org.pf.text
Class StringPattern

java.lang.Object
  org.pf.text.AStringFilter
      org.pf.text.StringPattern

All Implemented Interfaces:

java.io.Serializable, IObjectFilter, StringFilter

public class StringPattern
extends AStringFilter
implements java.io.Serializable

This class provides services for checking strings against string-patterns. Currently it supports the wildcards
'*' for any number of any character and
'?' for any single character.

The API is very simple:

There are two class methods match() and matchIgnoreCase().
Example:
StringPattern.match( 'Hello World", "H* W*" ) ; --> evaluates to true
StringPattern.matchIgnoreCase( 'StringPattern", "str???pat*" ) ; --> evaluates to true

To be compatible with most pattern engines this class also supports that the multi-char wildcard '*' matches empty string. By default it doesn't ! To switch on this behaviour call
pattern.multiCharWildcardMatchesEmptyString(true);
If this option is set to true, the following example returns true, otherwise it would return false:

 StringPattern pattern = new StringPattern( "Fred*" ) ;
 pattern.multiCharWildcardMatchesEmptyString(true);
 return pattern.matches( "Fred" ) ; // <== returns true
 

It is also possible to instantiate new pattern object by using the static create() methods rather than the constructors. These methods will create new patterns that have the multiCharWildcardMatchesEmptyString option initialized to true.

Version:

2.6

Author:

Manfred Duchrow

See Also:

Serialized Form

Constructor Summary

StringPattern(java.lang.String pattern)
Initializes the new instance with the string pattern.

StringPattern(java.lang.String pattern, boolean ignoreCase)
Initializes the new instance with the string pattern and the selection, if case should be ignored when comparing characters.

StringPattern(java.lang.String pattern, boolean ignoreCase, char digitWildcard)
Initializes the new instance with the string pattern and the selection, if case should be ignored when comparing characters plus a wildcard character for digits.

StringPattern(java.lang.String pattern, char digitWildcard)
Initializes the new instance with the string pattern and a digit wildcard character.

Method Summary

static boolean	containsWildcard(java.lang.String aString) Returns true if the given string contains a single or multi character wildcard.
StringPattern	copy() Returns a copy of this pattern.
static StringPattern	create(java.lang.String pattern) Returns a new instance with the string pattern.
static StringPattern	create(java.lang.String pattern, boolean ignoreCase) Returns a new instance with the string pattern and the selection, if case should be ignored when comparing characters.
static StringPattern	create(java.lang.String pattern, boolean ignoreCase, char digitWildcard) Returns a new instance with the string pattern and the selection, if case should be ignored when comparing characters plus a wildcard character for digits.
static StringPattern	create(java.lang.String pattern, char digitWildcard) Returns anew instance with the string pattern and a digit wildcard character.
boolean	equals(java.lang.Object obj) Returns true if the given object is equal to the receiver.
static char	getDefaultMultiCharWildcard() Returns the character that is used to specify any number of any character.
static char	getDefaultSingleCharWildcard() Returns the character that is used to specify any single character.
boolean	getIgnoreCase() Returns whether or not the pattern matching ignores upper and lower case
char	getMultiCharWildcard() Returns the wildcard character that is used as placeholder for zero to many occurances of any character(s).
java.lang.String	getPattern() Returns the pattern as string.
char	getSingleCharWildcard() Returns the wildcard character that is used as placeholder for a single occurance of any character.
int	hashCode() Returns a hash code value for the object.
boolean	hasWildcard() Returns true if the pattern contains any '*' or '?'
static boolean	match(java.lang.String probe, java.lang.String pattern) Returns true, if the given probe string matches the given pattern.
boolean	matches(java.lang.String probe) Tests if a specified string matches the pattern.
static boolean	matchIgnoreCase(java.lang.String probe, java.lang.String pattern) Returns true, if the given probe string matches the given pattern.
boolean	multiCharWildcardMatchesEmptyString() Returns true, if this StringPattern allows empty strings at the position of the multi character wildcard ('*').
void	multiCharWildcardMatchesEmptyString(boolean newValue) sets whether or not this StringPattern allows empty strings at the position of the multi character wildcard ('*').
java.lang.String[]	reject(java.lang.String[] strings) Returns an array containing all of the given strings that do NOT match this pattern.
java.lang.String[]	select(java.lang.String[] strings) Returns an array containing all of the given strings that match this pattern.
void	setDigitWildcardChar(char digitWildcard) Sets the given character as a wildcard character in this pattern to match only digits ('0'-'9').
void	setIgnoreCase(boolean newValue) Sets whether the pattern matching should ignore case or not
void	setMultiCharWildcard(char newValue) Sets the wildcard character that is used as placeholder for zero to many occurances of any character(s).
void	setPattern(java.lang.String newValue) Sets the pattern to a new value
void	setSingleCharWildcard(char newValue) Sets the wildcard character that is used as placeholder for a single occurance of any character.
java.lang.String	toString() Returns the pattern string.

Methods inherited from class org.pf.text.AStringFilter

matches

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

StringPattern

public StringPattern(java.lang.String pattern,
                     boolean ignoreCase)

Initializes the new instance with the string pattern and the selection, if case should be ignored when comparing characters.

Parameters:

pattern - The pattern to check against ( May contain '*' and '?' wildcards )

ignoreCase - Definition, if case sensitive character comparison or not.

See Also:

create(String, boolean)

StringPattern

public StringPattern(java.lang.String pattern)

Initializes the new instance with the string pattern. The default is case sensitive checking.

As an alternative see also StringPattern.create() method.

Parameters:

pattern - The pattern to check against ( May contain '*' and '?' wildcards )

See Also:

create(String)

StringPattern

public StringPattern(java.lang.String pattern,
                     char digitWildcard)

Initializes the new instance with the string pattern and a digit wildcard character. The default is case sensitive checking.

Parameters:

pattern - The pattern to check against ( May contain '*', '?' wildcards and the digit wildcard )

digitWildcard - A wildcard character that stands as placeholder for digits

See Also:

create(String, char)

StringPattern

public StringPattern(java.lang.String pattern,
                     boolean ignoreCase,
                     char digitWildcard)

Initializes the new instance with the string pattern and the selection, if case should be ignored when comparing characters plus a wildcard character for digits.

Parameters:

pattern - The pattern to check against ( May contain '*' and '?' wildcards )

ignoreCase - Definition, if case sensitive character comparison or not.

digitWildcard - A wildcard character that stands as placeholder for digits

See Also:

create(String, boolean, char)

Method Detail

getIgnoreCase

public boolean getIgnoreCase()

Returns whether or not the pattern matching ignores upper and lower case

setIgnoreCase

public void setIgnoreCase(boolean newValue)

Sets whether the pattern matching should ignore case or not

getPattern

public java.lang.String getPattern()

Returns the pattern as string.

setPattern

public void setPattern(java.lang.String newValue)

Sets the pattern to a new value

getSingleCharWildcard

public char getSingleCharWildcard()

Returns the wildcard character that is used as placeholder for a single occurance of any character.

setSingleCharWildcard

public void setSingleCharWildcard(char newValue)

Sets the wildcard character that is used as placeholder for a single occurance of any character.

getMultiCharWildcard

public char getMultiCharWildcard()

Returns the wildcard character that is used as placeholder for zero to many occurances of any character(s).

setMultiCharWildcard

public void setMultiCharWildcard(char newValue)

Sets the wildcard character that is used as placeholder for zero to many occurances of any character(s).

multiCharWildcardMatchesEmptyString

public boolean multiCharWildcardMatchesEmptyString()

Returns true, if this StringPattern allows empty strings at the position of the multi character wildcard ('*').

The default value is false.

multiCharWildcardMatchesEmptyString

public void multiCharWildcardMatchesEmptyString(boolean newValue)

sets whether or not this StringPattern allows empty strings at the position of the multi character wildcard ('*').

The default value is false.

create

public static StringPattern create(java.lang.String pattern)

Returns a new instance with the string pattern. The default is case sensitive checking.
The option multiCharWildcardMatchesEmptyString will be initialized to true.

Parameters:

pattern - The pattern to check against ( May contain '*' and '?' wildcards )

create

public static StringPattern create(java.lang.String pattern,
                                   boolean ignoreCase)

Returns a new instance with the string pattern and the selection, if case should be ignored when comparing characters.
The option multiCharWildcardMatchesEmptyString will be initialized to true.

Parameters:

pattern - The pattern to check against ( May contain '*' and '?' wildcards )

ignoreCase - Definition, if case sensitive character comparison or not.

create

public static StringPattern create(java.lang.String pattern,
                                   char digitWildcard)

Returns anew instance with the string pattern and a digit wildcard character. The default is case sensitive checking.
The option multiCharWildcardMatchesEmptyString will be initialized to true.

Parameters:

pattern - The pattern to check against ( May contain '*', '?' wildcards and the digit wildcard )

digitWildcard - A wildcard character that stands as placeholder for digits

create

public static StringPattern create(java.lang.String pattern,
                                   boolean ignoreCase,
                                   char digitWildcard)

Returns a new instance with the string pattern and the selection, if case should be ignored when comparing characters plus a wildcard character for digits.
It is also configured to match the wildcard '*' to empty strings.

Example:
StringPattern.create( "*London*Eye#", true, '#' ).matches( "londonEYE8" ) ==> true

Parameters:

pattern - The pattern to check against ( May contain '*' and '?' wildcards )

ignoreCase - Definition, if case sensitive character comparison or not.

digitWildcard - A wildcard character that stands as placeholder for digits

match

public static boolean match(java.lang.String probe,
                            java.lang.String pattern)

Returns true, if the given probe string matches the given pattern.
The character comparison is done case sensitive.

Parameters:

probe - The string to check against the pattern.

pattern - The patter, that probably contains wildcards ( '*' or '?' )

matchIgnoreCase

public static boolean matchIgnoreCase(java.lang.String probe,
                                      java.lang.String pattern)

Returns true, if the given probe string matches the given pattern.
The character comparison is done ignoring upper/lower-case.

Parameters:

probe - The string to check against the pattern.

pattern - The patter, that probably contains wildcards ( '*' or '?' )

getDefaultMultiCharWildcard

public static char getDefaultMultiCharWildcard()

Returns the character that is used to specify any number of any character. The default is '*'.

getDefaultSingleCharWildcard

public static char getDefaultSingleCharWildcard()

Returns the character that is used to specify any single character. The default is '?'.

containsWildcard

public static boolean containsWildcard(java.lang.String aString)

Returns true if the given string contains a single or multi character wildcard. Of course this checks only the default wildcard characters.

Parameters:

aString - The string to check for wildcard characters

matches

public boolean matches(java.lang.String probe)

Tests if a specified string matches the pattern.

Specified by:

matches in interface StringFilter

Parameters:

probe - The string to compare to the pattern

Returns:

true if and only if the probe matches the pattern, false otherwise.

select

public java.lang.String[] select(java.lang.String[] strings)

Returns an array containing all of the given strings that match this pattern.

Parameters:

strings - The strings to be matched against this pattern

reject

public java.lang.String[] reject(java.lang.String[] strings)

Returns an array containing all of the given strings that do NOT match this pattern.

Parameters:

strings - The strings to be matched against this pattern

toString

public java.lang.String toString()

Returns the pattern string.

Overrides:

toString in class java.lang.Object

See Also:

Object.toString()

hasWildcard

public boolean hasWildcard()

Returns true if the pattern contains any '*' or '?' or digit wildcard wildcard character.

setDigitWildcardChar

public void setDigitWildcardChar(char digitWildcard)

Sets the given character as a wildcard character in this pattern to match only digits ('0'-'9').

Parameters:

digitWildcard - The placeholder character for digits

copy

public StringPattern copy()

Returns a copy of this pattern. The values of the copy are independent of the origin. That means, changes to the copy will have no impact on this string pattern.

equals

public boolean equals(java.lang.Object obj)

Returns true if the given object is equal to the receiver.

Overrides:

equals in class java.lang.Object

See Also:

Object.equals(java.lang.Object)

hashCode

public int hashCode()

Returns a hash code value for the object.

Overrides:

hashCode in class java.lang.Object

See Also:

Object.hashCode()