de.schlichtherle.io.archive.spi.TransientIOException Maven / Gradle / Ivy
/*
* Copyright (C) 2006-2010 Schlichtherle IT Services
*
* 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 de.schlichtherle.io.archive.spi;
import de.schlichtherle.io.File;
import java.io.IOException;
/**
* May be thrown by archive drivers to indicate that an {@link IOException}
* occured as a transient event when accessing an archive file and another
* try to access the same archive file may finally succeed.
* On the other hand, if the archive controller catches an IOException from
* an an archive driver when trying to access an archive file which is
* not a {@code TransientIOException}, then the archive
* controller may consider the archive file to be a false positive and cache
* the exception until {@link File#umount} or {@link File#update} is called.
*
* This feature is primarily used by the RAES encrypted ZIP file driver
* family when prompting for passwords has been cancelled by the user.
* In this case, the driver will wrap the {@code IOException} in a
* {@code TransientIOException} and throw this instead to signal that
* another attempt to prompt the user should be allowed.
*
* This class is marked final since the archive controller will throw
* away this exception anyway and deal with the transient cause only.
*
* @author Christian Schlichtherle
* @version $Id: TransientIOException.java 06f3ba684701 2010/11/04 01:15:55 christian $
* @since TrueZIP 6.4
*/
public final class TransientIOException extends IOException {
/**
* @param cause The transient cause of this exception.
* @throws NullPointerException If {@code cause} is {@code null}.
*/
public TransientIOException(IOException cause) {
if (cause == null)
throw new NullPointerException();
super.initCause(cause);
}
/**
* Returns the transient cause of this exception as an
* {@code IOException} - {@code null} is never returned.
*/
public IOException getTransientCause() {
return (IOException) getCause();
}
}