Package com.vaadin.flow.server.streams

Class ServletResourceDownloadHandler

java.lang.Object

com.vaadin.flow.server.streams.TransferProgressAwareHandler<DownloadEvent,R>

com.vaadin.flow.server.streams.AbstractDownloadHandler<ServletResourceDownloadHandler>

com.vaadin.flow.server.streams.ServletResourceDownloadHandler

All Implemented Interfaces:

DownloadHandler, ElementRequestHandler, Serializable

public class ServletResourceDownloadHandler
extends AbstractDownloadHandler<ServletResourceDownloadHandler>

Download handler for serving a servlet resource for client download.

For instance for the file webapp/WEB-INF/servlet.json the path would be /WEB-INF/servlet.json

Since:

24.8

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
ServletResourceDownloadHandler(String path)	Create download handler for servlet resource.
ServletResourceDownloadHandler(String path, String fileNameOverride)	Create download handler for servlet resource.

Method Summary

Modifier and Type	Method	Description
String	getUrlPostfix()	Optional URL postfix allows appending an application-controlled string, e.g.
void	handleDownloadRequest(DownloadEvent downloadEvent)	Method that is called when the client wants to download from the url stored for this specific handler registration.

Methods inherited from class com.vaadin.flow.server.streams.AbstractDownloadHandler

getContentType, getTransferContext, inline, isInline

Methods inherited from class com.vaadin.flow.server.streams.TransferProgressAwareHandler

addTransferProgressListener, getListeners, notifyError, onProgress, onProgress, onProgress, onProgress, whenComplete, whenComplete, whenStart, whenStart

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.vaadin.flow.server.streams.DownloadHandler

handleRequest

Methods inherited from interface com.vaadin.flow.server.streams.ElementRequestHandler

getDisabledUpdateMode, isAllowInert

Constructor Details

ServletResourceDownloadHandler

public ServletResourceDownloadHandler(String path)

Create download handler for servlet resource. Uses url postfix as file name from path.

The downloaded file name and download URL postfix will be set to the file name from path. If you want to use a different file name, use ServletResourceDownloadHandler(String, String) instead.

Parameters:

path - path of servlet resource

ServletResourceDownloadHandler

public ServletResourceDownloadHandler(String path,
 String fileNameOverride)

Create download handler for servlet resource.

The downloaded file fileNameOverride and download URL postfix will be set to fileNameOverride.

Parameters:

path - path of servlet resource

fileNameOverride - download file name that overrides the name taken from path and also used as a download request URL postfix

Method Details

handleDownloadRequest

public void handleDownloadRequest(DownloadEvent downloadEvent)
                           throws IOException

Description copied from interface: DownloadHandler

Method that is called when the client wants to download from the url stored for this specific handler registration.

Parameters:

downloadEvent - download event containing the necessary data for writing the response

Throws:

IOException - if an IO error occurred during download

getUrlPostfix

public String getUrlPostfix()

Description copied from interface: ElementRequestHandler

Optional URL postfix allows appending an application-controlled string, e.g. the logical name of the target file, to the end of the otherwise random-looking download URL. If defined, requests that would otherwise be routable are still rejected if the postfix is missing or invalid. Postfix changes the last segment in the resource url.

Returns:

String optional URL postfix, or null for "".