/*
* JBoss, Home of Professional Open Source.
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA.
*/
package org.teiid.dqp.internal.process;
import java.io.IOException;
import java.nio.charset.Charset;
import java.sql.SQLException;
import javax.resource.spi.work.Work;
import org.teiid.client.lob.LobChunk;
import org.teiid.client.util.ResultsReceiver;
import org.teiid.core.TeiidComponentException;
import org.teiid.core.types.BlobType;
import org.teiid.core.types.ClobType;
import org.teiid.core.types.Streamable;
import org.teiid.core.types.XMLType;
import org.teiid.core.util.Assertion;
import org.teiid.core.util.ReaderInputStream;
import org.teiid.logging.LogManager;
import org.teiid.query.QueryPlugin;
public class LobWorkItem implements Work {
private RequestWorkItem parent;
private int chunkSize;
/* private work item state */
private String streamId;
private ByteLobChunkStream stream;
private int streamRequestId;
private ResultsReceiver<LobChunk> resultsReceiver;
public LobWorkItem(RequestWorkItem parent, DQPCore dqpCore, String streamId, int streamRequestId) {
this.chunkSize = dqpCore.getChunkSize();
this.streamId = streamId;
this.parent = parent;
this.streamRequestId = streamRequestId;
}
public void run() {
LobChunk chunk = null;
Exception ex = null;
boolean shouldClose = false;
try {
// If no previous stream is not found for this request create one and
// save for future
if (stream == null) {
stream = createLobStream(streamId);
}
// now get the chunk from stream
chunk = stream.getNextChunk();
shouldClose = chunk.isLast();
} catch (TeiidComponentException e) {
LogManager.logWarning(org.teiid.logging.LogConstants.CTX_DQP, e, QueryPlugin.Util.getString("ProcessWorker.LobError")); //$NON-NLS-1$
ex = e;
} catch (IOException e) {
ex = e;
}
synchronized (this) {
if (ex != null) {
resultsReceiver.exceptionOccurred(ex);
shouldClose = true;
} else {
resultsReceiver.receiveResults(chunk);
}
resultsReceiver = null;
}
if (shouldClose) {
close();
}
}
void close() {
try {
if (stream != null) {
stream.close();
}
} catch (IOException e) {
LogManager.logWarning(org.teiid.logging.LogConstants.CTX_DQP, e, QueryPlugin.Util.getString("ProcessWorker.LobError")); //$NON-NLS-1$
}
parent.removeLobStream(streamRequestId);
}
/**
* Create a object which can create a sequence of LobChunk objects on a given
* LOB object
*/
private ByteLobChunkStream createLobStream(String referenceStreamId)
throws TeiidComponentException, IOException {
// get the reference object in the buffer manager, and try to stream off
// the original sources.
Streamable<?> streamable = parent.resultsBuffer.getLobReference(referenceStreamId);
try {
if (streamable instanceof XMLType) {
XMLType xml = (XMLType)streamable;
return new ByteLobChunkStream(xml.getBinaryStream(), chunkSize);
}
else if (streamable instanceof ClobType) {
ClobType clob = (ClobType)streamable;
return new ByteLobChunkStream(new ReaderInputStream(clob.getCharacterStream(), Charset.forName(Streamable.ENCODING)), chunkSize);
}
BlobType blob = (BlobType)streamable;
return new ByteLobChunkStream(blob.getBinaryStream(), chunkSize);
} catch(SQLException e) {
throw new IOException(e);
}
}
synchronized void setResultsReceiver(ResultsReceiver<LobChunk> resultsReceiver) {
Assertion.isNull(this.resultsReceiver, "Cannot request results with a pending request"); //$NON-NLS-1$
this.resultsReceiver = resultsReceiver;
}
@Override
public void release() {
}
}