/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.wicket.resource;
import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.attribute.BasicFileAttributes;
import org.apache.wicket.Application;
import org.apache.wicket.WicketRuntimeException;
import org.apache.wicket.request.cycle.RequestCycle;
import org.apache.wicket.request.resource.AbstractResource;
import org.apache.wicket.request.resource.PartWriterCallback;
/**
* Used to provide resources based on the on Java NIO FileSystem API.<br>
* <br>
* For more information see {@link FileSystemResourceReference}
*
* @author Tobias Soloschenko
*
*/
public class FileSystemResource extends AbstractResource
{
private static final long serialVersionUID = 1L;
private Path path;
/**
* Creates a new file system resource based on the given path
*
* @param path
* the path to be read for the resource
*/
public FileSystemResource(Path path)
{
this.path = path;
}
/**
* Creates a new file system resource
*
*/
public FileSystemResource()
{
this(null);
}
/**
* Creates a new resource response and reads the given path
*/
@Override
protected ResourceResponse newResourceResponse(Attributes attributes)
{
return createResourceResponse(attributes, path);
}
/**
* Creates a resource response based on the given attributes
*
* @param path
* the path to create the resource response with
* @param attributes
* request attributes
* @return the actual resource response
*/
protected ResourceResponse createResourceResponse(Attributes attributes, Path path)
{
try
{
if (path == null)
{
throw new WicketRuntimeException(
"Please override #newResourceResponse() and provide a path if using a constructor which doesn't take one as argument.");
}
this.path = path;
long size = getSize();
ResourceResponse resourceResponse = new ResourceResponse();
resourceResponse.setContentType(getMimeType());
resourceResponse.setAcceptRange(ContentRangeType.BYTES);
resourceResponse.setContentLength(size);
if (path.getFileName() != null) {
resourceResponse.setFileName(path.getFileName().toString());
}
RequestCycle cycle = RequestCycle.get();
Long startbyte = cycle.getMetaData(CONTENT_RANGE_STARTBYTE);
Long endbyte = cycle.getMetaData(CONTENT_RANGE_ENDBYTE);
resourceResponse.setWriteCallback(
new PartWriterCallback(getInputStream(), size, startbyte, endbyte));
return resourceResponse;
}
catch (IOException e)
{
throw new WicketRuntimeException(
"An error occurred while processing the media resource response", e);
}
}
/**
* Gets the size of the resource
*
* @return the size of the resource
* @throws IOException
* if the size attribute can't be read
*/
protected long getSize() throws IOException
{
return Files.readAttributes(path, BasicFileAttributes.class).size();
}
/**
* Gets the mime type to be used for the response it first uses the URL connection to get the
* mime type and after this the FileTypeDetector SPI is used.
*
* @return the mime type to be used for the response
* @throws IOException
* if the mime type couldn't be resolved
*/
protected String getMimeType() throws IOException
{
String mimeType = null;
if (Application.exists())
{
mimeType = Application.get().getMimeType(path.getFileName().toString());
}
if (mimeType == null)
{
mimeType = Files.probeContentType(path);
}
return mimeType;
}
/**
* Gets the input stream of the given path
*
* @return the input stream of the given path
* @throws IOException
* if there is an exception while receiving the input stream
*/
protected InputStream getInputStream() throws IOException
{
return Files.newInputStream(path);
}
}