com.florianingerl.util.regex

Class Pattern.CustomNode

java.lang.Object

com.florianingerl.util.regex.Pattern.CustomNode

Enclosing class:

Pattern

public abstract static class Pattern.CustomNode
extends Object

Base class for plugins into the regex engine. A Regular Expression is compiled into a chained sequence of nodes, each node matching the input character sequence against its pattern and then asking its next node to do the same. By extending this class and overriding the match method, you thus provide a plugin into the regex engine that you can install via Pattern.installPlugin(String, Class).

Constructor Summary

Constructors

Constructor and Description
CustomNode()

Method Summary

Modifier and Type	Method and Description
protected abstract boolean	isDeterministic()
protected abstract boolean	isMaxValid() Says whether this node can match arbitrary many characters This is used by Lookbehinds.
protected abstract boolean	match(Matcher matcher, int i, CharSequence seq) Matches the input character sequence against this node's pattern.
protected boolean	matchNext(Matcher matcher, int i, CharSequence seq)
protected abstract int	maxLength() Returns the maximum number of characters that this node matches.
protected abstract int	minLength() Returns the minimum number of characters that this node matches.
protected Object	retrieveData(Matcher matcher) Retrieves the data stored in matcher.
protected void	storeData(Matcher matcher, Object data) Stores some search data in matcher.

Methods inherited from class java.lang.Object

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

Constructor Detail

CustomNode

public CustomNode()

Method Detail

match

protected abstract boolean match(Matcher matcher,
                                 int i,
                                 CharSequence seq)

Matches the input character sequence against this node's pattern. The character sequence seq is matched against this node's pattern, where the characters 0 to i-1 in seq have already been matched by previous nodes. If this node matches say n characters, you have to call matchNext(matcher, i+n, seq). In case matchNext returns true, this method usually should also return true. In case matchNext returns false, this node might try to match something different with possibly either more or less characters and then call matchNext again. Then this node would be a backtracking crossroad. Or this node might restore the state of matcher and return false.

See Also:

matchNext(Matcher, int, CharSequence)

matchNext

protected boolean matchNext(Matcher matcher,
                            int i,
                            CharSequence seq)

retrieveData

protected Object retrieveData(Matcher matcher)

Retrieves the data stored in matcher.

See Also:

storeData(Matcher, Object)

storeData

protected void storeData(Matcher matcher,
                         Object data)

Stores some search data in matcher. Instances of the Pattern class and all its nodes are completely stateless allowing concurrent use. All state of the regex engine is therefore stored in matcher, which is what this method allows subclasses to do.

Parameters:

matcher - The Matcher in which to store the data.

data - The data to store in matcher.

See Also:

retrieveData(Matcher)

minLength

protected abstract int minLength()

Returns the minimum number of characters that this node matches.

Returns:

The minimum number of characters that this node matches.

maxLength

protected abstract int maxLength()

Returns the maximum number of characters that this node matches.

Returns:

The maximum number of characters that this node matches.

isMaxValid

protected abstract boolean isMaxValid()

Says whether this node can match arbitrary many characters This is used by Lookbehinds. Only Lookbehinds with a valid maximum length are allowed.

Returns:

false, if this node can match arbitrary many characters.

isDeterministic

protected abstract boolean isDeterministic()