org.springframework.ui.velocity.SpringResourceLoader 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.IOException;
import java.io.InputStream;
import java.util.Arrays;
import org.apache.commons.collections.ExtendedProperties;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.apache.velocity.runtime.resource.Resource;
import org.apache.velocity.runtime.resource.loader.ResourceLoader;
import org.springframework.util.StringUtils;
/**
* Velocity ResourceLoader adapter that loads via a Spring ResourceLoader.
* Used by VelocityEngineFactory for any resource loader path that cannot
* be resolved to a java.io.File.
*
* Note that this loader does not allow for modification detection:
* Use Velocity's default FileResourceLoader for java.io.File
* resources.
*
*
Expects "spring.resource.loader" and "spring.resource.loader.path"
* application attributes in the Velocity runtime: the former of type
* org.springframework.core.io.ResourceLoader, the latter a String.
*
* @author Juergen Hoeller
* @since 14.03.2004
* @see VelocityEngineFactory#setResourceLoaderPath
* @see org.springframework.core.io.ResourceLoader
* @see org.apache.velocity.runtime.resource.loader.FileResourceLoader
*/
public class SpringResourceLoader extends ResourceLoader {
public static final String NAME = "spring";
public static final String SPRING_RESOURCE_LOADER_CLASS = "spring.resource.loader.class";
public static final String SPRING_RESOURCE_LOADER_CACHE = "spring.resource.loader.cache";
public static final String SPRING_RESOURCE_LOADER = "spring.resource.loader";
public static final String SPRING_RESOURCE_LOADER_PATH = "spring.resource.loader.path";
protected final Log logger = LogFactory.getLog(getClass());
private org.springframework.core.io.ResourceLoader resourceLoader;
private String[] resourceLoaderPaths;
public void init(ExtendedProperties configuration) {
this.resourceLoader = (org.springframework.core.io.ResourceLoader)
this.rsvc.getApplicationAttribute(SPRING_RESOURCE_LOADER);
String resourceLoaderPath = (String) this.rsvc.getApplicationAttribute(SPRING_RESOURCE_LOADER_PATH);
if (this.resourceLoader == null) {
throw new IllegalArgumentException(
"'resourceLoader' application attribute must be present for SpringResourceLoader");
}
if (resourceLoaderPath == null) {
throw new IllegalArgumentException(
"'resourceLoaderPath' application attribute must be present for SpringResourceLoader");
}
this.resourceLoaderPaths = StringUtils.commaDelimitedListToStringArray(resourceLoaderPath);
for (int i = 0; i < this.resourceLoaderPaths.length; i++) {
String path = this.resourceLoaderPaths[i];
if (!path.endsWith("/")) {
this.resourceLoaderPaths[i] = path + "/";
}
}
if (logger.isInfoEnabled()) {
logger.info("SpringResourceLoader for Velocity: using resource loader [" + this.resourceLoader +
"] and resource loader paths " + Arrays.asList(this.resourceLoaderPaths));
}
}
public InputStream getResourceStream(String source) throws ResourceNotFoundException {
if (logger.isDebugEnabled()) {
logger.debug("Looking for Velocity resource with name [" + source + "]");
}
for (int i = 0; i < this.resourceLoaderPaths.length; i++) {
org.springframework.core.io.Resource resource =
this.resourceLoader.getResource(this.resourceLoaderPaths[i] + source);
try {
return resource.getInputStream();
}
catch (IOException ex) {
if (logger.isDebugEnabled()) {
logger.debug("Could not find Velocity resource: " + resource);
}
}
}
throw new ResourceNotFoundException(
"Could not find resource [" + source + "] in Spring resource loader path");
}
public boolean isSourceModified(Resource resource) {
return false;
}
public long getLastModified(Resource resource) {
return 0;
}
}