/*
* =============================================================================
*
* Copyright (c) 2011-2014, The THYMELEAF team (http://www.thymeleaf.org)
*
* 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.thymeleaf.resourceresolver;
import java.io.InputStream;
import javax.servlet.ServletContext;
import org.thymeleaf.TemplateProcessingParameters;
import org.thymeleaf.context.IContext;
import org.thymeleaf.context.IWebContext;
import org.thymeleaf.exceptions.TemplateProcessingException;
import org.thymeleaf.util.Validate;
/**
* <p>
* Implementation of {@link IResourceResolver} that resolves
* resources as servlet context resources:
* </p>
* <p>
* <tt>
* servletContext.getResourceAsStream(resourceName)
* </tt>
* </p>
*
* @author Daniel Fernández
*
* @since 1.0
*
*/
public final class ServletContextResourceResolver
implements IResourceResolver {
public static final String NAME = "SERVLETCONTEXT";
public ServletContextResourceResolver() {
super();
}
public String getName() {
return NAME;
}
public InputStream getResourceAsStream(final TemplateProcessingParameters templateProcessingParameters, final String resourceName) {
Validate.notNull(templateProcessingParameters, "Template Processing Parameters cannot be null");
Validate.notNull(resourceName, "Resource name cannot be null");
final IContext context = templateProcessingParameters.getContext();
if (!(context instanceof IWebContext)) {
throw new TemplateProcessingException(
"Resource resolution by ServletContext with " +
this.getClass().getName() + " can only be performed " +
"when context implements " + IWebContext.class.getName() +
" [current context: " + context.getClass().getName() + "]");
}
final ServletContext servletContext =
((IWebContext)context).getServletContext();
if (servletContext == null) {
throw new TemplateProcessingException("Thymeleaf context returned a null ServletContext");
}
return servletContext.getResourceAsStream(resourceName);
}
}