geirm 00/11/05 20:10:19
Added: src/java/org/apache/velocity/runtime/directive Include.java
Log:
Include Pluggable Directive to support #include() functionality.
Revision Changes Path
1.1
jakarta-velocity/src/java/org/apache/velocity/runtime/directive/Include.java
Index: Include.java
===================================================================
package org.apache.velocity.runtime.directive;
/*
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowlegement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact [EMAIL PROTECTED]
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Group.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
import java.io.*;
import org.apache.velocity.runtime.parser.*;
import org.apache.velocity.Context;
import org.apache.velocity.runtime.Runtime;
import org.apache.velocity.runtime.parser.node.Node;
/**
* Pluggable directive that handles the #include() statement in VTL.
* This #include() can take multiple arguments of either StringLiteral or Reference.
*
* Notes:
* -----
* 1) The included source material can only come from somewhere in
* the TemplateRoot tree for security reasons. There is no way
* around this. If you want to include content from elsewhere on
* your disk, use a link from somwhere under Template Root to that
* content.
*
* 2) By default, there is no output to the render stream in the event of
* a problem. You can override this behavior with two property values :
* include.output.errormsg.start
* include.output.errormsg.end
* If both are defined in velocity.properties, they will be used to
* in the render output to bracket the arg string that caused the
* problem.
* Ex. : if you are working in html then
* include.output.errormsg.start=<!-- #include error :
* include.output.errormsg.end= -->
* might be an excellent way to start...
*
* 3) As noted above, #include() can take multiple arguments.
* Ex : #include( "foo.vm" "bar.vm" $foo )
* will simply include all three if valid to output w/o any
* special separator.
*
* @author <a href="mailto:[EMAIL PROTECTED]">Geir Magnusson Jr.</a>
* @version $Id: Include.java,v 1.1 2000/11/06 04:10:19 geirm Exp $
*/
public class Include extends Directive
{
private static String ERRORMSG_START = "include.output.errormsg.start";
private static String ERRORMSG_END = "include.output.errormsg.end";
public String getName()
{
return "include";
}
public int getType()
{
return LINE;
}
/**
* iterates through the argument list and renders every
* argument that is appropriate. Any non appropriate
* arguments are logged, but render() continues.
*/
public boolean render(Context context, Writer writer, Node node)
throws IOException
{
/*
* get our arguments and check them
*/
int iArgCount = node.jjtGetNumChildren();
for( int i = 0; i < iArgCount; i++)
{
/*
* we only handle StringLiterals and References right now
*/
String strArgType = node.jjtGetChild(i).toString();
if (strArgType.equals("StringLiteral") || strArgType.equals("Reference"))
{
if (!renderOutput( node.jjtGetChild(i), context, writer ))
outputErrorToStream( writer, "error with arg " + i + " please
see log.");
}
else
{
Runtime.error( new String("#include() error : invalid argument type
: " + strArgType) );
outputErrorToStream( writer, "error with arg " + i + " please see
log.");
}
}
return true;
}
/**
* does the actual rendering of the included file
*
* @param node AST argument of type StringLiteral or Reference
* @param context valid context so we can render References
* @param writer output Writer
* @return boolean success or failure. failures are logged
*/
private boolean renderOutput( Node argNode, Context context, Writer writer )
throws IOException
{
String strArg = "";
if (argNode == null)
{
Runtime.error( new String("#include() error : null argument") );
return false;
}
/*
* does it have a value? If you have a null reference, then no.
*/
Object value = argNode.value( context );
if ( value == null)
{
Runtime.error( new String("#include() error : null argument") );
return false;
}
/*
* get the path
*/
strArg = value.toString();
/*
* everything must be under the template root TEMPLATE_PATH
*/
String strTemplatePath = Runtime.getString(Runtime.TEMPLATE_PATH);
/*
* for security, we will not accept anything with .. in the path
*/
if ( strArg.indexOf("..") != -1)
{
Runtime.error( new String("#include() error : argument " + strArg + "
contains .. and may be trying to access content outside of template root. Rejected.")
);
return false;
}
/*
* if a / leads off, then just nip that :)
*/
if ( strArg.startsWith( "/") )
strArg = strArg.substring(1);
/*
* we will put caching here in the future...
*/
File file = new File(strTemplatePath, strArg);;
try
{
BufferedReader reader = new BufferedReader( new
FileReader(file.getAbsolutePath()));
char buf[] = new char[1024];
int iLen = 0;
while ( ( iLen = reader.read( buf, 0, 1024 )) != -1)
writer.write( buf,0,iLen );
}
catch ( FileNotFoundException e )
{
Runtime.error( new String("#include() : " + e ));
return false;
}
return true;
}
/**
* Puts a message to the render output stream if ERRORMSG_START / END
* are valid property strings. Mainly used for end-user template
* debugging.
*/
private void outputErrorToStream( Writer writer, String msg )
throws IOException
{
String strOutputMsgStart = Runtime.getString( ERRORMSG_START);
String strOutputMsgEnd = Runtime.getString( ERRORMSG_END );
if ( strOutputMsgStart != null && strOutputMsgEnd != null)
{
writer.write( strOutputMsgStart + " " + msg + " " + strOutputMsgEnd );
}
return;
}
}
