org.htmlunit.cyberneko

Class HTMLNamedEntitiesParser

java.lang.Object

org.htmlunit.cyberneko.HTMLNamedEntitiesParser

public final class HTMLNamedEntitiesParser
extends Object

This is a very specialized class for recognizing HTML named entities with the ability to look them up in stages. It is stateless and hence memory friendly. Additionally, it is not generated code rather it sets itself up from a file at first use and stays fixed from now on. Technically, it is not a parser anymore, because it does not have a state that matches the HTML standard: 12.2.5.72 Character reference state

Because it is stateless, it delegates the state handling to the user in the sense of how many characters one saw and when to stop doing things.

Author:

René Schwietzke, Ronald Brill

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	HTMLNamedEntitiesParser.RootState This is our initial state and has a special optimization applied.
static class	HTMLNamedEntitiesParser.State Our "level" in the treeish structure that keeps its static state and the next level underneath.

Method Summary

Modifier and Type	Method and Description
static HTMLNamedEntitiesParser	get() Returns the singleton.
HTMLNamedEntitiesParser.State	lookup(int character, HTMLNamedEntitiesParser.State state) Pseudo parses and entity character by character.
HTMLNamedEntitiesParser.State	lookup(String entityName) Utility method, mostly for testing, that allows us to look up and entity from a string instead from single characters.
String	lookupEntityRefFor(String key)

Methods inherited from class java.lang.Object

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

Method Detail

get

public static HTMLNamedEntitiesParser get()

Returns the singleton. The singleton is stateless and can safely be used in a multi-threaded context.

Returns:

the singleton instance of the parser, can never be null

lookup

public HTMLNamedEntitiesParser.State lookup(String entityName)

Utility method, mostly for testing, that allows us to look up and entity from a string instead from single characters.

Parameters:

entityName - the entity to look up

Returns:

a state that resembles the result, will never be null

lookup

public HTMLNamedEntitiesParser.State lookup(int character,
                                            HTMLNamedEntitiesParser.State state)

Pseudo parses and entity character by character. We assume that we get presented with the chars after the starting ampersand. This parser does not supported unicode entities, hence this has to be handled differently.

Parameters:

character - the next character, should not be the ampersand ever

state - the last known state or null in case we start to parse

Returns:

the current state, which might be a valid final result, see HTMLNamedEntitiesParser.State

lookupEntityRefFor

public String lookupEntityRefFor(String key)

Returns:

the entity ref for the given key (usually a single char) or null