com.google.gdata.util.parser

Class Action<T,U extends T>

java.lang.Object

com.google.gdata.util.parser.Parser<U>

com.google.gdata.util.parser.Action<T,U>

Type Parameters:

T -

U -

public class Action<T,U extends T>
extends Parser<U>

Actions are fired when their subject parser matches. The Callback class is passed the matching portion of the parse text. Note that the Action parser wraps around its subject. It will parse exactly the same text that its subject parser parses. Parser p = Chset.ALPHA.plus().action(new Callback() { public void handle(char[] buf, int start, int end, Object data) { StringBuffer str = (StringBuffer) data; str.delete(0, str.length()); str.append(buf, start, end - start); } }); StringBuffer buf = new StringBuffer(); p.parse("a") -> matches "a", buf == "a" p.parse("abcde") -> matches "abcde", buf == "abcde" p.parse("a0") -> matches "a", buf == "a" p.parse("0") -> no match, buf unchanged

See Also:

Callback, Parser

Field Summary

Fields inherited from class com.google.gdata.util.parser.Parser

NO_MATCH

Constructor Summary

Constructors

Constructor and Description
Action(Parser<T> subject, Callback<U> callback) Class constructor.

Method Summary

Methods

Modifier and Type	Method and Description
int	parse(char[] buf, int start, int end, U data) Matches the subject parser against the current state of the buffer being parsed.

Methods inherited from class com.google.gdata.util.parser.Parser

action, alternative, difference, intersection, list, optional, parse, parse, parse, plus, repeat, repeat, sequence, sequence, sequence, sequence, star

Methods inherited from class java.lang.Object

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

Constructor Detail

Action

public Action(Parser<T> subject,
      Callback<U> callback)

Class constructor.

Parameters:

subject - The Parser that this action is wrapping around.

callback - The Callback that will be invoked if the subject parser returns a result different than NO_MATCH.

Method Detail

parse

public int parse(char[] buf,
        int start,
        int end,
        U data)

Matches the subject parser against the current state of the buffer being parsed. If the subject parser hits (returns a result other than NO_MATCH), callback.handle will be invoked and passed the matching region of the parse buffer.

Specified by:

parse in class Parser<U extends T>

Parameters:

buf - The character array to match against.

start - The start offset of data within the character array to match against.

end - The end offset of data within the character array to match against.

data - User defined object that is passed to Callback.handle when an Action fires.

See Also:

Parser.parse(char[], int, int, T)