Class: SplittingWriteStream

• Inheritance
• Description
• Related information
• Class protocol
  • instance creation
• Instance protocol
  • accessing
  • private access
  • redirect messages
  • writing
• Examples

Inheritance:

   Object
   |
   +--Stream
      |
      +--SplittingWriteStream

Package:

stx:libbasic2

Category:

Streams-Misc

Version:

rev: 1.8 date: 2017/09/21 10:44:18

user: cg

file: SplittingWriteStream.st directory: libbasic2

module: stx stc-classLibrary: libbasic2

Author:

Claus Gittinger (cg@exept)

Description:

A stream duplicator - everything written onto a splittingWriteStream
is written to two real streams.
Useful, if you have to send something to two files/destinations
simultaneously, and do not want to (or cannot) buffer it.
Especially useful, to generate a checksum, 
while sending something to a file 
(if one of the output streams is a checksummer).



[instance variables:]
    outStream1      <Stream>       actual output streams
    outStream2      <Stream>

[class variables:]

Related information:

    WriteStream

Class protocol:

 on: stream1 and: stream2

Instance protocol:

 outStream1

return the value of the instance variable 'outStream1' (automatically generated)

 outStream1: something

set the value of the instance variable 'outStream1' (automatically generated)

 outStream2

return the value of the instance variable 'outStream2' (automatically generated)

 outStream2: something

set the value of the instance variable 'outStream2' (automatically generated)

 setOutStream1: stream1 outStream2: stream2

 doesNotUnderstand: aMessage

if my superclass implements the message, it can be forwarded to both streams.

 clear

 close

 contents

 endEntry

 flush

 nextPut: something

 nextPutAll: something

 nextPutAll: aCollection startingAt: start to: stop

 nextPutAllUnicode: aString

(comment from inherited method)
normal streams can not handle multi-byte characters, so convert them to utf8

Examples:

  |s1 s2 splitter|

  s1 := '/tmp/foo1' asFilename writeStream.
  s2 := '/tmp/foo2' asFilename writeStream.
  splitter := SplittingWriteStream on:s1 and:s2.
  splitter nextPutAll:'hello world'.
  splitter close.

  |s1 s2 splitter hash|

  s1 := '/tmp/foo1' asFilename writeStream.
  s2 := SHA1Stream new.
  splitter := SplittingWriteStream on:s1 and:s2.
  splitter nextPutAll:'hello world'.
  splitter close.
  hash := s2 hashValue. 
  self assert:(hash = (SHA1Stream hashValueOf:'hello world'))