"

 COPYRIGHT (c) 1995 by Claus Gittinger

              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.

 This is a demo example:

 THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTOR ``AS IS'' AND

 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 ARE DISCLAIMED.  IN NO EVENT SHALL THE CONTRIBUTOR BE LIABLE

 FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 SUCH DAMAGE.

"

"{ Package: 'stx:libbasic2' }"

ArrayedCollection variableByteSubclass:#BooleanArray

	instanceVariableNames:'tally'

	classVariableNames:''

	poolDictionaries:''

	category:'Collections-Arrayed'

!

!BooleanArray class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1995 by Claus Gittinger

              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.

 This is a demo example:

 THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTOR ``AS IS'' AND

 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 ARE DISCLAIMED.  IN NO EVENT SHALL THE CONTRIBUTOR BE LIABLE

 FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 SUCH DAMAGE.

"

!

documentation

"

    This is a simple demo class only; currently not used in the system.

    example for bulk boolean data (requires only 1/32th the memory

    compared to an array of booleans).

    This one stores 8 booleans per byte. Since instances store bits in multiples

    of 8, we have to keep the real size of the collection in an extra instance

    variable (tally).

    It may be useful if huge boolean arrays are to be used.

    Bits 1 to 8 of the BooleanArray are stored in bits 8 to 1 of the

    corresponding byte, to allow easy mapping to ASN.1 BIT STRING encoding

    in the BER.

    [memory requirements:]

        OBJ-HEADER + ((size + 7) // 8)

    [see also:]

        ByteArray WordArray Array

    [author:]

        Claus Gittinger

"

!

examples

"

                                                                        [exBegin]

    (BooleanArray new:7) inspect

                                                                        [exEnd]

                                                                        [exBegin]

    (BooleanArray new:7) basicInspect

                                                                        [exEnd]

                                                                        [exBegin]

    |flags|

    flags := BooleanArray new:1000000.

    (flags at:9999) printNL.

    flags at:9999 put:true.

    (flags at:9999) printNL.

                                                                        [exEnd]

"

! !

!BooleanArray class methodsFor:'instance creation'!

new:size

    "return a new instance, capable of holding size booleans"

    |nBytes|

    nBytes := size // 8.

    (size \\ 8) ~~ 0 ifTrue:[nBytes := nBytes + 1].

    ^ (super new:nBytes) setTally:size

    "

     BooleanArray new:10

    "

! !

!BooleanArray methodsFor:'accessing'!

at:index

    "retrieve the boolean at index"

    |byte mask i0|

    (index between:1 and:tally) ifFalse:[

        ^ self subscriptBoundsError:index

    ].

    i0 := index - 1.

    byte := super basicAt:(i0 // 8)+1.

    mask := 1 bitShift:(7 - (i0 \\ 8)).

    ^ (byte bitAnd:mask) ~~ 0

    "

     (BooleanArray new:1000) at:555

    "

    "

     |b|

     b := BooleanArray new:1000.

     b at:555 put:true.

     b at:555   

    "

    "Modified: / 31.7.1997 / 18:37:25 / cg"

    "Modified: / 23.5.1999 / 20:02:57 / stefan"

!

at:index put:aBoolean

    "store the argument, aBoolean at index; return aBoolean."

    |byte mask idx i0|

    (index between:1 and:tally) ifFalse:[

        ^ self subscriptBoundsError:index

    ].

    i0 := index - 1.

    idx := (i0 // 8) + 1.

    byte := super basicAt:idx.

    mask := 1 bitShift:(7 - (i0 \\ 8)).

    aBoolean == true ifTrue:[

        byte := byte bitOr:mask

    ] ifFalse:[

        aBoolean == false ifTrue:[

            byte := byte bitAnd:(mask bitInvert)

        ] ifFalse:[

            "/ not true or false

            ^ self elementBoundsError:aBoolean

        ]

    ].

    super basicAt:idx put:byte.

    ^ aBoolean.

    "

     |b|

     b := BooleanArray new:1000.

     b at:555 put:true.

     b at:555   

    "

    "Modified: / 31.7.1997 / 18:37:35 / cg"

    "Modified: / 23.5.1999 / 20:02:42 / stefan"

! !

!BooleanArray methodsFor:'filling & replacing'!

atAllPut:aBoolean

    |v|

    aBoolean == true ifTrue:[

        v := 255

    ] ifFalse:[

        aBoolean == false ifTrue:[

            v := 0

        ] ifFalse:[

            "/

            "/ booleanArrays can only hold true and false

            "/

            ^ self elementBoundsError:aBoolean

        ]

    ].

    1 to:self basicSize do:[:i |

        super basicAt:i put:v

    ].

! !

!BooleanArray methodsFor:'private'!

setTally:size

    tally := size

! !

!BooleanArray methodsFor:'queries'!

defaultElement

    ^ false

!

size

    "return the size of the receiver"

    ^ tally

! !

!BooleanArray class methodsFor:'documentation'!

version

    ^ '$Header: /cvs/stx/stx/libbasic2/BooleanArray.st,v 1.11 2003-04-22 09:38:23 cg Exp $'

! !