com.trolltech.qt.network
Class QTcpServer

java.lang.Object
  extended by com.trolltech.qt.internal.QSignalEmitterInternal
      extended by com.trolltech.qt.QSignalEmitter
          extended by com.trolltech.qt.QtJambiObject
              extended by com.trolltech.qt.core.QObject
                  extended by com.trolltech.qt.network.QTcpServer
All Implemented Interfaces:
QtJambiInterface

public class QTcpServer
extends QObject

The QTcpServer class provides a TCP-based server. This class makes it possible to accept incoming TCP connections. You can specify the port or have QTcpServer pick one automatically. You can listen on a specific address or on all the machine's addresses.

Call listen() to have the server listen for incoming connections. The newConnection() signal is then emitted each time a client connects to the server.

Call nextPendingConnection() to accept the pending connection as a connected QTcpSocket. The function returns a pointer to a QTcpSocket in QAbstractSocket::ConnectedState that you can use for communicating with the client.

If an error occurs, serverError() returns the type of error, and errorString() can be called to get a human readable description of what happened.

When listening for connections, the address and port on which the server is listening are available as serverAddress() and serverPort().

Calling close() makes QTcpServer stop listening for incoming connections.

Although QTcpServer is mostly designed for use with an event loop, it's possible to use it without one. In that case, you must use waitForNewConnection(), which blocks until either a connection is available or a timeout expires.

See also:
QTcpSocket, Fortune Server Example, Threaded Fortune Server Example, Loopback Example, and Torrent Example.


Nested Class Summary
static class QTcpServer.Result
           
 
Nested classes/interfaces inherited from class com.trolltech.qt.QSignalEmitter
QSignalEmitter.AbstractSignal, QSignalEmitter.PrivateSignal0, QSignalEmitter.PrivateSignal1, QSignalEmitter.PrivateSignal2, QSignalEmitter.PrivateSignal3, QSignalEmitter.PrivateSignal4, QSignalEmitter.PrivateSignal5, QSignalEmitter.PrivateSignal6, QSignalEmitter.PrivateSignal7, QSignalEmitter.PrivateSignal8, QSignalEmitter.PrivateSignal9, QSignalEmitter.Signal0, QSignalEmitter.Signal1, QSignalEmitter.Signal2, QSignalEmitter.Signal3, QSignalEmitter.Signal4, QSignalEmitter.Signal5, QSignalEmitter.Signal6, QSignalEmitter.Signal7, QSignalEmitter.Signal8, QSignalEmitter.Signal9
 
Nested classes/interfaces inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
com.trolltech.qt.internal.QSignalEmitterInternal.AbstractSignalInternal
 
Field Summary
 QSignalEmitter.Signal0 newConnection
          This signal is emitted every time a new connection is available.
 
Fields inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
currentSender
 
Constructor Summary
QTcpServer()
          Constructs a QTcpServer object.
QTcpServer(QObject parent)
          Constructs a QTcpServer object.
 
Method Summary
 void close()
          Closes the server.
 java.lang.String errorString()
          Returns a human readable description of the last error that occurred.
 boolean hasPendingConnections()
          Returns true if the server has a pending connection; otherwise returns false.
protected  void incomingConnection(int handle)
          This virtual function is called by QTcpServer when a new connection is available.
 boolean isListening()
          Returns true if the server is currently listening for incoming connections; otherwise returns false.
 boolean listen()
          Tells the server to listen for incoming connections on address address and port port.
 boolean listen(QHostAddress address)
          Tells the server to listen for incoming connections on address address and port port.
 boolean listen(QHostAddress address, int port)
          Tells the server to listen for incoming connections on address address and port port.
 int maxPendingConnections()
          Returns the maximum number of pending accepted connections.
 QTcpSocket nextPendingConnection()
          Returns the next pending connection as a connected QTcpSocket object.
 QNetworkProxy proxy()
          Returns the network proxy for this socket.
 QHostAddress serverAddress()
          Returns the server's address if the server is listening for connections; otherwise returns QHostAddress::Null .
 QAbstractSocket.SocketError serverError()
          Returns an error code for the last error that occurred.
 int serverPort()
          Returns the server's port if the server is listening for connections; otherwise, returns 0.
 void setMaxPendingConnections(int numConnections)
          Sets the maximum number of pending accepted connections to numConnections.
 void setProxy(QNetworkProxy networkProxy)
          Sets the explicit network proxy for this socket to networkProxy.
 boolean setSocketDescriptor(int socketDescriptor)
          Sets the socket descriptor this server should use when listening for incoming connections to socketDescriptor.
 int socketDescriptor()
          Returns the native socket descriptor the server uses to listen for incoming instructions, or -1 if the server is not listening.
 QTcpServer.Result waitForNewConnection()
          This is an overloaded method provided for convenience.
 QTcpServer.Result waitForNewConnection(int msec)
          Waits for at most msec milliseconds or until an incoming connection is available.
 
Methods inherited from class com.trolltech.qt.core.QObject
childEvent, children, connectSlotsByName, customEvent, disposeLater, dumpObjectInfo, dumpObjectTree, dynamicPropertyNames, event, eventFilter, findChild, findChild, findChild, findChildren, findChildren, findChildren, findChildren, indexOfProperty, installEventFilter, isWidgetType, killTimer, moveToThread, objectName, parent, properties, property, removeEventFilter, setObjectName, setParent, setProperty, startTimer, timerEvent, toString, userProperty
 
Methods inherited from class com.trolltech.qt.QtJambiObject
dispose, disposed, equals, finalize, reassignNativeResources, tr, tr, tr
 
Methods inherited from class com.trolltech.qt.QSignalEmitter
blockSignals, disconnect, disconnect, signalsBlocked, signalSender, thread
 
Methods inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
__qt_signalInitialization
 
Methods inherited from class java.lang.Object
clone, getClass, hashCode, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface com.trolltech.qt.QtJambiInterface
disableGarbageCollection, nativeId, nativePointer, reenableGarbageCollection, setJavaOwnership
 

Field Detail

newConnection

public final QSignalEmitter.Signal0 newConnection
This signal is emitted every time a new connection is available.

See also:
hasPendingConnections(), and nextPendingConnection().

Constructor Detail

QTcpServer

public QTcpServer()
Constructs a QTcpServer object.

parent is passed to the QObject constructor.

See also:
listen(), and setSocketDescriptor().


QTcpServer

public QTcpServer(QObject parent)
Constructs a QTcpServer object.

parent is passed to the QObject constructor.

See also:
listen(), and setSocketDescriptor().

Method Detail

close

public final void close()
Closes the server. The server will no longer listen for incoming connections.

See also:
listen().


errorString

public final java.lang.String errorString()
Returns a human readable description of the last error that occurred.

See also:
serverError().


isListening

public final boolean isListening()
Returns true if the server is currently listening for incoming connections; otherwise returns false.

See also:
listen().


maxPendingConnections

public final int maxPendingConnections()
Returns the maximum number of pending accepted connections. The default is 30.

See also:
setMaxPendingConnections(), and hasPendingConnections().


proxy

public final QNetworkProxy proxy()
Returns the network proxy for this socket. By default QNetworkProxy::DefaultProxy is used.

See also:
setProxy(), and QNetworkProxy.


serverAddress

public final QHostAddress serverAddress()
Returns the server's address if the server is listening for connections; otherwise returns QHostAddress::Null .

See also:
serverPort(), and listen().


serverError

public final QAbstractSocket.SocketError serverError()
Returns an error code for the last error that occurred.

See also:
errorString().


setMaxPendingConnections

public final void setMaxPendingConnections(int numConnections)
Sets the maximum number of pending accepted connections to numConnections. QTcpServer will accept no more than numConnections incoming connections before nextPendingConnection() is called. By default, the limit is 30 pending connections.

Clients may still able to connect after the server has reached its maximum number of pending connections (i.e., QTcpSocket can still emit the connected() signal). QTcpServer will stop accepting the new connections, but the operating system may still keep them in queue.

See also:
maxPendingConnections(), and hasPendingConnections().


setProxy

public final void setProxy(QNetworkProxy networkProxy)
Sets the explicit network proxy for this socket to networkProxy.

To disable the use of a proxy for this socket, use the QNetworkProxy::NoProxy proxy type:

        server.setProxy(new QNetworkProxy(QNetworkProxy.ProxyType.NoProxy, new String(), 0));

See also:
proxy(), and QNetworkProxy.


setSocketDescriptor

public final boolean setSocketDescriptor(int socketDescriptor)
Sets the socket descriptor this server should use when listening for incoming connections to socketDescriptor. Returns true if the socket is set successfully; otherwise returns false.

The socket is assumed to be in listening state.

See also:
socketDescriptor(), and isListening().


socketDescriptor

public final int socketDescriptor()
Returns the native socket descriptor the server uses to listen for incoming instructions, or -1 if the server is not listening.

If the server is using QNetworkProxy, the returned descriptor may not be usable with native socket functions.

See also:
setSocketDescriptor(), and isListening().


hasPendingConnections

public boolean hasPendingConnections()
Returns true if the server has a pending connection; otherwise returns false.

See also:
nextPendingConnection(), and setMaxPendingConnections().


incomingConnection

protected void incomingConnection(int handle)
This virtual function is called by QTcpServer when a new connection is available. The socketDescriptor argument is the native socket descriptor for the accepted connection.

The base implementation creates a QTcpSocket, sets the socket descriptor and then stores the QTcpSocket in an internal list of pending connections. Finally newConnection() is emitted.

Reimplement this function to alter the server's behavior when a connection is available.

If this server is using QNetworkProxy then the socketDescriptor may not be usable with native socket functions, and should only be used with QTcpSocket::setSocketDescriptor().

See also:
newConnection() , and nextPendingConnection().


nextPendingConnection

public QTcpSocket nextPendingConnection()
Returns the next pending connection as a connected QTcpSocket object.

The socket is created as a child of the server, which means that it is automatically deleted when the QTcpServer object is destroyed. It is still a good idea to delete the object explicitly when you are done with it, to avoid wasting memory.

0 is returned if this function is called when there are no pending connections.

See also:
hasPendingConnections().


listen

public final boolean listen(QHostAddress address,
                            int port)
Tells the server to listen for incoming connections on address address and port port. If port is 0, a port is chosen automatically. If address is QHostAddress::Any, the server will listen on all network interfaces.

Returns true on success; otherwise returns false.


listen

public final boolean listen(QHostAddress address)
Tells the server to listen for incoming connections on address address and port port. If port is 0, a port is chosen automatically. If address is QHostAddress::Any , the server will listen on all network interfaces.

Returns true on success; otherwise returns false.

See also:
isListening().


listen

public final boolean listen()
Tells the server to listen for incoming connections on address address and port port. If port is 0, a port is chosen automatically. If address is QHostAddress::Any , the server will listen on all network interfaces.

Returns true on success; otherwise returns false.

See also:
isListening().


serverPort

public final int serverPort()
Returns the server's port if the server is listening for connections; otherwise, returns 0.


waitForNewConnection

public final QTcpServer.Result waitForNewConnection(int msec)
Waits for at most msec milliseconds or until an incoming connection is available. Returns true if a connection is available; otherwise returns false.

This is a blocking function call. Its use is not adviced in a single-threaded GUI application, since the whole application will stop responding until the function returns. waitForNewConnection() is mostly useful when there is no event loop available.

The non-blocking alternative is to connect to the newConnection() signal.


waitForNewConnection

public final QTcpServer.Result waitForNewConnection()
This is an overloaded method provided for convenience.

Returns: