org.mdiutil.util.regex

Class RegexCollection

java.lang.Object

org.mdiutil.util.regex.RegexCollection

public class RegexCollection
extends Object

Ths class allows to specify a list of regex patterns and match a CharSequence against all the patterns. it simplifies the usage of several regex expressions against the same input.

Constructor Summary

Constructors

Constructor and Description
RegexCollection()

Method Summary

Modifier and Type	Method and Description
void	acceptUnmatchedPattern(boolean acceptUnmatchedPattern) Set if the collection accept the unmatched pattern.
void	addPattern(String name, String regex) Add a pattern for the collection of regex patterns.
void	addPattern(String name, String regex, int flags) Add a pattern for the collection of regex patterns.
void	clear() Clear the list of regex patterns.
RegexCollection	deriveCollection() Create a new RegexCollection from a previous one.
List<RegexPattern>	getOrderedPatterns() Return the ordered list of regex patterns.
Map<String,RegexPattern>	getPatterns() Return the Map of regex patterns.
boolean	isAcceptingUnmatchedPattern() Return true if the collection accept the unmatched pattern.
boolean	isEmpty() Return true if the collection is empty.
RegexMatcher	matcher(CharSequence input) Return the appropriate matcher on a CharSequence input.

Methods inherited from class java.lang.Object

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

Constructor Detail

RegexCollection

public RegexCollection()

Method Detail

deriveCollection

public RegexCollection deriveCollection()

Create a new RegexCollection from a previous one. Note that the content of the new RegexCollection will be separated from the content of the current RegexCollection, which means that if you modify this RegexCollection after calling this method, the new one will not change.

Returns:

the new collection

addPattern

public void addPattern(String name,
                       String regex)
                throws PatternSyntaxException

Add a pattern for the collection of regex patterns.

Parameters:

name - the pattern name

regex - the pattern regex

Throws:

PatternSyntaxException - If the expression's syntax is invalid

addPattern

public void addPattern(String name,
                       String regex,
                       int flags)
                throws PatternSyntaxException

Add a pattern for the collection of regex patterns.

Parameters:

name - the pattern name

regex - the pattern regex

flags - Match flags

Throws:

PatternSyntaxException - If the expression's syntax is invalid

acceptUnmatchedPattern

public void acceptUnmatchedPattern(boolean acceptUnmatchedPattern)

Set if the collection accept the unmatched pattern. It means that if no pattern in the collection has a matcher which matches the input, then the RegexMatcher.UNMATCHED instance will be returned by the matcher(java.lang.CharSequence) method. Note that by default the last pattern in the ordered list of patterns will be returned, regardless if it matches the input or not.

Parameters:

acceptUnmatchedPattern - true if the collection accept the unmatched pattern

isAcceptingUnmatchedPattern

public boolean isAcceptingUnmatchedPattern()

Return true if the collection accept the unmatched pattern. It means that if no pattern in the collection has a matcher which matches the input, then the RegexMatcher.UNMATCHED instance will be returned by the matcher(java.lang.CharSequence) method.

Returns:

true if the collection accept the unmatched pattern

clear

public void clear()

Clear the list of regex patterns.

isEmpty

public boolean isEmpty()

Return true if the collection is empty.

Returns:

true if the collection is empty

getOrderedPatterns

public List<RegexPattern> getOrderedPatterns()

Return the ordered list of regex patterns.

Returns:

the ordered list of regex patterns

getPatterns

public Map<String,RegexPattern> getPatterns()

Return the Map of regex patterns.

Returns:

the Map of regex patterns

matcher

public RegexMatcher matcher(CharSequence input)
                     throws EmptyRegexCollectionException

Return the appropriate matcher on a CharSequence input.

Algorithm

The class will iterate from the first specified pattern to the last one. The default behavior is:

• If a pattern match, the iteration stops and the associated RegexMatcher will be returned
• If the last pattern does not match, the iteration stops on the associated RegexMatcher

Accepting the unmatched pattern

If the isAcceptingUnmatchedPattern() returns true, then the behavior will be:

• If a pattern match, the iteration stops and the associated RegexMatcher will be returned
• If the last pattern does not match, the iteration stops on the RegexMatcher.UNMATCHED matcher

Example

For example:

   RegexCollection collection = new RegexCollection();
   collection.addPattern("number", "\\d+");
   collection.addPattern("letters", "[A-Za-z]+");

   RegexMatcher matcher = collection.matcher("156");
   String name = matcher.getPatternName(); // return "number"
   boolean matches = matcher.matches(); // return true

   matcher = collection.matcher("Slayer");
   name = matcher.getPatternName(); // return "letters"
   matches = matcher.matches(); // return true

   matcher = collection.matcher("1349 band");
   name = matcher.getPatternName(); // return "letters"
   matches = matcher.matches(); // return false
 

Parameters:

input - the input

Returns:

the appropriate matcher

Throws:

EmptyRegexCollectionException - if the RegexCollection is empty (has no Patterns)