## org.biojava.bio.symbol
Class AlphabetManager

    java.lang.Object
      org.biojava.bio.symbol.AlphabetManager

    public final class AlphabetManager

extends Object

Utility methods for working with Alphabets. Also acts as a registry for well-known alphabets.

The alphabet interfaces themselves don't give you a lot of help in actually getting an alphabet instance. This is where the AlphabetManager comes in handy. It helps out in serialization, generating derived alphabets and building CrossProductAlphabet instances. It also contains limited support for parsing complex alphabet names back into the alphabets.

Author:
  Matthew Pocock, Thomas Down, Mark Schreiber, George Waldon (alternate tokenization)

Constructor Summary
`AlphabetManager()`

Method Summary
`static Alphabet` `alphabetForName(String name)` Retrieve the alphabet for a specific name.
`static Iterator` `alphabets()` Get an iterator over all alphabets known.
`static Symbol` `createSymbol(Annotation annotation, List symList, Alphabet alpha)` Generates a new Symbol instance that represents the tuple of Symbols in symList.
`static Symbol` `createSymbol(Annotation annotation, Set symSet, Alphabet alpha)` Generates a new Symbol instance that represents the tuple of Symbols in symList.
`static Symbol` `createSymbol(char token, Annotation annotation, List symList, Alphabet alpha)` Deprecated. use the new version, without the token argument
`static Symbol` `createSymbol(char token, Annotation annotation, Set symSet, Alphabet alpha)` Deprecated. use the three-arg version of this method instead.
`static AtomicSymbol` `createSymbol(char token, String name, Annotation annotation)` Deprecated. Use the two-arg version of this method instead.
`static AtomicSymbol` `createSymbol(String name)` Generate a new AtomicSymbol instance with a name and an Empty Annotation.
`static AtomicSymbol` `createSymbol(String name, Annotation annotation)` Generate a new AtomicSymbol instance with a name and Annotation.
`static List` `factorize(Alphabet alpha, Set symSet)` Return a list of BasisSymbol instances that uniquely sum up all AtomicSymbol instances in symSet.
`static Alphabet` `generateCrossProductAlphaFromName(String name)` Generates a new CrossProductAlphabet from the give name.
`static Symbol` `getAllAmbiguitySymbol(FiniteAlphabet alpha)` Return the ambiguity symbol which matches all symbols in a given alphabet.
`static Set` `getAllSymbols(FiniteAlphabet alpha)` Return a set containing all possible symbols which can be considered members of a given alphabet, including ambiguous symbols.
`static AlphabetIndex` `getAlphabetIndex(FiniteAlphabet alpha)` Get an indexer for a specified alphabet.
`static AlphabetIndex` `getAlphabetIndex(Symbol[] syms)` Get an indexer for an array of symbols.
`static Alphabet` `getCrossProductAlphabet(List aList)` Retrieve a CrossProductAlphabet instance over the alphabets in aList.
`static Alphabet` `getCrossProductAlphabet(List aList, Alphabet parent)` Retrieve a CrossProductAlphabet instance over the alphabets in aList.
`static Alphabet` `getCrossProductAlphabet(List aList, String name)` Attempts to create a cross product alphabet and register it under a name.
`static Symbol` `getGapSymbol()` Get the special `gap' Symbol.
`static Symbol` `getGapSymbol(List alphas)` Get the gap symbol appropriate to this list of alphabets.
`static AlphabetManager` `instance()` Deprecated. all AlphabetManager methods have become static
`static void` `loadAlphabets(InputSource is)` Load additional Alphabets, defined in XML format, into the AlphabetManager's registry.
`static void` `registerAlphabet(String[] names, Alphabet alphabet)` Register and Alphabet by more than one name.
`static void` `registerAlphabet(String name, Alphabet alphabet)` Register an alphabet by name.
`static boolean` `registered(String name)` Has an Alphabet been registered by that name
`static Set` `registrations()` A set of names under which Alphabets have been registered.
`static Symbol` `symbolForLifeScienceID(LifeScienceIdentifier lsid)` Retreives the Symbol for the LSID
`static Symbol` `symbolForName(String name)` Deprecated. use symbolForLifeScienceID() instead

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

Constructor Detail

### AlphabetManager

    public AlphabetManager()

Method Detail

### instance

    public static AlphabetManager instance()

  Deprecated. all AlphabetManager methods have become static

  Retrieve the singleton instance.

  Returns:
    the AlphabetManager instance

### getAllAmbiguitySymbol

    public static Symbol getAllAmbiguitySymbol(FiniteAlphabet alpha)

  Return the ambiguity symbol which matches all symbols in a given alphabet.

  Parameters:
    `alpha` - The alphabet
  Returns:
    the ambiguity symbol
  Since:
    1.2

### getAllSymbols

    public static Set getAllSymbols(FiniteAlphabet alpha)

  Return a set containing all possible symbols which can be considered members of a given alphabet, including ambiguous symbols. Warning, this method can return large sets!

  Parameters:
    `alpha` - The alphabet
  Returns:
    The set of symbols that are members of `alpha`
  Since:
    1.2

### alphabetForName

    public static Alphabet alphabetForName(String name)
                                    throws NoSuchElementException

  Retrieve the alphabet for a specific name.

  Parameters:
    `name` - the name of the alphabet
  Returns:
    the alphabet object
  Throws:
    `NoSuchElementException` - if there is no alphabet by that name

### symbolForName

    public static Symbol symbolForName(String name)
                                throws NoSuchElementException

  Deprecated. use symbolForLifeScienceID() instead

  Retrieve the symbol represented a String object

  Parameters:
    `name` - of the string whose symbol you want to get
  Returns:
    The Symbol
  Throws:
    `NoSuchElementException` - if the string name is invalid.

### symbolForLifeScienceID

    public static Symbol symbolForLifeScienceID(LifeScienceIdentifier lsid)

  Retreives the Symbol for the LSID

  Parameters:
    `lsid` - the URN for the Symbol
  Returns:
    a reference to the Symbol

### registerAlphabet

    public static void registerAlphabet(String name,
                                        Alphabet alphabet)

  Register an alphabet by name.

  Parameters:
    `name` - the name by which it can be retrieved
    `alphabet` - the Alphabet to store

### registerAlphabet

    public static void registerAlphabet(String[] names,
                                        Alphabet alphabet)

  Register and Alphabet by more than one name. This allows aliasing of an alphabet with two or more names. It is equivalent to calling `registerAlphabet(String name, Alphabet alphabet)` several times.

  Parameters:
    `names` - the names by which it can be retrieved
    `alphabet` - the Alphabet to store
  Since:
    1.4

### registrations

    public static Set registrations()

  A set of names under which Alphabets have been registered.

  Returns:
    a `Set` of `Strings`

### registered

    public static boolean registered(String name)

  Has an Alphabet been registered by that name

  Parameters:
    `name` - the name of the alphabet
  Returns:
    true if it has or false otherwise

### alphabets

    public static Iterator alphabets()

  Get an iterator over all alphabets known.

  Returns:
    an Iterator over Alphabet objects

### getGapSymbol

    public static Symbol getGapSymbol()

  Get the special `gap' Symbol.

  The gap symbol is a Symbol that has an empty alphabet of matches. As such , ever alphabet contains gap, as there is no symbol that matches gap, so there is no case where an alphabet doesn't contain a symbol that matches gap.

  Gap can be thought of as an empty sub-space within the space of all possible symbols. If you are working in a cross-product alphabet, you should chose whether to use gap to represent 'no symbol', or a basis symbol of the appropriate size built entirely of gaps to represent 'no symbol in each of the slots'. Perhaps this could be explained better.

  Returns:
    the system-wide symbol that represents a gap

### getGapSymbol

    public static Symbol getGapSymbol(List alphas)

  Get the gap symbol appropriate to this list of alphabets.

  The gap symbol with have the same shape a the alphabet list. It will be as long as the list, and if any of the alphabets in the list have a dimension greater than 1, it will also insert the appropriate gap there.

  Parameters:
    `alphas` - List of alphabets
  Returns:
    the appropriate gap symbol for the alphabet list

### createSymbol

    public static AtomicSymbol createSymbol(String name,
                                            Annotation annotation)

  Generate a new AtomicSymbol instance with a name and Annotation.

  Use this method if you wish to create an AtomicSymbol instance. Initially it will not be a member of any alphabet.

  Parameters:
    `name` - the String returned by getName()
    `annotation` - the Annotation returned by getAnnotation()
  Returns:
    a new AtomicSymbol instance

### createSymbol

    public static AtomicSymbol createSymbol(String name)

  Generate a new AtomicSymbol instance with a name and an Empty Annotation.

  Use this method if you wish to create an AtomicSymbol instance. Initially it will not be a member of any alphabet.

  Parameters:
    `name` - the String returned by getName()
  Returns:
    a new AtomicSymbol instance

### createSymbol

    public static AtomicSymbol createSymbol(char token,
                                            String name,
                                            Annotation annotation)

  Deprecated. Use the two-arg version of this method instead.

  Generate a new AtomicSymbol instance with a token, name and Annotation.

  Use this method if you wish to create an AtomicSymbol instance. Initially it will not be a member of any alphabet.

  Parameters:
    `token` - the Char token returned by getToken() (ignpred as of BioJava 1.2)
    `name` - the String returned by getName()
    `annotation` - the Annotation returned by getAnnotation()
  Returns:
    a new AtomicSymbol instance

### createSymbol

    public static Symbol createSymbol(char token,
                                      Annotation annotation,
                                      List symList,
                                      Alphabet alpha)
                               throws IllegalSymbolException

  Deprecated. use the new version, without the token argument

  Generates a new Symbol instance that represents the tuple of Symbols in symList.

  This method is most useful for writing Alphabet implementations. It should not be invoked by casual users. Use alphabet.getSymbol(List) instead.

  Parameters:
    `annotation` - The annotation bundle for the symbol
    `token` - the Symbol's token [ignored since 1.2]
    `symList` - a list of Symbol objects
    `alpha` - the Alphabet that this Symbol will reside in
  Returns:
    a Symbol that encapsulates that List
  Throws:
    `IllegalSymbolException` - If the Symbol cannot be made

### createSymbol

    public static Symbol createSymbol(Annotation annotation,
                                      List symList,
                                      Alphabet alpha)
                               throws IllegalSymbolException

  Generates a new Symbol instance that represents the tuple of Symbols in symList. This will attempt to return the same symbol for the same list.

  This method is most useful for writing Alphabet implementations. It should not be invoked by casual users. Use alphabet.getSymbol(List) instead.

  Parameters:
    `annotation` - The annotation bundle for the Symbol
    `symList` - a list of Symbol objects
    `alpha` - the Alphabet that this Symbol will reside in
  Returns:
    a Symbol that encapsulates that List
  Throws:
    `IllegalSymbolException` - If the Symbol cannot be made

### createSymbol

    public static Symbol createSymbol(char token,
                                      Annotation annotation,
                                      Set symSet,
                                      Alphabet alpha)
                               throws IllegalSymbolException

  Deprecated. use the three-arg version of this method instead.

  Generates a new Symbol instance that represents the tuple of Symbols in symList.

  This method is most useful for writing Alphabet implementations. It should not be invoked by users. Use alphabet.getSymbol(Set) instead.

  Parameters:
    `token` - the Symbol's token [ignored since 1.2]
    `annotation` - the Symbol's Annotation
    `symSet` - a Set of Symbol objects
    `alpha` - the Alphabet that this Symbol will reside in
  Returns:
    a Symbol that encapsulates that List
  Throws:
    `IllegalSymbolException` - If the Symbol cannot be made

### createSymbol

    public static Symbol createSymbol(Annotation annotation,
                                      Set symSet,
                                      Alphabet alpha)
                               throws IllegalSymbolException

  Generates a new Symbol instance that represents the tuple of Symbols in symList.

  This method is most useful for writing Alphabet implementations. It should not be invoked by users. Use alphabet.getSymbol(Set) instead.

  Parameters:
    `annotation` - the Symbol's Annotation
    `symSet` - a Set of Symbol objects
    `alpha` - the Alphabet that this Symbol will reside in
  Returns:
    a Symbol that encapsulates that List
  Throws:
    `IllegalSymbolException` - If the Symbol cannot be made

### generateCrossProductAlphaFromName

    public static Alphabet generateCrossProductAlphaFromName(String name)

  Generates a new CrossProductAlphabet from the give name.

  Parameters:
    `name` - the name to parse
  Returns:
    the associated Alphabet

### getCrossProductAlphabet

    public static Alphabet getCrossProductAlphabet(List aList)

  Retrieve a CrossProductAlphabet instance over the alphabets in aList.

  If all of the alphabets in aList implements FiniteAlphabet then the method will return a FiniteAlphabet. Otherwise, it returns a non-finite alphabet.

  If you call this method twice with a list containing the same alphabets, it will return the same alphabet. This promotes the re-use of alphabets and helps to maintain the 'flyweight' principal for finite alphabet symbols.

  The resulting alphabet cpa will be retrievable via AlphabetManager.alphabetForName(cpa.getName())

  Parameters:
    `aList` - a list of Alphabet objects
  Returns:
    a CrossProductAlphabet that is over the alphabets in aList

### getCrossProductAlphabet

    public static Alphabet getCrossProductAlphabet(List aList,
                                                   String name)
                                            throws IllegalAlphabetException

  Attempts to create a cross product alphabet and register it under a name.

  Parameters:
    `aList` - A list of alphabets
    `name` - The name which the new alphabet will be registered under.
  Returns:
    The CrossProductAlphabet
  Throws:
    `IllegalAlphabetException` - If the Alphabet cannot be made or a different alphabet is already registed under this name.

### getCrossProductAlphabet

    public static Alphabet getCrossProductAlphabet(List aList,
                                                   Alphabet parent)

  Retrieve a CrossProductAlphabet instance over the alphabets in aList.

  This method is most usefull for implementors of cross-product alphabets, allowing them to safely build the matches alphabets for ambiguity symbols.

  If all of the alphabets in aList implements FiniteAlphabet then the method will return a FiniteAlphabet. Otherwise, it returns a non-finite alphabet.

  If you call this method twice with a list containing the same alphabets, it will return the same alphabet. This promotes the re-use of alphabets and helps to maintain the 'flyweight' principal for finite alphabet symbols.

  The resulting alphabet cpa will be retrievable via AlphabetManager.alphabetForName(cpa.getName())

  Parameters:
    `aList` - a list of Alphabet objects
    `parent` - a parent alphabet
  Returns:
    a CrossProductAlphabet that is over the alphabets in aList

### factorize

    public static List factorize(Alphabet alpha,
                                 Set symSet)
                          throws IllegalSymbolException

  Return a list of BasisSymbol instances that uniquely sum up all AtomicSymbol instances in symSet. If the symbol can't be represented by a single list of BasisSymbol instances, return null.

  This method is most useful for implementers of Alphabet and Symbol. It probably should not be invoked by users.

  Parameters:
    `symSet` - the Set of AtomicSymbol instances
    `alpha` - the Alphabet instance that the Symbols are from
  Returns:
    a List of BasisSymbols
  Throws:
    `IllegalSymbolException` - In practice it should not. If it does it probably indicates a subtle bug somewhere in AlphabetManager

### loadAlphabets

    public static void loadAlphabets(InputSource is)
                              throws SAXException,
                                     IOException,
                                     BioException

  Load additional Alphabets, defined in XML format, into the AlphabetManager's registry. These can the be retrieved by calling `alphabetForName`.

  Parameters:
    `is` - an `InputSource` encapsulating the document to be parsed
  Throws:
    `IOException` - if there is an error accessing the stream
    `SAXException` - if there is an error while parsing the document
    `BioException` - if a problem occurs when creating the new Alphabets.
  Since:
    1.3

### getAlphabetIndex

    public static AlphabetIndex getAlphabetIndex(FiniteAlphabet alpha)

  Get an indexer for a specified alphabet.

  Parameters:
    `alpha` - The alphabet to index
  Returns:
    an AlphabetIndex instance
  Since:
    1.1

### getAlphabetIndex

    public static AlphabetIndex getAlphabetIndex(Symbol[] syms)
                                          throws IllegalSymbolException,
                                                 BioException

  Get an indexer for an array of symbols.

  Parameters:
    `syms` - the Symbols to index in that order
  Returns:
    an AlphabetIndex instance
  Throws:
    `IllegalSymbolException`
    `BioException`
  Since:
    1.1