Package org.apache.commons.codec.language.bm

Class Rule

java.lang.Object
org.apache.commons.codec.language.bm.Rule
public class Rule extends Object
A phoneme rule.

Rules have a pattern, left context, right context, output phoneme, set of languages for which they apply and a logical flag indicating if all languages must be in play. A rule matches if:

  • the pattern matches at the current position
  • the string up until the beginning of the pattern matches the left context
  • the string from the end of the pattern matches the right context
  • logical is ALL and all languages are in scope; or
  • logical is any other value and at least one language is in scope

Rules are typically generated by parsing rules resources. In normal use, there will be no need for the user to explicitly construct their own.

Rules are immutable and thread-safe.

Rules resources

Rules are typically loaded from resource files. These are UTF-8 encoded text files. They are systematically named following the pattern:

org/apache/commons/codec/language/bm/${NameType#getName}_${RuleType#getName}_${language}.txt

The format of these resources is the following:

  • Rules: whitespace separated, double-quoted strings. There should be 4 columns to each row, and these will be interpreted as:
    1. pattern
    2. left context
    3. right context
    4. phoneme
  • End-of-line comments: Any occurrence of '//' will cause all text following on that line to be discarded as a comment.
  • Multi-line comments: Any line starting with '/*' will start multi-line commenting mode. This will skip all content until a line ending in '*' and '/' is found.
  • Blank lines: All blank lines will be skipped.
Since:
1.6

  • Field Details

  • Constructor Details

    • Rule

      public Rule(String pattern, String lContext, String rContext, Rule.PhonemeExpr phoneme)
      Creates a new rule.
      Parameters:
      pattern - the pattern
      lContext - the left context
      rContext - the right context
      phoneme - the resulting phoneme

  • Method Details

    • getInstance

      public static List<Rule> getInstance(NameType nameType, RuleType rt, Languages.LanguageSet langs)
      Gets rules for a combination of name type, rule type and languages.
      Parameters:
      nameType - the NameType to consider
      rt - the RuleType to consider
      langs - the set of languages to consider
      Returns:
      a list of Rules that apply

    • getInstance

      public static List<Rule> getInstance(NameType nameType, RuleType rt, String lang)
      Gets rules for a combination of name type, rule type and a single language.
      Parameters:
      nameType - the NameType to consider
      rt - the RuleType to consider
      lang - the language to consider
      Returns:
      a list of Rules that apply

    • getInstanceMap

      public static Map<String,List<Rule>> getInstanceMap(NameType nameType, RuleType rt, Languages.LanguageSet langs)
      Gets rules for a combination of name type, rule type and languages.
      Parameters:
      nameType - the NameType to consider
      rt - the RuleType to consider
      langs - the set of languages to consider
      Returns:
      a map containing all Rules that apply, grouped by the first character of the rule pattern
      Since:
      1.9

    • getInstanceMap

      public static Map<String,List<Rule>> getInstanceMap(NameType nameType, RuleType rt, String lang)
      Gets rules for a combination of name type, rule type and a single language.
      Parameters:
      nameType - the NameType to consider
      rt - the RuleType to consider
      lang - the language to consider
      Returns:
      a map containing all Rules that apply, grouped by the first character of the rule pattern
      Since:
      1.9

    • getLContext

      public Rule.RPattern getLContext()
      Gets the left context. This is a regular expression that must match to the left of the pattern.
      Returns:
      the left context Pattern

    • getPattern

      public String getPattern()
      Gets the pattern. This is a string-literal that must exactly match.
      Returns:
      the pattern

    • getPhoneme

      public Rule.PhonemeExpr getPhoneme()
      Gets the phoneme. If the rule matches, this is the phoneme associated with the pattern match.
      Returns:
      the phoneme

    • getRContext

      public Rule.RPattern getRContext()
      Gets the right context. This is a regular expression that must match to the right of the pattern.
      Returns:
      the right context Pattern

    • patternAndContextMatches

      public boolean patternAndContextMatches(CharSequence input, int i)
      Decides if the pattern and context match the input starting at a position. It is a match if the lContext matches input up to i, pattern matches at i and rContext matches from the end of the match of pattern to the end of input.
      Parameters:
      input - the input String
      i - the int position within the input
      Returns:
      true if the pattern and left/right context match, false otherwise