com.vaadin.server

Class AbstractExtension

java.lang.Object

com.vaadin.server.AbstractClientConnector

com.vaadin.server.AbstractExtension

All Implemented Interfaces:

MethodEventSource, ClientConnector, Extension, Connector, Serializable

Direct Known Subclasses:

AbstractJavaScriptExtension, BrowserWindowOpener, FileDownloader, Grid.AbstractGridExtension, JavaScript, Responsive, RpcDataProviderExtension

public abstract class AbstractExtension
extends AbstractClientConnector
implements Extension

An extension is an entity that is attached to a Component or another Extension and independently communicates between client and server.

Extensions can use shared state and RPC in the same way as components.

AbstractExtension adds a mechanism for adding the extension to any Connector (extend). To let the Extension determine what kind target it can be added to, the extend method is declared as protected.

Since:

7.0.0

Author:

Vaadin Ltd

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface com.vaadin.server.ClientConnector

ClientConnector.AttachEvent, ClientConnector.AttachListener, ClientConnector.ConnectorErrorEvent, ClientConnector.DetachEvent, ClientConnector.DetachListener

Constructor Summary

Constructors

Constructor and Description
AbstractExtension() Creates a new extension instance without extending any connector.
AbstractExtension(AbstractClientConnector target) Creates a new extension instance that extends the provided connector.

Method Summary

Modifier and Type	Method and Description
protected void	extend(AbstractClientConnector target) Add this extension to the target connector.
ClientConnector	getParent() Gets the parent connector of this connector, or null if the connector is not attached to any parent.
protected Class<? extends ClientConnector>	getSupportedParentType() Gets a type that the parent must be an instance of.
void	remove() Remove this extension from its target.
void	setParent(ClientConnector parent) Sets the parent connector of the connector.

Methods inherited from class com.vaadin.server.AbstractClientConnector

addAttachListener, addDetachListener, addExtension, addListener, addListener, addListener, addMethodInvocationToQueue, attach, beforeClientResponse, createState, detach, encodeState, equals, fireEvent, getAllChildrenIterable, getConnectorId, getErrorHandler, getExtensions, getListeners, getResource, getRpcManager, getRpcProxy, getSession, getState, getState, getStateType, getUI, handleConnectorRequest, hashCode, hasListeners, isAttached, isConnectorEnabled, isThis, markAsDirty, markAsDirtyRecursive, registerRpc, registerRpc, removeAttachListener, removeDetachListener, removeExtension, removeListener, removeListener, removeListener, removeListener, requestRepaint, requestRepaintAll, retrievePendingRpcCalls, setErrorHandler, setResource

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.vaadin.server.ClientConnector

addAttachListener, addDetachListener, attach, beforeClientResponse, detach, encodeState, getErrorHandler, getExtensions, getRpcManager, getStateType, getUI, handleConnectorRequest, isAttached, isConnectorEnabled, markAsDirty, markAsDirtyRecursive, removeAttachListener, removeDetachListener, removeExtension, requestRepaint, requestRepaintAll, retrievePendingRpcCalls, setErrorHandler

Methods inherited from interface com.vaadin.shared.Connector

getConnectorId

Constructor Detail

AbstractExtension

public AbstractExtension()

Creates a new extension instance without extending any connector.

AbstractExtension

public AbstractExtension(AbstractClientConnector target)

Creates a new extension instance that extends the provided connector.

Parameters:

target - the connector to extend

Since:

7.4

Method Detail

getSupportedParentType

protected Class<? extends ClientConnector> getSupportedParentType()

Gets a type that the parent must be an instance of. Override this if the extension only support certain targets, e.g. if only TextFields can be extended.

Returns:

a type that the parent must be an instance of

extend

protected void extend(AbstractClientConnector target)

Add this extension to the target connector. This method is protected to allow subclasses to require a more specific type of target.

Parameters:

target - the connector to attach this extension to

remove

public void remove()

Description copied from interface: Extension

Remove this extension from its target. After an extension has been removed, it cannot be attached again.

Specified by:

remove in interface Extension

setParent

public void setParent(ClientConnector parent)

Description copied from interface: Extension

Sets the parent connector of the connector. This method automatically calls ClientConnector.attach() if the connector becomes attached to the session.

This method is rarely called directly. AbstractClientConnector.addExtension(Extension) is normally used for adding extensions to a parent and it will call this method implicitly.

Specified by:

setParent in interface Extension

Parameters:

parent - the parent connector

getParent

public ClientConnector getParent()

Description copied from interface: Connector

Gets the parent connector of this connector, or null if the connector is not attached to any parent.

Specified by:

getParent in interface ClientConnector

Specified by:

getParent in interface Connector

Returns:

the parent connector, or null if there is no parent.