/*******************************************************************************
* Copyright (c) 2003, 2009 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.osgi.framework.internal.protocol.reference;
import java.io.*;
import java.net.URL;
import java.net.URLConnection;
import org.eclipse.osgi.framework.adaptor.FilePath;
import org.eclipse.osgi.framework.internal.core.FrameworkProperties;
import org.eclipse.osgi.framework.internal.core.ReferenceInputStream;
/**
* URLConnection for the reference protocol.
*/
public class ReferenceURLConnection extends URLConnection {
protected URL reference;
protected ReferenceURLConnection(URL url) {
super(url);
}
public synchronized void connect() throws IOException {
if (!connected) {
// TODO assumes that reference URLs are always based on file: URLs.
// There are not solid usecases to the contrary. Yet.
// Construct the ref URL carefully so as to preserve UNC paths etc.
String path = url.getPath().substring(5);
File file = new File(path);
URL ref;
if (!file.isAbsolute()) {
String installPath = getInstallPath();
if (installPath != null)
file = makeAbsolute(installPath, file);
}
// Pre-check if file exists, if not, and it contains escape characters,
// try decoding the absolute path generated by makeAbsolute
if (!file.exists() && path.indexOf('%') >= 0) {
String decodePath = FrameworkProperties.decode(file.getAbsolutePath());
File f = new File(decodePath);
if (f.exists())
file = f;
}
ref = file.toURL();
checkRead(file);
reference = ref;
}
}
private void checkRead(File file) throws IOException {
if (!file.exists())
throw new FileNotFoundException(file.toString());
if (file.isFile()) {
// Try to open the file to ensure that this is possible: see bug 260217
// If access is denied, a FileNotFoundException with (access denied) message is thrown
// Here file.canRead() cannot be used, because on Windows it does not
// return correct values - bug 6203387 in Sun's bug database
InputStream is = new FileInputStream(file);
is.close();
} else if (file.isDirectory()) {
// There is no straightforward way to check if a directory
// has read permissions - same issues for File.canRead() as above;
// try to list the files in the directory
File[] files = file.listFiles();
// File.listFiles() returns null if the directory does not exist
// (which is not the current case, because we check that it exists and is directory),
// or if an IO error occurred during the listing of the files, including if the
// access is denied
if (files == null)
throw new FileNotFoundException(file.toString() + " (probably access denied)"); //$NON-NLS-1$
} else {
// TODO not sure if we can get here.
}
}
public boolean getDoInput() {
return true;
}
public boolean getDoOutput() {
return false;
}
public InputStream getInputStream() throws IOException {
if (!connected) {
connect();
}
return new ReferenceInputStream(reference);
}
private String getInstallPath() {
String installURL = FrameworkProperties.getProperty("osgi.install.area"); //$NON-NLS-1$
if (installURL == null)
return null;
if (!installURL.startsWith("file:")) //$NON-NLS-1$
return null;
// this is the safest way to create a File object off a file: URL
return installURL.substring(5);
}
private static File makeAbsolute(String base, File relative) {
if (relative.isAbsolute())
return relative;
return new File(new FilePath(base + relative.getPath()).toString());
}
}