properties extracted than names provided, the "left over" properties will have numerical indeces. This implies 'E'.

If the name "X" is used, no property will be extracted for that match.

re.key

The index of the sub-match (starting at 1) that will be used to name the row number portion of the property name instead of a counter. This is useful if one of the sub-matches will be unique for each matching pattern. This option is ignored if the "O" flag is specified, as there will be only one match so no "key" is required.

re.flags

One or more ASCII flags to control how this "re" is processed. Consists of one or more of The following (defaults to "SFE"):. Characters not on this list are ignored.

• E Extract current result into server properties. See the rules for naming the properties, below. At least one regular expression Must have an "E" flag.
• F Process if previous "RE" failed.
• I Ignore case in expression
• O only do one substitution or extraction, not all
• R Reset content to original before proceeding Otherwise, the result of the previous substitution (if any) is used.
• S Process if previous "RE" succeeded

First remote content is obtained. Then each regular expression token is processed in turn for the purpose of extracting portions of that content into server properties. [re].sub is used to transform the content before attempting to extract properties.

Content is extracted into the following properties.

prepend.[re].[m].[n]

The result of the expression associated with token "re". 'n' is the sub-expression number, and 'm' is the match number, both starting at '0'. If the 'O' flag is specified, there can only be one value for 'm', so it is not included (e.g. the name of the property will be "prepend.[re].[n]).

prepend.[re].matches

A list of matches, that may be used as an iterator to foreach.

prepend.[re].subexpressions

The number of sub-expressions associated with [re].

Version:

%V% RePollHandler.java 2.2

Author:

Stephen Uhler

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	RePollHandler.Extract A "bag" to store regular expression extraction instructions

Nested classes/interfaces inherited from class java.lang.Thread

java.lang.Thread.State, java.lang.Thread.UncaughtExceptionHandler

Field Summary

Fields inherited from class sunlabs.brazil.handler.PollHandler

interval, post, url

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

Constructors

Constructor and Description
RePollHandler()

Method Summary

Modifier and Type	Method and Description
void	fillProps(java.util.Properties props, HttpRequest target) Fill the properties by extracting fields from the response.
boolean	init(Server server, java.lang.String prefix) Set up the initial configuration, and kick off a thread to periodically fetch the url.
void	processText(java.util.Properties props, java.lang.String data) Process the contents as a string through the regular expressions.
boolean	respond(Request request) Allow The url and post data (if any) to be changed.

Methods inherited from class sunlabs.brazil.handler.PollHandler

run

Methods inherited from class java.lang.Thread

activeCount, checkAccess, clone, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Constructor Detail

RePollHandler

public RePollHandler()

Method Detail

init

public boolean init(Server server,
                    java.lang.String prefix)

Description copied from class: PollHandler

Set up the initial configuration, and kick off a thread to periodically fetch the url.

Specified by:

init in interface Handler

Overrides:

init in class PollHandler

Parameters:

server - The HTTP server that created this Handler. Typical Handlers will use Server.props to obtain run-time configuration information.

prefix - The handlers name. The string this Handler may prepend to all of the keys that it uses to extract configuration information from Server.props. This is set (by the Server and ChainHandler) to help avoid configuration parameter namespace collisions.

Returns:

true if this Handler initialized successfully, false otherwise. If false is returned, this Handler should not be used.

respond

public boolean respond(Request request)

Allow The url and post data (if any) to be changed. A query parameter of the form "url=xxx" replaces the current url. A query parameter of the form "post=xxx" replaces the post data, if any was initially defined.

Specified by:

respond in interface Handler

Overrides:

respond in class PollHandler

Parameters:

request - The Request object that represents the HTTP request.

Returns:

true if the request was handled. A request was handled if a response was supplied to the client, typically by calling Request.sendResponse() or Request.sendError.

fillProps

public void fillProps(java.util.Properties props,
                      HttpRequest target)
               throws java.io.IOException

Fill the properties by extracting fields from the response. This overrides fillProps.

Overrides:

fillProps in class PollHandler

Throws:

java.io.IOException

processText

public void processText(java.util.Properties props,
                        java.lang.String data)

Process the contents as a string through the regular expressions. This is public, and separate from fillProps to make unit testing easier.