CharacterEncoderImplementations__ISO10646_to_JavaText.st
author Jan Vrany <jan.vrany@fit.cvut.cz>
Wed, 03 Jun 2015 21:55:34 +0100
branchjv
changeset 18470 9e4db770f8f5
parent 18120 e3a375d5f6a8
child 23107 40173e082cbc
permissions -rw-r--r--
Optimize for fast-path in String >> at: Avoid jumps in String >> at: for common case the receiver is an instance of String and thus has no instance variables. Similar as fix 877a8f1b326d for Arrays.

"
 COPYRIGHT (c) 2006 by eXept Software AG
              All Rights Reserved

 This software is furnished under a license and may be used
 only in accordance with the terms of that license and with the
 inclusion of the above copyright notice.   This software may not
 be provided or otherwise made available to, or used by, any
 other person.  No title to or ownership of the software is
 hereby transferred.
"
"{ Package: 'stx:libbasic' }"

"{ NameSpace: CharacterEncoderImplementations }"

TwoByteEncoder subclass:#ISO10646_to_JavaText
	instanceVariableNames:''
	classVariableNames:''
	poolDictionaries:''
	category:'Collections-Text-Encodings'
!

!ISO10646_to_JavaText class methodsFor:'documentation'!

copyright
"
 COPYRIGHT (c) 2006 by eXept Software AG
              All Rights Reserved

 This software is furnished under a license and may be used
 only in accordance with the terms of that license and with the
 inclusion of the above copyright notice.   This software may not
 be provided or otherwise made available to, or used by, any
 other person.  No title to or ownership of the software is
 hereby transferred.
"
!

documentation
"
    Translates \uXXXX-escapes in the text
"
! !

!ISO10646_to_JavaText methodsFor:'encoding & decoding'!

decode:aCode
    self shouldNotImplement "/ no single byte conversion possible
!

decodeString:aStringOrByteCollection
    "given a string in JavaText encoding (i.e. with \uXXXX escaped characters),
     return a new string containing the same characters, in 16bit (or more) encoding.
     Returns either a normal String, a TwoByteString or a FourByteString instance.
     Only useful, when reading Java property and resource files.
     This only handles up-to 30bit characters."

    |nBits ch 
     in out codePoint t|

    nBits := 8.
    in := aStringOrByteCollection readStream.
    out := WriteStream on:(String new:10).
    [in atEnd] whileFalse:[
        ch := in next.
        ch == $\ ifTrue:[
            in peekOrNil == $u ifTrue:[
                in next.
                codePoint := 0.
                4 timesRepeat:[
                    ch := in peekOrNil.
                    codePoint := (codePoint * 16) + ch digitValue.
                    in next.
                ].
                codePoint > 16rFF ifTrue:[
                    codePoint > 16rFFFF ifTrue:[
                        nBits < 32 ifTrue:[
                            t := out contents.
                            out := WriteStream on:(Unicode32String fromString:t).
                            out position:t size.
                            nBits := 32.
                        ]
                    ] ifFalse:[
                        nBits < 16 ifTrue:[
                            t := out contents.
                            out := WriteStream on:(Unicode16String fromString:t).
                            out position:t size.
                            nBits := 16.
                        ]
                    ]
                ].
                out nextPut:(Character value:codePoint).
            ] ifFalse:[
                out nextPut:ch
            ]
        ] ifFalse:[
            out nextPut:ch
        ].
    ].
    ^ out contents

    "
     CharacterEncoderImplementations::ISO10646_to_JavaText
        decodeString:'AB\u1234CD' 
    "

    "Modified: / 23-10-2006 / 13:23:18 / cg"
!

encode:aCode
    self shouldNotImplement "/ no single byte conversion possible
!

encodeString:aUnicodeString
    "return the JavaText representation of aUnicodeString.
     The resulting string is only useful to be stored on some external file,
     not for being used inside ST/X."

    |ch in out codePoint|

    in := aUnicodeString readStream.
    out := WriteStream on:(String new:10).
    [in atEnd] whileFalse:[
        ch := in next.
        codePoint := ch codePoint.
        (codePoint between:16r20 and:16r7F) ifTrue:[
            out nextPut:ch.
        ] ifFalse:[
            out nextPutAll:'\u'.
            out nextPutAll:((codePoint printStringRadix:16) leftPaddedTo:4 with:$0).
        ].
    ].
    ^ out contents

    "
     CharacterEncoderImplementations::ISO10646_to_JavaText
        encodeString:'hello '  

     CharacterEncoderImplementations::ISO10646_to_JavaText
        decodeString:(CharacterEncoderImplementations::ISO10646_to_JavaText encodeString:'hello ') 
    "

    "Modified: / 23-10-2006 / 13:25:03 / cg"
! !

!ISO10646_to_JavaText class methodsFor:'documentation'!

version
    ^ '$Header: /cvs/stx/stx/libbasic/CharacterEncoderImplementations__ISO10646_to_JavaText.st,v 1.1 2014-02-05 17:11:06 cg Exp $'
!

version_CVS
    ^ '$Header: /cvs/stx/stx/libbasic/CharacterEncoderImplementations__ISO10646_to_JavaText.st,v 1.1 2014-02-05 17:11:06 cg Exp $'
! !