nsIStreamListener
Last changed in Gecko 1.7 Suppose you had code that converted plain text into HTML. You could implement this interface to allow everyone else to use your conversion logic using a standard api.
Stream converter users
There are currently two ways to use a stream converter:
- Synchronous: Stream to Stream. You can supply the service with a stream of type X and it will convert it to your desired output type and return a converted (blocking) stream to you.
- Asynchronous:
nsIStreamListener
tonsIStreamListener
. You can supply data directly to the converter by calling it'snsIStreamListener.OnDataAvailable()
method. It will then convert that data from type X to your desired output type and return converted data to you via thensIStreamListener
you passed in by calling itsnsIStreamListener.OnDataAvailable()
method.
Stream converter suppliers
Registering a stream converter: Stream converter registration is a two step process. First of all the stream converter implementation must register itself with the component manager using a contractid in the format below. Second, the stream converter must add the contractid to the registry.
Stream converter contractid format (the stream converter root key is defined in this file):
@mozilla.org/streamconv;1?from=FROM_MIME_TYPE&to=TO_MIME_TYPE
Method overview
void asyncConvertData(in string aFromType, in string aToType, in nsIStreamListener aListener, in nsISupports aCtxt); |
nsIInputStream convert(in nsIInputStream aFromStream, in string aFromType, in string aToType, in nsISupports aCtxt); |
Methods
asyncConvertData()
Asynchronous version: Converts data arriving via the converter's nsIStreamListener.OnDataAvailable()
method from one type to another, pushing the converted data out to the caller via aListener::OnDataAvailable()
.
Use this method when you want to proxy (and convert) nsIStreamListener
callbacks asynchronously.
void asyncConvertData( in string aFromType, in string aToType, in nsIStreamListener aListener, in nsISupports aCtxt );
Parameters
-
aFromType
- The MIME type of the original/raw data.
-
aToType
- The MIME type of the converted data.
-
aListener
- The listener who receives the converted data.
-
aCtxt
- Either an opaque context, or a converter specific context (implementation specific).
convert()
Synchronous version: Converts a stream of one type, to a stream of another type.
Use this method when you have a stream you want to convert.
nsIInputStream convert( in nsIInputStream aFromStream, in string aFromType, in string aToType, in nsISupports aCtxt );
Parameters
-
aFromStream
- The stream representing the original/raw data.
-
aFromType
-
The MIME type of
aFromStream
. -
aToType
- The MIME type of the returned stream.
-
aCtxt
- Either an opaque context, or a converter specific context (implementation specific).
Return value
The converted stream.