/*
* 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.jdbc;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.teiid.client.util.ResultsFuture;
/**
* Handles the future processing logic and makes the appropriate calls to the callback
*/
public class NonBlockingRowProcessor implements
ResultsFuture.CompletionListener<Boolean> {
private static Logger logger = Logger.getLogger(NonBlockingRowProcessor.class.getName());
private StatementImpl stmt;
private StatementCallback callback;
public NonBlockingRowProcessor(StatementImpl stmt, StatementCallback callback) {
this.stmt = stmt;
this.callback = callback;
}
@Override
public void onCompletion(ResultsFuture<Boolean> future) {
try {
boolean hasResultSet = future.get();
if (!hasResultSet) {
callback.onComplete(stmt);
return;
}
final ResultSetImpl resultSet = stmt.getResultSet();
resultSet.asynch = true;
Runnable rowProcessor = new Runnable() {
@Override
public void run() {
while (true) {
try {
if (stmt.isClosed()) {
callback.onComplete(stmt);
break;
}
ResultsFuture<Boolean> hasNext = resultSet.submitNext();
synchronized (hasNext) {
if (!hasNext.isDone()) {
hasNext.addCompletionListener(new ResultsFuture.CompletionListener<Boolean>() {
@Override
public void onCompletion(
ResultsFuture<Boolean> f) {
if (processRow(f)) {
run();
}
}
});
break; // will be resumed by onCompletion above
}
}
if (!processRow(hasNext)) {
break;
}
} catch (Exception e) {
onException(e);
break;
}
}
}
};
rowProcessor.run();
} catch (Exception e) {
onException(e);
}
}
/**
* return true to continue processing
*/
boolean processRow(ResultsFuture<Boolean> hasNext) {
try {
if (!hasNext.get()) {
callback.onComplete(stmt);
return false;
}
List<?> row = stmt.getResultSet().getCurrentRecord();
if (row == null) {
if (callback instanceof ContinuousStatementCallback) {
((ContinuousStatementCallback)callback).beforeNextExecution(this.stmt);
}
return true;
}
callback.onRow(stmt, stmt.getResultSet());
return true;
} catch (Exception e) {
onException(e);
return false;
} catch (Throwable t) {
onException(new RuntimeException(t));
return false;
}
}
private void onException(Exception e) {
if (e instanceof ExecutionException) {
ExecutionException ee = (ExecutionException)e;
if (ee.getCause() instanceof Exception) {
e = (Exception) ee.getCause();
}
}
try {
callback.onException(stmt, e);
} catch (Exception e1) {
logger.log(Level.WARNING, "Unhandled exception from StatementCallback", e); //$NON-NLS-1$
}
}
}