Rule (Apache Commons Codec 1.10 API)

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

Version:

$Id: Rule.html 928559 2014-11-10 02:53:54Z ggregory $

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`Rule.Phoneme`
`static interface`	`Rule.PhonemeExpr`
`static class`	`Rule.PhonemeList`
`static interface`	`Rule.RPattern` A minimal wrapper around the functionality of Pattern that we use, to allow for alternate implementations.

Field Summary

Fields
Modifier and Type Field and Description

static String ALL

static Rule.RPattern ALL_STRINGS_RMATCHER

Fields
Modifier and Type	Field and Description
`static String`	`ALL`
`static Rule.RPattern`	`ALL_STRINGS_RMATCHER`

Constructor Summary

Constructors
Constructor and Description

Rule(String pattern, String lContext, String rContext, Rule.PhonemeExpr phoneme)
Creates a new rule.

Constructors
Constructor and Description
`Rule(String pattern, String lContext, String rContext, Rule.PhonemeExpr phoneme)` Creates a new rule.

Method Summary

Methods
Modifier and Type	Method and Description
`static List<Rule>`	`getInstance(NameType nameType, RuleType rt, Languages.LanguageSet langs)` Gets rules for a combination of name type, rule type and languages.
`static List<Rule>`	`getInstance(NameType nameType, RuleType rt, String lang)` Gets rules for a combination of name type, rule type and a single language.
`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.
`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.
`Rule.RPattern`	`getLContext()` Gets the left context.
`String`	`getPattern()` Gets the pattern.
`Rule.PhonemeExpr`	`getPhoneme()` Gets the phoneme.
`Rule.RPattern`	`getRContext()` Gets the right context.
`boolean`	`patternAndContextMatches(CharSequence input, int i)` Decides if the pattern and context match the input starting at a position.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - ALL_STRINGS_RMATCHER
```
public static final Rule.RPattern ALL_STRINGS_RMATCHER
```
  - ALL
```
public static final String ALL
```
    See Also:
    Constant Field Values
- Constructor Detail
  - 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 Detail
  - 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

Class Rule

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

ALL_STRINGS_RMATCHER

ALL

Constructor Detail

Rule

Method Detail

getInstance

getInstance

getInstanceMap

getInstanceMap

getLContext

getPattern

getPhoneme

getRContext

patternAndContextMatches