Velocity 101

JohnMunsch (John Munsch) — Tue, 28 Feb 2006 03:39:13 GMT

// The most basic use of the Velocity library. You pass in a Velocity context
// containing key-value pairs and the name of a Velocity template file. It
// returns a string containing the boilerplate text generated from combining
// the two.



// Copyright (c) 2002, John Munsch

// All rights reserved.

//

// Redistribution and use in source and binary forms, with or without 

// modification, are permitted provided that the following conditions are met:

//

//     * Redistributions of source code must retain the above copyright notice, 

//       this list of conditions and the following disclaimer.

// 

//     * 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.

// 

//     * Neither the name of the John Munsch nor the names of its contributors 

//       may be used to endorse or promote products derived from this software 

//       without specific prior written permission.

//

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 

// AND ANY EXPRESS 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 COPYRIGHT OWNER OR 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.

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package com.johnmunsch.util;



import java.io.StringWriter;



import org.apache.log4j.*;

import org.apache.velocity.*;

import org.apache.velocity.app.Velocity;

import org.apache.velocity.exception.*;



/**

 * Boilerplate puts together context information and a template and produces an

 * output string that has all the replacements done in it.

 */

public class Boilerplate {

    private static Logger log = Logger.getLogger(Boilerplate.class.getName());

    

    public static String apply(VelocityContext context,

            String templateFilename) throws Exception {

        Template template = null;

        StringWriter sw = new StringWriter();



        Velocity.init();



        try {

            template = Velocity.getTemplate(templateFilename);



            template.merge(context, sw);

        } catch (ResourceNotFoundException rnfe) {

            log.error("Could not find the named template file.", rnfe);

            throw rnfe;

        } catch (ParseErrorException pee) {

            log.error("Error in the template file.", pee);

            throw pee;

        } catch (MethodInvocationException mie) {

            log.error("Error in function called by the template file.", mie);

            throw mie;

        }

       

        return sw.toString();

    }

}

DZone Snippets: boilerplate code

Velocity 101