Class CharSet
- All Implemented Interfaces:
- Serializable
Instances are immutable, but instances of subclasses may not be.
#ThreadSafe#
- Since:
- 1.0
- See Also:
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Field SummaryFieldsModifier and TypeFieldDescriptionstatic final CharSetA CharSet defining ASCII alphabetic characters "a-zA-Z".static final CharSetA CharSet defining ASCII alphabetic characters "a-z".static final CharSetA CharSet defining ASCII alphabetic characters "A-Z".static final CharSetA CharSet defining ASCII alphabetic characters "0-9".A Map of the common cases used in the factory.static final CharSetA CharSet defining no characters.
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Constructor SummaryConstructors
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Method SummaryModifier and TypeMethodDescriptionprotected voidAdd a set definition string to theCharSet.booleancontains(char ch) Does theCharSetcontain the specified characterch.booleanCompares twoCharSetobjects, returning true if they represent exactly the same set of characters defined in the same way.static CharSetgetInstance(String... setStrs) Factory method to create a new CharSet using a special syntax.inthashCode()Gets a hash code compatible with the equals method.toString()Gets a string representation of the set.
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Field Details- 
EMPTYA CharSet defining no characters.- Since:
- 2.0
 
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ASCII_ALPHAA CharSet defining ASCII alphabetic characters "a-zA-Z".- Since:
- 2.0
 
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ASCII_ALPHA_LOWERA CharSet defining ASCII alphabetic characters "a-z".- Since:
- 2.0
 
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ASCII_ALPHA_UPPERA CharSet defining ASCII alphabetic characters "A-Z".- Since:
- 2.0
 
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ASCII_NUMERICA CharSet defining ASCII alphabetic characters "0-9".- Since:
- 2.0
 
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COMMONA Map of the common cases used in the factory. Subclasses can add more common patterns if desired- Since:
- 2.0
 
 
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Constructor Details- 
CharSetConstructs a new CharSet using the set syntax. Each string is merged in with the set.- Parameters:
- set- Strings to merge into the initial set
- Throws:
- NullPointerException- if set is- null
 
 
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Method Details- 
getInstanceFactory method to create a new CharSet using a special syntax.- nullor empty string ("") - set containing no characters
- Single character, such as "a" - set containing just that character
- Multi character, such as "a-e" - set containing characters from one character to the other
- Negated, such as "^a" or "^a-e" - set containing all characters except those defined
- Combinations, such as "abe-g" - set containing all the characters from the individual sets
 The matching order is: - Negated multi character range, such as "^a-e"
- Ordinary multi character range, such as "a-e"
- Negated single character, such as "^a"
- Ordinary single character, such as "a"
 Matching works left to right. Once a match is found the search starts again from the next character. If the same range is defined twice using the same syntax, only one range will be kept. Thus, "a-ca-c" creates only one range of "a-c". If the start and end of a range are in the wrong order, they are reversed. Thus "a-e" is the same as "e-a". As a result, "a-ee-a" would create only one range, as the "a-e" and "e-a" are the same. The set of characters represented is the union of the specified ranges. There are two ways to add a literal negation character ( ^):- As the last character in a string, e.g. CharSet.getInstance("a-z^")
- As a separate element, e.g. CharSet.getInstance("^", "a-z")
 Examples using the negation character: CharSet.getInstance("^a-c").contains('a') = false CharSet.getInstance("^a-c").contains('d') = true CharSet.getInstance("^^a-c").contains('a') = true // (only '^' is negated) CharSet.getInstance("^^a-c").contains('^') = false CharSet.getInstance("^a-cd-f").contains('d') = true CharSet.getInstance("a-c^").contains('^') = true CharSet.getInstance("^", "a-c").contains('^') = trueAll CharSet objects returned by this method will be immutable. - Parameters:
- setStrs- Strings to merge into the set, may be null
- Returns:
- a CharSet instance
- Since:
- 2.4
 
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addAdd a set definition string to theCharSet.- Parameters:
- str- set definition string
 
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containsDoes theCharSetcontain the specified characterch.- Parameters:
- ch- the character to check for
- Returns:
- trueif the set contains the characters
 
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equalsCompares twoCharSetobjects, returning true if they represent exactly the same set of characters defined in the same way.The two sets abcanda-care not equal according to this method.
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hashCodeGets a hash code compatible with the equals method.
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toStringGets a string representation of the set.
 
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