JFile Enterprise Edition (JFileEE) includes resumable downloading and resumable uploading. In a resumable download, if the download fails, JFile will display a pop-up dialog containing an error message, a "Resume" button, and a "Cancel" button. If the user clicks "Resume," JFile will try to download the file again.

To enable resumable downloading, set the parameter ManuallyResumable to 1. This parameter is set to 0 (disabled) by default.

The following is a simple resumable download script:

<APPLET codebase="/JFileScripts" code="softartisans.filetransfer.UploadClient.class" 
height="0" width="0" mayscript archive="filetransfer.jar" name="fileupload">

	<!-- Microsoft JVMs will load the applet from the CAB and Sun JVMs will load -->
	<!-- from the JAR.  This CABBASE paramater is necessary for Microsoft JVMs. -->
	<PARAM name="cabbase" value="filetransfer.cab">
			
	<!-- The file at URL1 will be downloaded and saved to the path set by FileName1. -->
	<!-- To download more than one file, use URL2/FileName2, URL3/FileName3, etc. -->
	<PARAM name="URL1" value="http://localhost/images/jfile.gif">
	<PARAM name="Filename1" value="C:\jfile.gif">

	<!-- Set ManuallyResumable to 1 to be prompted to retry a download if it fails. -->
	<PARAM name="ManuallyResumable" value="1">

	<!-- This param is used for this sample only.  It is here to force a failure -->
	<!-- in order to demonstrate resumability.  Remove the CloseDownloadAfterByte param -->
	<!-- from your JFile application or else it will fail -->
	<PARAM name="CloseDownloadAfterByte" value="500">
		
</APPLET>

To demonstrate a resumable download, this script uses the parameter CloseDownloadAfterByte to force a download failure. In a resumable download, this parameter takes effect only for the first download request. It will not affect subsequent resume download requests. Do not include this parameter in a real-world resumable download application.

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