"{ Package: 'stx:goodies/xtreams/support' }"

"{ NameSpace: Xtreams }"

Object subclass:#Encoder

	instanceVariableNames:''

	classVariableNames:'DialectEncoder Encoders'

	poolDictionaries:''

	category:'Xtreams-Support'

!

Encoder comment:'Abstract character encoder class defines the API and maintains a registry of known encoders (Encoders). Also provides a hook to allow plugging in dialect specific encoders (DialectEncoder) as a secondary encoder resource.

Shared Variables

	DialectEncoder	<Class> optional dialect specific encoder class providing support for additional encodings

	Encoders	<Dictionary key: Symbol value: Class> maps encoding names to encoders

'

!

!Encoder class methodsFor:'instance creation'!

for: anEncoding

        anEncoding isSymbol ifFalse: [ ^anEncoding streamingAsEncoder ].

        ^Encoders at: anEncoding ifAbsent: [

                DialectEncoder

                        ifNil: [ self error: 'Unknown encoding!!' ]

                        ifNotNil: [ DialectEncoder for: anEncoding ] ]

!

streamingAsEncoder

	^self new

! !

!Encoder class methodsFor:'accessing'!

encoders

	^Encoders ifNil: [ Encoders := IdentityDictionary new ]

! !

!Encoder methodsFor:'accessing'!

backupState

!

decodeFrom: aReadStream

	^self subclassResponsibility

!

encode: aCharacter on: aWriteStream

	^self subclassResponsibility

!

restoreState

!

streamingAsEncoder

	^self

! !

!Encoder class methodsFor:'documentation'!

version_SVN

    ^ '$Id$'

! !