/*
* Copyright 2002-2005 The Apache Software Foundation.
*
* 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.apache.commons.vfs.provider.url;
import org.apache.commons.httpclient.URIException;
import org.apache.commons.vfs.FileName;
import org.apache.commons.vfs.FileObject;
import org.apache.commons.vfs.FileSystemException;
import org.apache.commons.vfs.FileType;
import org.apache.commons.vfs.provider.AbstractFileObject;
import org.apache.commons.vfs.provider.URLFileName;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
/**
* A {@link FileObject} implementation backed by a {@link URL}.
*
* @author <a href="mailto:adammurdoch@apache.org">Adam Murdoch</a>
* @todo Implement set lastModified and get/set attribute
* @todo Implement getOutputStream()
*/
public class UrlFileObject
extends AbstractFileObject
implements FileObject
{
private URL url;
protected UrlFileObject(final UrlFileSystem fs,
final FileName fileName)
{
super(fileName, fs);
}
/**
* Attaches this file object to its file resource. This method is called
* before any of the doBlah() or onBlah() methods. Sub-classes can use
* this method to perform lazy initialisation.
*/
protected void doAttach() throws Exception
{
if (url == null)
{
// url = new URL(getName().getURI());
url = createURL(getName());
}
}
protected URL createURL(final FileName name) throws MalformedURLException, FileSystemException, URIException
{
if (name instanceof URLFileName)
{
URLFileName urlName = (URLFileName) getName();
// TODO: charset
return new URL(urlName.getURIEncoded(null));
}
return new URL(getName().getURI());
}
/**
* Determines the type of the file.
*/
protected FileType doGetType() throws Exception
{
try
{
// Attempt to connect & check status
final URLConnection conn = url.openConnection();
final InputStream in = conn.getInputStream();
try
{
if (conn instanceof HttpURLConnection)
{
final int status = ((HttpURLConnection) conn).getResponseCode();
// 200 is good, maybe add more later...
if (HttpURLConnection.HTTP_OK != status)
{
return FileType.IMAGINARY;
}
}
return FileType.FILE;
}
finally
{
in.close();
}
}
catch (final FileNotFoundException e)
{
return FileType.IMAGINARY;
}
}
/**
* Returns the size of the file content (in bytes).
*/
protected long doGetContentSize() throws Exception
{
final URLConnection conn = url.openConnection();
final InputStream in = conn.getInputStream();
try
{
return conn.getContentLength();
}
finally
{
in.close();
}
}
/**
* Returns the last modified time of this file.
*/
protected long doGetLastModifiedTime()
throws Exception
{
final URLConnection conn = url.openConnection();
final InputStream in = conn.getInputStream();
try
{
return conn.getLastModified();
}
finally
{
in.close();
}
}
/**
* Lists the children of the file.
*/
protected String[] doListChildren() throws Exception
{
throw new FileSystemException("Not implemented.");
}
/**
* Creates an input stream to read the file content from.
*/
protected InputStream doGetInputStream() throws Exception
{
return url.openStream();
}
}