QNetworkProtocol(3qt)QNetworkProtocol(3qt)NAMEQNetworkProtocol - Common API for network protocols
SYNOPSIS
#include <qnetworkprotocol.h>
Inherits QObject.
Inherited by QFtp, QHttp, and QLocalFs.
Public Members
enum State { StWaiting = 0, StInProgress, StDone, StFailed, StStopped }
enum Operation { OpListChildren = 1, OpMkDir = 2, OpMkdir = OpMkDir,
OpRemove = 4, OpRename = 8, OpGet = 32, OpPut = 64 }
enum ConnectionState { ConHostFound, ConConnected, ConClosed }
enum Error { NoError = 0, ErrValid, ErrUnknownProtocol, ErrUnsupported,
ErrParse, ErrLoginIncorrect, ErrHostNotFound, ErrListChildren,
ErrListChlidren = ErrListChildren, ErrMkDir, ErrMkdir = ErrMkDir,
ErrRemove, ErrRename, ErrGet, ErrPut, ErrFileNotExisting,
ErrPermissionDenied }
QNetworkProtocol ()
virtual ~QNetworkProtocol ()
virtual void setUrl ( QUrlOperator * u )
virtual void setAutoDelete ( bool b, int i = 10000 )
bool autoDelete () const
virtual int supportedOperations () const
virtual void addOperation ( QNetworkOperation * op )
QUrlOperator * url () const
QNetworkOperation * operationInProgress () const
virtual void clearOperationQueue ()
virtual void stop ()
Signals
void data ( const QByteArray & data, QNetworkOperation * op )
void connectionStateChanged ( int state, const QString & data )
void finished ( QNetworkOperation * op )
void start ( QNetworkOperation * op )
void newChildren ( const QValueList<QUrlInfo> & i, QNetworkOperation *
op )
void newChild ( const QUrlInfo & i, QNetworkOperation * op )
void createdDirectory ( const QUrlInfo & i, QNetworkOperation * op )
void removed ( QNetworkOperation * op )
void itemChanged ( QNetworkOperation * op )
void dataTransferProgress ( int bytesDone, int bytesTotal,
QNetworkOperation * op )
Static Public Members
void registerNetworkProtocol ( const QString & protocol,
QNetworkProtocolFactoryBase * protocolFactory )
QNetworkProtocol * getNetworkProtocol ( const QString & protocol )
bool hasOnlyLocalFileSystem ()
Protected Members
virtual void operationListChildren ( QNetworkOperation * op )
virtual void operationMkDir ( QNetworkOperation * op )
virtual void operationRemove ( QNetworkOperation * op )
virtual void operationRename ( QNetworkOperation * op )
virtual void operationGet ( QNetworkOperation * op )
virtual void operationPut ( QNetworkOperation * op )
virtual bool checkConnection ( QNetworkOperation * op )
DESCRIPTION
The QNetworkProtocol class provides a common API for network protocols.
This is a base class which should be used for network protocols
implementations that can then be used in Qt (e.g. in the file dialog)
together with the QUrlOperator.
The easiest way to implement a new network protocol is to reimplement
the operation*() methods, e.g. operationGet(), etc. Only the supported
operations should be reimplemented. To specify which operations are
supported, also reimplement supportedOperations() and return an int
that is OR'd together using the supported operations from the
QNetworkProtocol::Operation enum.
When you implement a network protocol this way, it is important to emit
the correct signals. Also, always emit the finished() signal when an
operation is done (on success and on failure). Qt relies on correctly
emitted finished() signals.
For a detailed description of the Qt Network Architecture and how to
implement and use network protocols in Qt, see the Qt Network
Documentation.
See also Input/Output and Networking.
Member Type Documentation
QNetworkProtocol::ConnectionState
When the connection state of a network protocol changes it emits the
signal connectionStateChanged(). The first argument is one of the
following values:
QNetworkProtocol::ConHostFound - Host has been found.
QNetworkProtocol::ConConnected - Connection to the host has been
established.
QNetworkProtocol::ConClosed - Connection has been closed.
QNetworkProtocol::Error
When an operation fails (finishes unsuccessfully), the
QNetworkOperation of the operation returns an error code which has one
of the following values:
QNetworkProtocol::NoError - No error occurred.
QNetworkProtocol::ErrValid - The URL you are operating on is not valid.
QNetworkProtocol::ErrUnknownProtocol - There is no protocol
implementation available for the protocol of the URL you are operating
on (e.g. if the protocol is http and no http implementation has been
registered).
QNetworkProtocol::ErrUnsupported - The operation is not supported by
the protocol.
QNetworkProtocol::ErrParse - The URL could not be parsed correctly.
QNetworkProtocol::ErrLoginIncorrect - You needed to login but the
username or password is wrong.
QNetworkProtocol::ErrHostNotFound - The specified host (in the URL)
couldn't be found.
QNetworkProtocol::ErrListChildren - An error occurred while listing the
children (files).
QNetworkProtocol::ErrMkDir - An error occurred when creating a
directory.
QNetworkProtocol::ErrRemove - An error occurred when removing a child
(file).
QNetworkProtocol::ErrRename - An error occurred when renaming a child
(file).
QNetworkProtocol::ErrGet - An error occurred while getting (retrieving)
data.
QNetworkProtocol::ErrPut - An error occurred while putting (uploading)
data.
QNetworkProtocol::ErrFileNotExisting - A file which is needed by the
operation doesn't exist.
QNetworkProtocol::ErrPermissionDenied - Permission for doing the
operation has been denied.
You should also use these error codes when implementing custom network
protocols. If this is not possible, you can define your own error codes
by using integer values that don't conflict with any of these values.
QNetworkProtocol::Operation
This enum lists the possible operations that a network protocol can
support. supportedOperations() returns an int of these that is OR'd
together. Also, the type() of a QNetworkOperation is always one of
these values.
QNetworkProtocol::OpListChildren - List the children of a URL, e.g. of
a directory.
QNetworkProtocol::OpMkDir - Create a directory.
QNetworkProtocol::OpRemove - Remove a child (e.g. a file).
QNetworkProtocol::OpRename - Rename a child (e.g. a file).
QNetworkProtocol::OpGet - Get data from a location.
QNetworkProtocol::OpPut - Put data to a location.
QNetworkProtocol::State
This enum contains the state that a QNetworkOperation can have.
QNetworkProtocol::StWaiting - The operation is in the
QNetworkProtocol's queue waiting to be prcessed.
QNetworkProtocol::StInProgress - The operation is being processed.
QNetworkProtocol::StDone - The operation has been processed
succesfully.
QNetworkProtocol::StFailed - The operation has been processed but an
error occurred.
QNetworkProtocol::StStopped - The operation has been processed but has
been stopped before it finished, and is waiting to be processed.
MEMBER FUNCTION DOCUMENTATIONQNetworkProtocol::QNetworkProtocol ()
Constructor of the network protocol base class. Does some
initialization and connecting of signals and slots.
QNetworkProtocol::~QNetworkProtocol () [virtual]
Destructor.
void QNetworkProtocol::addOperation ( QNetworkOperation * op ) [virtual]
Adds the operation op to the operation queue. The operation will be
processed as soon as possible. This method returns immediately.
bool QNetworkProtocol::autoDelete () const
Returns TRUE if auto-deleting is enabled; otherwise returns FALSE.
See also QNetworkProtocol::setAutoDelete().
bool QNetworkProtocol::checkConnection ( QNetworkOperation * op ) [virtual
protected]
For processing operations the network protocol base class calls this
method quite often. This should be reimplemented by new network
protocols. It should return TRUE if the connection is OK (open);
otherwise it should return FALSE. If the connection is not open the
protocol should open it.
If the connection can't be opened (e.g. because you already tried but
the host couldn't be found), set the state of op to
QNetworkProtocol::StFailed and emit the finished() signal with this
QNetworkOperation as argument.
op is the operation that needs an open connection.
Example: network/networkprotocol/nntp.cpp.
void QNetworkProtocol::clearOperationQueue () [virtual]
Clears the operation queue.
void QNetworkProtocol::connectionStateChanged ( int state, const QString &
data ) [signal]
This signal is emitted whenever the state of the connection of the
network protocol is changed. state describes the new state, which is
one of, ConHostFound, ConConnected or ConClosed. data is a message
text.
void QNetworkProtocol::createdDirectory ( const QUrlInfo & i,
QNetworkOperation * op ) [signal]
This signal is emitted when mkdir() has been succesful and the
directory has been created. i holds the information about the new
directory. op is the pointer to the operation object which contains all
the information about the operation, including the state, etc. Using
op->arg( 0 ), you can get the file name of the new directory.
When a protocol emits this signal, QNetworkProtocol is smart enough to
let the QUrlOperator, which is used by the network protocol, emit its
corresponding signal.
void QNetworkProtocol::data ( const QByteArray & data, QNetworkOperation * op
) [signal]
This signal is emitted when new data has been received after calling
get() or put(). op holds the name of the file from which data is
retrieved or uploaded in its first argument, and the (raw) data in its
second argument. You can get them with op->arg( 0 ) and op->rawArg( 1
). op is the pointer to the operation object, which contains all the
information about the operation, including the state, etc.
When a protocol emits this signal, QNetworkProtocol is smart enough to
let the QUrlOperator (which is used by the network protocol) emit its
corresponding signal.
void QNetworkProtocol::dataTransferProgress ( int bytesDone, int bytesTotal,
QNetworkOperation * op ) [signal]
This signal is emitted during the transfer of data (using put() or
get()). bytesDone is how many bytes of bytesTotal have been
transferred. bytesTotal may be -1, which means that the total number of
bytes is not known. op is the pointer to the operation object which
contains all the information about the operation, including the state,
etc.
When a protocol emits this signal, QNetworkProtocol is smart enough to
let the QUrlOperator, which is used by the network protocol, emit its
corresponding signal.
void QNetworkProtocol::finished ( QNetworkOperation * op ) [signal]
This signal is emitted when an operation finishes. This signal is
always emitted, for both success and failure. op is the pointer to the
operation object which contains all the information about the
operation, including the state, etc. Check the state and error code of
the operation object to determine whether or not the operation was
successful.
When a protocol emits this signal, QNetworkProtocol is smart enough to
let the QUrlOperator, which is used by the network protocol, emit its
corresponding signal.
QNetworkProtocol * QNetworkProtocol::getNetworkProtocol ( const QString &
protocol ) [static]
Static method to get a new instance of the network protocol protocol.
For example, if you need to do some FTP operations, do the following:
QFtp *ftp = QNetworkProtocol::getNetworkProtocol( "ftp" );
This returns a pointer to a new instance of an ftp implementation or
null if no protocol for ftp was registered. The ownership of the
pointer is transferred to you, so you must delete it if you don't need
it anymore.
Normally you should not work directly with network protocols, so you
will not need to call this method yourself. Instead, use QUrlOperator,
which makes working with network protocols much more convenient.
See also QUrlOperator.
bool QNetworkProtocol::hasOnlyLocalFileSystem () [static]
Returns TRUE if the only protocol registered is for working on the
local filesystem; returns FALSE if other network protocols are also
registered.
void QNetworkProtocol::itemChanged ( QNetworkOperation * op ) [signal]
This signal is emitted whenever a file which is a child of this URL has
been changed, e.g. by successfully calling rename(). op holds the
original and the new file names in the first and second arguments,
accessible with op->arg( 0 ) and op->arg( 1 ) respectively. op is the
pointer to the operation object which contains all the information
about the operation, including the state, etc.
When a protocol emits this signal, QNetworkProtocol is smart enough to
let the QUrlOperator, which is used by the network protocol, emit its
corresponding signal.
void QNetworkProtocol::newChild ( const QUrlInfo & i, QNetworkOperation * op )
[signal]
This signal is emitted if a new child (file) has been read.
QNetworkProtocol automatically connects it to a slot which creates a
list of QUrlInfo objects (with just one QUrlInfo i) and emits the
newChildren() signal with this list. op is the pointer to the operation
object which contains all the information about the operation that has
finished, including the state, etc.
This is just a convenience signal useful for implementing your own
network protocol. In all other cases connect to the newChildren()
signal with its list of QUrlInfo objects.
void QNetworkProtocol::newChildren ( const QValueList<QUrlInfo> & i,
QNetworkOperation * op ) [signal]
This signal is emitted after listChildren() was called and new children
(files) have been read from the list of files. i holds the information
about the new children. op is the pointer to the operation object which
contains all the information about the operation, including the state,
etc.
When a protocol emits this signal, QNetworkProtocol is smart enough to
let the QUrlOperator, which is used by the network protocol, emit its
corresponding signal.
When implementing your own network protocol and reading children, you
usually don't read one child at once, but rather a list of them. That's
why this signal takes a list of QUrlInfo objects. If you prefer to read
just one child at a time you can use the convenience signal newChild(),
which takes a single QUrlInfo object.
void QNetworkProtocol::operationGet ( QNetworkOperation * op ) [virtual
protected]
When implementing a new network protocol, this method should be
reimplemented if the protocol supports getting data; this method should
then process the QNetworkOperation.
When you reimplement this method it's very important that you emit the
correct signals at the correct time (especially the finished() signal
after processing an operation). Take a look at the Qt Network
Documentation which describes in detail how to reimplement this method.
You may also want to look at the example implementation in
examples/network/networkprotocol/nntp.cpp.
op is the pointer to the operation object which contains all the
information on the operation that has finished, including the state,
etc.
Example: network/networkprotocol/nntp.cpp.
QNetworkOperation * QNetworkProtocol::operationInProgress () const
Returns the operation, which is being processed, or 0 of no operation
is being processed at the moment.
void QNetworkProtocol::operationListChildren ( QNetworkOperation * op )
[virtual protected]
When implementing a new network protocol, this method should be
reimplemented if the protocol supports listing children (files); this
method should then process this QNetworkOperation.
When you reimplement this method it's very important that you emit the
correct signals at the correct time (especially the finished() signal
after processing an operation). Take a look at the Qt Network
Documentation which describes in detail how to reimplement this method.
You may also want to look at the example implementation in
examples/network/networkprotocol/nntp.cpp.
op is the pointer to the operation object which contains all the
information on the operation that has finished, including the state,
etc.
Example: network/networkprotocol/nntp.cpp.
void QNetworkProtocol::operationMkDir ( QNetworkOperation * op ) [virtual
protected]
When implementing a new network protocol, this method should be
reimplemented if the protocol supports making directories; this method
should then process this QNetworkOperation.
When you reimplement this method it's very important that you emit the
correct signals at the correct time (especially the finished() signal
after processing an operation). Take a look at the Qt Network
Documentation which describes in detail how to reimplement this method.
You may also want to look at the example implementation in
examples/network/networkprotocol/nntp.cpp.
op is the pointer to the operation object which contains all the
information on the operation that has finished, including the state,
etc.
void QNetworkProtocol::operationPut ( QNetworkOperation * op ) [virtual
protected]
When implementing a new network protocol, this method should be
reimplemented if the protocol supports putting (uploading) data; this
method should then process the QNetworkOperation.
When you reimplement this method it's very important that you emit the
correct signals at the correct time (especially the finished() signal
after processing an operation). Take a look at the Qt Network
Documentation which describes in detail how to reimplement this method.
You may also want to look at the example implementation in
examples/network/networkprotocol/nntp.cpp.
op is the pointer to the operation object which contains all the
information on the operation that has finished, including the state,
etc.
void QNetworkProtocol::operationRemove ( QNetworkOperation * op ) [virtual
protected]
When implementing a new network protocol, this method should be
reimplemented if the protocol supports removing children (files); this
method should then process this QNetworkOperation.
When you reimplement this method it's very important that you emit the
correct signals at the correct time (especially the finished() signal
after processing an operation). Take a look at the Qt Network
Documentation which is describes in detail how to reimplement this
method. You may also want to look at the example implementation in
examples/network/networkprotocol/nntp.cpp.
op is the pointer to the operation object which contains all the
information on the operation that has finished, including the state,
etc.
void QNetworkProtocol::operationRename ( QNetworkOperation * op ) [virtual
protected]
When implementing a new newtork protocol, this method should be
reimplemented if the protocol supports renaming children (files); this
method should then process this QNetworkOperation.
When you reimplement this method it's very important that you emit the
correct signals at the correct time (especially the finished() signal
after processing an operation). Take a look at the Qt Network
Documentation which describes in detail how to reimplement this method.
You may also want to look at the example implementation in
examples/network/networkprotocol/nntp.cpp.
op is the pointer to the operation object which contains all the
information on the operation that has finished, including the state,
etc.
void QNetworkProtocol::registerNetworkProtocol ( const QString & protocol,
QNetworkProtocolFactoryBase * protocolFactory ) [static]
Static method to register a network protocol for Qt. For example, if
you have an implementation of NNTP (called Nntp) which is derived from
QNetworkProtocol, call:
QNetworkProtocol::registerNetworkProtocol( "nntp", new QNetworkProtocolFactory<Nntp> );
after which your implementation is registered for future nntp
operations.
The name of the protocol is given in protocol and a pointer to the
protocol factory is given in protocolFactory.
void QNetworkProtocol::removed ( QNetworkOperation * op ) [signal]
This signal is emitted when remove() has been succesful and the file
has been removed. op holds the file name of the removed file in the
first argument, accessible with op->arg( 0 ). op is the pointer to the
operation object which contains all the information about the
operation, including the state, etc.
When a protocol emits this signal, QNetworkProtocol is smart enough to
let the QUrlOperator, which is used by the network protocol, emit its
corresponding signal.
void QNetworkProtocol::setAutoDelete ( bool b, int i = 10000 ) [virtual]
Because it's sometimes hard to take care of removing network protocol
instances, QNetworkProtocol provides an auto-delete mechanism. If you
set b to TRUE, the network protocol instance is removed after it has
been inactive for i milliseconds (i.e. i milliseconds after the last
operation has been processed). If you set b to FALSE the auto-delete
mechanism is switched off.
If you switch on auto-delete, the QNetworkProtocol also deletes its
QUrlOperator.
void QNetworkProtocol::setUrl ( QUrlOperator * u ) [virtual]
Sets the QUrlOperator, on which the protocol works, to u.
See also QUrlOperator.
void QNetworkProtocol::start ( QNetworkOperation * op ) [signal]
Some operations (such as listChildren()) emit this signal when they
start processing the operation. op is the pointer to the operation
object which contains all the information about the operation,
including the state, etc.
When a protocol emits this signal, QNetworkProtocol is smart enough to
let the QUrlOperator, which is used by the network protocol, emit its
corresponding signal.
void QNetworkProtocol::stop () [virtual]
Stops the current operation that is being processed and clears all
waiting operations.
int QNetworkProtocol::supportedOperations () const [virtual]
Returns an int that is OR'd together using the enum values of
QNetworkProtocol::Operation, which describes which operations are
supported by the network protocol. Should be reimplemented by new
network protocols.
Example: network/networkprotocol/nntp.cpp.
QUrlOperator * QNetworkProtocol::url () const
Returns the QUrlOperator on which the protocol works.
SEE ALSO
http://doc.trolltech.com/qnetworkprotocol.html
http://www.trolltech.com/faq/tech.html
COPYRIGHT
Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com. See the
license file included in the distribution for a complete license
statement.
AUTHOR
Generated automatically from the source code.
BUGS
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Trolltech AS 2 February 2007 QNetworkProtocol(3qt)