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/*
* Copyright 2000-2001,2004 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import org.apache.velocity.app.Velocity;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.Template;
import org.apache.velocity.exception.ParseErrorException;
import org.apache.velocity.exception.ResourceNotFoundException;
import java.io.*;
import java.util.ArrayList;
/**
* This class is a simple demonstration of how the Velocity Template Engine
* can be used in a standalone application.
*
* @author <a href="mailto:jvanzyl@apache.org">Jason van Zyl</a>
* @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
* @version $Id: Example.java,v 1.4.8.1 2004/03/04 00:18:29 geirm Exp $
*/
public class Example
{
public Example(String templateFile)
{
try
{
/*
* setup
*/
Velocity.init("./src/velocity.properties");
/*
* Make a context object and populate with the data. This
* is where the Velocity engine gets the data to resolve the
* references (ex. $list) in the template
*/
VelocityContext context = new VelocityContext();
context.put("list", getNames());
/*
* get the Template object. This is the parsed version of your
* template input file. Note that getTemplate() can throw
* ResourceNotFoundException : if it doesn't find the template
* ParseErrorException : if there is something wrong with the VTL
* Exception : if something else goes wrong (this is generally
* indicative of as serious problem...)
*/
Template template = null;
try
{
template = Velocity.getTemplate(templateFile);
}
catch( ResourceNotFoundException rnfe )
{
System.out.println("Example : error : cannot find template " + templateFile );
}
catch( ParseErrorException pee )
{
System.out.println("Example : Syntax error in template " + templateFile + ":" + pee );
}
/*
* Now have the template engine process your template using the
* data placed into the context. Think of it as a 'merge'
* of the template and the data to produce the output stream.
*/
BufferedWriter writer = writer = new BufferedWriter(
new OutputStreamWriter(System.out));
if ( template != null)
template.merge(context, writer);
/*
* flush and cleanup
*/
writer.flush();
writer.close();
}
catch( Exception e )
{
System.out.println(e);
}
}
public ArrayList getNames()
{
ArrayList list = new ArrayList();
list.add("ArrayList element 1");
list.add("ArrayList element 2");
list.add("ArrayList element 3");
list.add("ArrayList element 4");
return list;
}
public static void main(String[] args)
{
Example t = new Example("./src/example.vm");
}
}
-------------------------------------------------------------------------------------
## This is an example velocity template
#set( $this = "Velocity")
$this is great!
#foreach( $name in $list )
$name is great!
#end
#set( $condition = true)
#if ($condition)
The condition is true!
#else
The condition is false!
#end
-------------------------------------------------------------------------------------
#
# This is a simple example of a velocity properties file.
#
# Any property that is not listed here will have it's default
# value used. The default values are located in :
# * src/java/org/apache/velocity/runtime/default/velocity.defaults
# * http://jakarta.apache.org/velocity/developer-guide.html
#
# as an example, we are changing the name of the velocity log
#
runtime.log = velocity_example.log
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