/* $HeadURL:: $
* $Id$
*
* Copyright (c) 2009-2010 DuraSpace
* http://duraspace.org
*
* In collaboration with Topaz Inc.
* http://www.topazproject.org
*
* 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.akubraproject.impl;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Map;
import org.akubraproject.Blob;
import org.akubraproject.BlobStore;
import org.akubraproject.BlobStoreConnection;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* An abstract base class for blob store connections.
*
* @author Pradeep Krishnan
*/
public abstract class AbstractBlobStoreConnection implements BlobStoreConnection {
private static final Logger log = LoggerFactory.getLogger(AbstractBlobStoreConnection.class);
protected final BlobStore owner;
protected final StreamManager streamManager;
protected boolean closed = false;
protected AbstractBlobStoreConnection(BlobStore owner) {
this(owner, null);
}
protected AbstractBlobStoreConnection(BlobStore owner, StreamManager streamManager) {
this.owner = owner;
this.streamManager = streamManager;
}
@Override
public BlobStore getBlobStore() {
return owner;
}
@Override
public Blob getBlob(InputStream content, long estimatedSize, Map<String, String> hints)
throws IOException, UnsupportedOperationException {
Blob blob = getBlob(null, hints);
boolean success = false;
try {
OutputStream out = blob.openOutputStream(estimatedSize, true);
try {
IOUtils.copyLarge(content, out);
out.close();
out = null;
} finally {
if (out != null)
IOUtils.closeQuietly(out);
}
success = true;
} finally {
if (!success) {
try {
blob.delete();
} catch (Throwable t) {
log.error("Error deleting blob after blob-creation failure", t);
}
}
}
return blob;
}
@Override
public void close() {
if (!closed) {
closed = true;
if (streamManager != null)
streamManager.connectionClosed(this);
}
}
@Override
public boolean isClosed() {
return closed;
}
/**
* Helper that checks whether the connection is open and throws an exception if not.
*
* @throws IllegalStateException if the connection has been closed
*/
protected void ensureOpen() throws IllegalStateException {
if (isClosed())
throw new IllegalStateException("Connection closed.");
}
}