org.springframework.ui.velocity.VelocityEngineUtils Maven / Gradle / Ivy
/*
* Copyright 2002-2006 the original author or authors.
*
* 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.
*/
package org.springframework.ui.velocity;
import java.io.StringWriter;
import java.io.Writer;
import java.util.Map;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.VelocityEngine;
import org.apache.velocity.exception.VelocityException;
/**
* Utility class for working with a VelocityEngine.
* Provides convenience methods to merge a Velocity template with a model.
*
* @author Juergen Hoeller
* @since 22.01.2004
*/
public abstract class VelocityEngineUtils {
private static final Log logger = LogFactory.getLog(VelocityEngineUtils.class);
/**
* Merge the specified Velocity template with the given model and write
* the result to the given Writer.
* @param velocityEngine VelocityEngine to work with
* @param templateLocation the location of template, relative to Velocity's
* resource loader path
* @param model the Map that contains model names as keys and model objects
* as values
* @param writer the Writer to write the result to
* @throws VelocityException if the template wasn't found or rendering failed
*/
public static void mergeTemplate(
VelocityEngine velocityEngine, String templateLocation, Map model, Writer writer)
throws VelocityException {
try {
VelocityContext velocityContext = new VelocityContext(model);
velocityEngine.mergeTemplate(templateLocation, velocityContext, writer);
}
catch (VelocityException ex) {
throw ex;
}
catch (RuntimeException ex) {
throw ex;
}
catch (Exception ex) {
logger.error("Why does VelocityEngine throw a generic checked exception, after all?", ex);
throw new VelocityException(ex.toString());
}
}
/**
* Merge the specified Velocity template with the given model and write
* the result to the given Writer.
* @param velocityEngine VelocityEngine to work with
* @param templateLocation the location of template, relative to Velocity's
* resource loader path
* @param encoding the encoding of the template file
* @param model the Map that contains model names as keys and model objects
* as values
* @param writer the Writer to write the result to
* @throws VelocityException if the template wasn't found or rendering failed
*/
public static void mergeTemplate(
VelocityEngine velocityEngine, String templateLocation, String encoding, Map model, Writer writer)
throws VelocityException {
try {
VelocityContext velocityContext = new VelocityContext(model);
velocityEngine.mergeTemplate(templateLocation, encoding, velocityContext, writer);
}
catch (VelocityException ex) {
throw ex;
}
catch (RuntimeException ex) {
throw ex;
}
catch (Exception ex) {
logger.error("Why does VelocityEngine throw a generic checked exception, after all?", ex);
throw new VelocityException(ex.toString());
}
}
/**
* Merge the specified Velocity template with the given model into a String.
* When using this method to prepare a text for a mail to be sent with Spring's
* mail support, consider wrapping VelocityException in MailPreparationException.
* @param velocityEngine VelocityEngine to work with
* @param templateLocation the location of template, relative to Velocity's
* resource loader path
* @param model the Map that contains model names as keys and model objects
* as values
* @return the result as String
* @throws VelocityException if the template wasn't found or rendering failed
* @see org.springframework.mail.MailPreparationException
*/
public static String mergeTemplateIntoString(
VelocityEngine velocityEngine, String templateLocation, Map model)
throws VelocityException {
StringWriter result = new StringWriter();
mergeTemplate(velocityEngine, templateLocation, model, result);
return result.toString();
}
/**
* Merge the specified Velocity template with the given model into a String.
*
When using this method to prepare a text for a mail to be sent with Spring's
* mail support, consider wrapping VelocityException in MailPreparationException.
* @param velocityEngine VelocityEngine to work with
* @param templateLocation the location of template, relative to Velocity's
* resource loader path
* @param encoding the encoding of the template file
* @param model the Map that contains model names as keys and model objects
* as values
* @return the result as String
* @throws VelocityException if the template wasn't found or rendering failed
* @see org.springframework.mail.MailPreparationException
*/
public static String mergeTemplateIntoString(
VelocityEngine velocityEngine, String templateLocation, String encoding, Map model)
throws VelocityException {
StringWriter result = new StringWriter();
mergeTemplate(velocityEngine, templateLocation, encoding, model, result);
return result.toString();
}
}