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 <H1>The File Content Provider</H1>
 <H2>Preface</H2>
 <P>The File Content Provider (FCP), a Content Provider for the
 Universal ContentBroker (UCB), provides access to the local file
 system. It does this by providing file content objects, which
 represent either a directory or a file in the local file system. The
 FCP is able to restrict access to the file system to a number of
 directories shown to the client under configurable aliases.</P>
 <H2>File Contents</H2>
 <P>The FCP provides content representing either a <B>Directory</B> or
 <B>File</B> in the local file system.</P>
 <OL>
 	<LI><P>A directory contains other directories or files.</P>
 	<LI><P>A file is a container for document data/content. The FCP is
 	not able to determine the <I><FONT FACE="Courier, monospace">MediaType</FONT></I>
 	property of a file content.</P>
 </OL>
 <H2>Creation Of New File Contents</H2>
 <P>A content representing directories implements the interface
 <FONT FACE="Courier, monospace">XContentCreator</FONT>. A file
 content object supports the command &bdquo;<I><FONT FACE="Courier, monospace">in<FONT FACE="Courier, monospace">s</FONT>ert.</FONT></I>
 To create a new directory/file in a directory:</P>
 <OL>
 	<LI><P>Let the parent directory create a new content by calling its
 	<FONT FACE="Courier, monospace">createNewContent</FONT> method. The
 	content type to use for new folders is
 	<B>application/vnd.sun.staroffice.fsys-folder</B>. To create a new
 	file, use the type string <B>application/vnd.sun.staroffice.fsys-file</B>.
 	As return value you get a new file content object.</P>
 	<LI><P STYLE="font-weight: medium">Set a title at the new file
 	content object. ( Let the new child execute a <FONT FACE="Courier, monospace">setPropertyValues</FONT>
 	&ndash; command, which sets at least the property&bdquo;<I><FONT FACE="Courier, monospace">Title</FONT></I>
 	to a non-empty value ).</P>
 	<LI><P>Let the new file content object ( not the parent! ) execute
 	the command &bdquo;<I><FONT FACE="Courier, monospace">insert</FONT></I>&ldquo;.
 	This will create the corresponding physical file or directory. For
 	files, you need to supply the implementation of an <FONT FACE="Courier, monospace">XInputStream</FONT>
 	with the command's parameters, that provides access to the stream
 	data.</P>
 </OL>
 <H2>URL Schemes for File Contents</H2>
 <H3>The 'file' URL Scheme</H3>
 <P>Each file content has an identifier corresponding to the following
 scheme:</P>
 <P>file:///&lt;path&gt;</P>
 <P>where &lt;path&gt; is a hierarchical path of the form</P>
 <P>&lt;name1&gt;/&lt;name&gt;/.../&lt;name&gt;.</P>
 <P><B>The first part of &lt;path&gt; ( &lt;name1&gt; ) need not
 denote a physically existing directory, </B>but may be re-mapped to
 such a directory. If this is done, the FCP refuses file access for
 any URL whose &lt;name1&gt;-part is not an element of a predefined
 list of alias names.</P>
 <H3>The 'vnd.sun.star.wfs' URL Scheme</H3>
 <P>In the Sun ONE Webtop, the server side file system is addressed
 with vnd.sun.star.wfs URLs (wfs stands for <I>Webtop File System</I>),
 while the file URL scheme is reserved for a potential client side
 file system.</P>
 <P>In that scenario, a trick is used to completely hide the
 vnd.sun.star.wfs URL scheme from the FCP (i.e., the server side FCP
 internally works with file URLs, just like any other FCP): There is a
 special Remote Access Content Provider (RAP) between the UCB and the
 FCP. That RAP, among other things, can route requests to another UCP
 and rewrite URLs &quot;on the fly.&quot; This feature is used here,
 so that the client of the UCB works with vnd.sun.star.wfs URLs and
 the FCP remains unmodified and works with file URLs, with a RAP in
 between that maps between those two URL schemes:</P>
 <P><IMG SRC="wfs.gif" NAME="Object1" ALIGN=LEFT WIDTH=533 HEIGHT=116 BORDER=0><BR CLEAR=LEFT>Except
 for the different scheme name, the syntax of the vnd.sun.star.wfs URL
 scheme is exactly the same as that of the file URL scheme.</P>
 <H2 STYLE="page-break-before: always">Appendix</H2>
 <P>The following table gives an overview of the different properties
 of file contents and the supported commands and interfaces.</P>
 <P><BR><BR>
 </P>
 <TABLE WIDTH=100% BORDER=1 BORDERCOLOR="#000000" CELLPADDING=4 CELLSPACING=0>
 	<COL WIDTH=20*>
 	<COL WIDTH=41*>
 	<COL WIDTH=63*>
 	<COL WIDTH=59*>
 	<COL WIDTH=72*>
 	<THEAD>
 		<TR VALIGN=TOP>
 			<TH WIDTH=8%>
 				<P><BR>
 				</P>
 			</TH>
 			<TH WIDTH=16%>
 				<P>UCB Type</P>
 				<P>(returned by XContent::getContentType )</P>
 			</TH>
 			<TH WIDTH=25%>
 				<P>Properties</P>
 			</TH>
 			<TH WIDTH=23%>
 				<P>Commands</P>
 			</TH>
 			<TH WIDTH=28%>
 				<P>Interfaces</P>
 			</TH>
 		</TR>
 	</THEAD>
 	<TBODY>
 		<TR VALIGN=TOP>
 			<TD WIDTH=8%>
 				<P>File</P>
 			</TD>
 			<TD WIDTH=16%>
 				<P>application/vnd.sun.staroffice.fsys-file</P>
 			</TD>
 			<TD WIDTH=25%>
 				<P>[readonly] ContentType</P>
 				<P>DateModified</P>
 				<P>[readonly] IsDocument</P>
 				<P>[readonly] IsFolder</P>
 				<P>Size</P>
 				<P>Title</P>
 				<P>IsReadOnly</P>
 				<P>IsVolume</P>
 				<P>IsRemoveable</P>
 				<P>IsRemote</P>
 				<P>IsCompactDisc</P>
 				<P>IsFloppy</P>
 				<P>IsHidden</P>
 			</TD>
 			<TD WIDTH=23%>
 				<P>getCommandInfo</P>
 				<P>getPropertySetInfo</P>
 				<P>getPropertyValues</P>
 				<P>setPropertyValues</P>
 				<P>insert</P>
 				<P>delete</P>
 				<P>open</P>
 				<P>transfer</P>
 				<P><BR>
 				</P>
 			</TD>
 			<TD WIDTH=28%>
 				<P>lang::<B>XServiceInfo</B></P>
 				<P>lang::<B>XComponent</B></P>
 				<P>ucb::<B>XContent</B></P>
 				<P>ucb::<B>XCommandProcessor</B></P>
 				<P>beans::<B>XPropertiesChangeNotifier</B></P>
 				<P>beans::<B>XPropertyContainer</B></P>
 				<P>beans::<B>XPropertySetInfoChangeNotifier</B></P>
 				<P>ucb::<B>XCommandInfoChangeNotifier</B></P>
 				<P>container::<B>XChild</B></P>
 				<P>ucb::<B>XContentCreator</B></P>
 			</TD>
 		</TR>
 		<TR VALIGN=TOP>
 			<TD WIDTH=8%>
 				<P>Directory</P>
 			</TD>
 			<TD WIDTH=16%>
 				<P>application/vnd.sun.staroffice.fsys-folder</P>
 			</TD>
 			<TD WIDTH=25%>
 				<P>[readonly] ContentType</P>
 				<P>DateModified</P>
 				<P>[readonly] IsDocument</P>
 				<P>[readonly] IsFolder</P>
 				<P>Size</P>
 				<P>Title</P>
 				<P>IsReadOnly</P>
 				<P>IsVolume</P>
 				<P>IsRemoveable</P>
 				<P>IsRemote</P>
 				<P>IsCompactDisc</P>
 				<P>IsFloppy</P>
 				<P>IsHidden</P>
 			</TD>
 			<TD WIDTH=23%>
 				<P>getCommandInfo</P>
 				<P>getPropertySetInfo</P>
 				<P>getPropertyValues</P>
 				<P>setPropertyValues</P>
 				<P>insert</P>
 				<P>delete</P>
 				<P>open</P>
 				<P><BR><BR>
 				</P>
 				<P><BR>
 				</P>
 			</TD>
 			<TD WIDTH=28%>
 				<P>lang::<B>XServiceInfo</B></P>
 				<P>lang::<B>XComponent</B></P>
 				<P>ucb::<B>XContent</B></P>
 				<P>ucb::<B>XCommandProcessor</B></P>
 				<P>beans::<B>XPropertiesChangeNotifier</B></P>
 				<P>beans::<B>XPropertyContainer</B></P>
 				<P>beans::<B>XPropertySetInfoChangeNotifier</B></P>
 				<P>ucb::<B>XCommandInfoChangeNotifier</B></P>
 				<P>container::<B>XChild</B></P>
 				<P><BR>
 				</P>
 			</TD>
 		</TR>
 	</TBODY>
 </TABLE>
 <P><BR><BR>
 </P>
 </body>
 </HTML>
	<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
	<HTML>
	<head>
	<title>The File Content Provider</title>
	<META HTTP-EQUIV="CONTENT-TYPE" CONTENT="text/html; charset=windows-1252">
	<TITLE></TITLE>
	<META NAME="GENERATOR" CONTENT="StarOffice 6.0 (Win32)">
	<META NAME="AUTHOR" CONTENT="Kai Sommerfeld">
	<META NAME="CREATED" CONTENT="20000714;12280562">
	<META NAME="CHANGEDBY" CONTENT="Andreas Bille">
	<META NAME="CHANGED" CONTENT="20020426;15221435">
	<STYLE>
	<!--
	@page { margin: 2cm }
	TD P { margin-bottom: 0.21cm }
	H1 { margin-bottom: 0.21cm; font-family: "Arial", sans-serif; font-size: 16pt }
	P { margin-bottom: 0.21cm }
	H2 { margin-bottom: 0.21cm; font-family: "Arial", sans-serif; font-size: 14pt; font-style: italic }
	H3 { margin-bottom: 0.21cm; font-family: "Arial", sans-serif }
	TH P { margin-bottom: 0.21cm; font-style: italic }
	-->
	</STYLE>
	</head>
	<body LANG="en-US">
	<H1>The File Content Provider</H1>
	<H2>Preface</H2>
	<P>The File Content Provider (FCP), a Content Provider for the
	Universal ContentBroker (UCB), provides access to the local file
	system. It does this by providing file content objects, which
	represent either a directory or a file in the local file system. The
	FCP is able to restrict access to the file system to a number of
	directories shown to the client under configurable aliases.</P>
	<H2>File Contents</H2>
	<P>The FCP provides content representing either a <B>Directory</B> or
	<B>File</B> in the local file system.</P>
	<OL>
	<LI><P>A directory contains other directories or files.</P>
	<LI><P>A file is a container for document data/content. The FCP is
	not able to determine the <I><FONT FACE="Courier, monospace">MediaType</FONT></I>
	property of a file content.</P>
	</OL>
	<H2>Creation Of New File Contents</H2>
	<P>A content representing directories implements the interface
	<FONT FACE="Courier, monospace">XContentCreator</FONT>. A file
	content object supports the command &bdquo;<I><FONT FACE="Courier, monospace">in<FONT FACE="Courier, monospace">s</FONT>ert.</FONT></I>
	To create a new directory/file in a directory:</P>
	<OL>
	<LI><P>Let the parent directory create a new content by calling its
	<FONT FACE="Courier, monospace">createNewContent</FONT> method. The
	content type to use for new folders is
	<B>application/vnd.sun.staroffice.fsys-folder</B>. To create a new
	file, use the type string <B>application/vnd.sun.staroffice.fsys-file</B>.
	As return value you get a new file content object.</P>
	<LI><P STYLE="font-weight: medium">Set a title at the new file
	content object. ( Let the new child execute a <FONT FACE="Courier, monospace">setPropertyValues</FONT>
	– command, which sets at least the property&bdquo;<I><FONT FACE="Courier, monospace">Title</FONT></I>
	to a non-empty value ).</P>
	<LI><P>Let the new file content object ( not the parent! ) execute
	the command &bdquo;<I><FONT FACE="Courier, monospace">insert</FONT></I>“.
	This will create the corresponding physical file or directory. For
	files, you need to supply the implementation of an <FONT FACE="Courier, monospace">XInputStream</FONT>
	with the command's parameters, that provides access to the stream
	data.</P>
	</OL>
	<H2>URL Schemes for File Contents</H2>
	<H3>The 'file' URL Scheme</H3>
	<P>Each file content has an identifier corresponding to the following
	scheme:</P>
	<P>file:///<path></P>
	<P>where <path> is a hierarchical path of the form</P>
	<P><name1>/<name>/.../<name>.</P>
	<P><B>The first part of <path> ( <name1> ) need not
	denote a physically existing directory, </B>but may be re-mapped to
	such a directory. If this is done, the FCP refuses file access for
	any URL whose <name1>-part is not an element of a predefined
	list of alias names.</P>
	<H3>The 'vnd.sun.star.wfs' URL Scheme</H3>
	<P>In the Sun ONE Webtop, the server side file system is addressed
	with vnd.sun.star.wfs URLs (wfs stands for <I>Webtop File System</I>),
	while the file URL scheme is reserved for a potential client side
	file system.</P>
	<P>In that scenario, a trick is used to completely hide the
	vnd.sun.star.wfs URL scheme from the FCP (i.e., the server side FCP
	internally works with file URLs, just like any other FCP): There is a
	special Remote Access Content Provider (RAP) between the UCB and the
	FCP. That RAP, among other things, can route requests to another UCP
	and rewrite URLs "on the fly." This feature is used here,
	so that the client of the UCB works with vnd.sun.star.wfs URLs and
	the FCP remains unmodified and works with file URLs, with a RAP in
	between that maps between those two URL schemes:</P>
	<P><IMG SRC="wfs.gif" NAME="Object1" ALIGN=LEFT WIDTH=533 HEIGHT=116 BORDER=0><BR CLEAR=LEFT>Except
	for the different scheme name, the syntax of the vnd.sun.star.wfs URL
	scheme is exactly the same as that of the file URL scheme.</P>
	<H2 STYLE="page-break-before: always">Appendix</H2>
	<P>The following table gives an overview of the different properties
	of file contents and the supported commands and interfaces.</P>
	<P><BR><BR>
	</P>
	<TABLE WIDTH=100% BORDER=1 BORDERCOLOR="#000000" CELLPADDING=4 CELLSPACING=0>
	<COL WIDTH=20*>
	<COL WIDTH=41*>
	<COL WIDTH=63*>
	<COL WIDTH=59*>
	<COL WIDTH=72*>
	<THEAD>
	<TR VALIGN=TOP>
	<TH WIDTH=8%>
	<P><BR>
	</P>
	</TH>
	<TH WIDTH=16%>
	<P>UCB Type</P>
	<P>(returned by XContent::getContentType )</P>
	</TH>
	<TH WIDTH=25%>
	<P>Properties</P>
	</TH>
	<TH WIDTH=23%>
	<P>Commands</P>
	</TH>
	<TH WIDTH=28%>
	<P>Interfaces</P>
	</TH>
	</TR>
	</THEAD>
	<TBODY>
	<TR VALIGN=TOP>
	<TD WIDTH=8%>
	<P>File</P>
	</TD>
	<TD WIDTH=16%>
	<P>application/vnd.sun.staroffice.fsys-file</P>
	</TD>
	<TD WIDTH=25%>
	<P>[readonly] ContentType</P>
	<P>DateModified</P>
	<P>[readonly] IsDocument</P>
	<P>[readonly] IsFolder</P>
	<P>Size</P>
	<P>Title</P>
	<P>IsReadOnly</P>
	<P>IsVolume</P>
	<P>IsRemoveable</P>
	<P>IsRemote</P>
	<P>IsCompactDisc</P>
	<P>IsFloppy</P>
	<P>IsHidden</P>
	</TD>
	<TD WIDTH=23%>
	<P>getCommandInfo</P>
	<P>getPropertySetInfo</P>
	<P>getPropertyValues</P>
	<P>setPropertyValues</P>
	<P>insert</P>
	<P>delete</P>
	<P>open</P>
	<P>transfer</P>
	<P><BR>
	</P>
	</TD>
	<TD WIDTH=28%>
	<P>lang::<B>XServiceInfo</B></P>
	<P>lang::<B>XComponent</B></P>
	<P>ucb::<B>XContent</B></P>
	<P>ucb::<B>XCommandProcessor</B></P>
	<P>beans::<B>XPropertiesChangeNotifier</B></P>
	<P>beans::<B>XPropertyContainer</B></P>
	<P>beans::<B>XPropertySetInfoChangeNotifier</B></P>
	<P>ucb::<B>XCommandInfoChangeNotifier</B></P>
	<P>container::<B>XChild</B></P>
	<P>ucb::<B>XContentCreator</B></P>
	</TD>
	</TR>
	<TR VALIGN=TOP>
	<TD WIDTH=8%>
	<P>Directory</P>
	</TD>
	<TD WIDTH=16%>
	<P>application/vnd.sun.staroffice.fsys-folder</P>
	</TD>
	<TD WIDTH=25%>
	<P>[readonly] ContentType</P>
	<P>DateModified</P>
	<P>[readonly] IsDocument</P>
	<P>[readonly] IsFolder</P>
	<P>Size</P>
	<P>Title</P>
	<P>IsReadOnly</P>
	<P>IsVolume</P>
	<P>IsRemoveable</P>
	<P>IsRemote</P>
	<P>IsCompactDisc</P>
	<P>IsFloppy</P>
	<P>IsHidden</P>
	</TD>
	<TD WIDTH=23%>
	<P>getCommandInfo</P>
	<P>getPropertySetInfo</P>
	<P>getPropertyValues</P>
	<P>setPropertyValues</P>
	<P>insert</P>
	<P>delete</P>
	<P>open</P>
	<P><BR><BR>
	</P>
	<P><BR>
	</P>
	</TD>
	<TD WIDTH=28%>
	<P>lang::<B>XServiceInfo</B></P>
	<P>lang::<B>XComponent</B></P>
	<P>ucb::<B>XContent</B></P>
	<P>ucb::<B>XCommandProcessor</B></P>
	<P>beans::<B>XPropertiesChangeNotifier</B></P>
	<P>beans::<B>XPropertyContainer</B></P>
	<P>beans::<B>XPropertySetInfoChangeNotifier</B></P>
	<P>ucb::<B>XCommandInfoChangeNotifier</B></P>
	<P>container::<B>XChild</B></P>
	<P><BR>
	</P>
	</TD>
	</TR>
	</TBODY>
	</TABLE>
	<P><BR><BR>
	</P>
	</body>
	</HTML>