dart-sdk/runtime/bin/output_stream.dart
sgjesse@google.com 4491ea144d Add writeString method to OutputStream
All output streams now supports writeString which takes the encoding
to be used when transforming the string into a sequence of bytes.

This change also introduces an Encoding interface and Encodings class
as a repository for the supported encodings. Currently this is only
UTF-8, ISO-8859-1 and ASCII. All methods in dart:io which previously
used a String to represent the encoding now uses objects implementing
Encoding.

In this change dart:io is still using the internal UTF-8 encoder used
by the HTTP implementation. I will look into using the one in dart:utf
in a separate change.

R=ager@google.com

BUG=
TEST=

Review URL: https://chromiumcodereview.appspot.com//9653026

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@5231 260f80e4-7a28-3924-810f-c04153c831b5
2012-03-09 13:49:20 +00:00

87 lines
3.2 KiB
Dart

// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
/**
* Output streams are used to write data sequentially to a data
* destination e.g. a connected socket or an open file.
*
* An output stream provides internal buffering of the data written
* through all calls to [write] and [writeFrom] if data cannot be
* written immediately to the communication channel. The callback set
* through [onNoPendingWrites] can be used to to keep the rate of
* writing in sync with the rate the system can actually write data to
* the underlying communication channel.
*/
interface OutputStream {
/**
* Writes the content of [buffer] to the stream. If [copyBuffer] is
* false ownership of the specified buffer is passed to the system
* and the caller should not change it afterwards. The default value
* for [copyBuffer] is true.
*
* Returns true if the data could be written to the underlying
* communication channel immediately. Otherwise the data is buffered
* by the output stream and will be sent as soon as possible.
*/
bool write(List<int> buffer, [bool copyBuffer]);
/**
* Writes [len] bytes from buffer [buffer] starting at offset
* [offset] to the output stream. If [offset] is not specified the
* default is 0. If [len] is not specified the default is the length
* of the buffer minus [offset] (i.e. writing from offset to the end
* of the buffer). The system will copy the data to be written so
* the caller can safely change [buffer] afterwards.
*
* Returns true if the data could be written to the underlying
* communication channel immediately. Otherwise the data is buffered
* by the output stream and will be sent as soon as possible.
*/
bool writeFrom(List<int> buffer, [int offset, int len]);
/**
* Write a string to the stream using the given [encoding].The
* default encoding is UTF-8 - [:Encoding.UTF_8:].
*
* Returns true if the data could be written to the underlying
* communication channel immediately. Otherwise the data is buffered
* by the output stream and will be sent as soon as possible.
*/
bool writeString(String string, [Encoding encoding]);
/**
* Indicate that all data has been written to the output
* stream. When all data has been written to the communication
* channel it will be closed.
*/
void close();
/**
* Close the communication channel immediately ignoring any buffered
* data.
*/
void destroy();
/**
* Sets the handler that gets called when the internal OS buffers
* have been flushed. This callback can be used to keep the rate of
* writing in sync with the rate the system can write data to the
* underlying communication channel.
*/
void set onNoPendingWrites(void callback());
/**
* Sets the handler that gets called when the underlying
* communication channel has been closed and no more data can be
* send.
*/
void set onClosed(void callback());
/**
* Sets the handler that gets called when the underlying
* communication channel gets into some kind of error situation.
*/
void set onError(void callback());
}