/*
* Copyright 2009-2013 by The Regents of the University of California
* 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 from
*
* 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 edu.uci.ics.pregelix.dataflow.std;
import java.io.DataOutput;
import java.nio.ByteBuffer;
import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
import edu.uci.ics.hyracks.api.context.IHyracksTaskContext;
import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider;
import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
import edu.uci.ics.hyracks.dataflow.common.comm.io.ArrayTupleBuilder;
import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAccessor;
import edu.uci.ics.hyracks.dataflow.common.comm.io.FrameTupleAppender;
import edu.uci.ics.hyracks.dataflow.common.comm.util.FrameUtils;
import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryInputUnaryOutputOperatorNodePushable;
import edu.uci.ics.hyracks.storage.am.btree.impls.RangePredicate;
import edu.uci.ics.hyracks.storage.am.common.api.IIndexAccessor;
import edu.uci.ics.hyracks.storage.am.common.api.IIndexCursor;
import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
import edu.uci.ics.hyracks.storage.am.common.dataflow.AbstractTreeIndexOperatorDescriptor;
import edu.uci.ics.hyracks.storage.am.common.dataflow.IndexDataflowHelper;
import edu.uci.ics.hyracks.storage.am.common.impls.NoOpOperationCallback;
import edu.uci.ics.hyracks.storage.am.common.ophelpers.MultiComparator;
import edu.uci.ics.hyracks.storage.am.common.tuples.PermutingFrameTupleReference;
public class IndexNestedLoopSetUnionOperatorNodePushable extends AbstractUnaryInputUnaryOutputOperatorNodePushable {
private IndexDataflowHelper treeIndexOpHelper;
private FrameTupleAccessor accessor;
private ByteBuffer writeBuffer;
private FrameTupleAppender appender;
private ArrayTupleBuilder tb;
private DataOutput dos;
private ITreeIndex index;
private RangePredicate rangePred;
private MultiComparator lowKeySearchCmp;
private IIndexCursor cursor;
protected IIndexAccessor indexAccessor;
private RecordDescriptor recDesc;
private final RecordDescriptor inputRecDesc;
private PermutingFrameTupleReference lowKey;
private PermutingFrameTupleReference highKey;
private ITupleReference currentTopTuple;
private boolean match;
public IndexNestedLoopSetUnionOperatorNodePushable(AbstractTreeIndexOperatorDescriptor opDesc,
IHyracksTaskContext ctx, int partition, IRecordDescriptorProvider recordDescProvider, boolean isForward,
int[] lowKeyFields, int[] highKeyFields) {
inputRecDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getActivityId(), 0);
treeIndexOpHelper = (IndexDataflowHelper) opDesc.getIndexDataflowHelperFactory().createIndexDataflowHelper(
opDesc, ctx, partition);
this.recDesc = recordDescProvider.getInputRecordDescriptor(opDesc.getActivityId(), 0);
if (lowKeyFields != null && lowKeyFields.length > 0) {
lowKey = new PermutingFrameTupleReference();
lowKey.setFieldPermutation(lowKeyFields);
}
if (highKeyFields != null && highKeyFields.length > 0) {
highKey = new PermutingFrameTupleReference();
highKey.setFieldPermutation(highKeyFields);
}
}
protected void setCursor() {
cursor = indexAccessor.createSearchCursor(false);
}
@Override
public void open() throws HyracksDataException {
accessor = new FrameTupleAccessor(treeIndexOpHelper.getTaskContext().getFrameSize(), recDesc);
try {
treeIndexOpHelper.open();
index = (ITreeIndex) treeIndexOpHelper.getIndexInstance();
writer.open();
rangePred = new RangePredicate(null, null, true, true, null, null);
int lowKeySearchFields = index.getComparatorFactories().length;
IBinaryComparator[] lowKeySearchComparators = new IBinaryComparator[lowKeySearchFields];
for (int i = 0; i < lowKeySearchFields; i++) {
lowKeySearchComparators[i] = index.getComparatorFactories()[i].createBinaryComparator();
}
lowKeySearchCmp = new MultiComparator(lowKeySearchComparators);
writeBuffer = treeIndexOpHelper.getTaskContext().allocateFrame();
tb = new ArrayTupleBuilder(index.getFieldCount());
dos = tb.getDataOutput();
appender = new FrameTupleAppender(treeIndexOpHelper.getTaskContext().getFrameSize());
appender.reset(writeBuffer, true);
indexAccessor = index.createAccessor(NoOpOperationCallback.INSTANCE, NoOpOperationCallback.INSTANCE);
setCursor();
/** set the search cursor */
rangePred.setLowKey(null, true);
rangePred.setHighKey(null, true);
cursor.reset();
indexAccessor.search(cursor, rangePred);
/** set up current top tuple */
if (cursor.hasNext()) {
cursor.next();
currentTopTuple = cursor.getTuple();
match = false;
}
} catch (Exception e) {
closeResource();
throw new HyracksDataException(e);
}
}
@Override
public void nextFrame(ByteBuffer buffer) throws HyracksDataException {
accessor.reset(buffer);
int tupleCount = accessor.getTupleCount();
try {
for (int i = 0; i < tupleCount;) {
if (lowKey != null)
lowKey.reset(accessor, i);
if (highKey != null)
highKey.reset(accessor, i);
// TODO: currently use low key only, check what they mean
if (currentTopTuple != null) {
int cmp = compare(lowKey, currentTopTuple);
if (cmp == 0) {
outputMatch(i);
i++;
} else if ((cmp > 0)) {
moveTreeCursor();
} else {
writeLeftResults(accessor, i);
i++;
}
} else {
writeLeftResults(accessor, i);
i++;
}
}
} catch (Exception e) {
closeResource();
throw new HyracksDataException(e);
}
}
private void outputMatch(int i) throws Exception {
writeLeftResults(accessor, i);
match = true;
}
private void moveTreeCursor() throws Exception {
if (!match) {
writeRightResults(currentTopTuple);
}
if (cursor.hasNext()) {
cursor.next();
currentTopTuple = cursor.getTuple();
match = false;
} else {
currentTopTuple = null;
}
}
@Override
public void close() throws HyracksDataException {
try {
while (currentTopTuple != null) {
moveTreeCursor();
}
if (appender.getTupleCount() > 0) {
FrameUtils.flushFrame(writeBuffer, writer);
}
try {
cursor.close();
} catch (Exception e) {
throw new HyracksDataException(e);
}
} catch (Exception e) {
closeResource();
throw new HyracksDataException(e);
} finally{
treeIndexOpHelper.close();
writer.close();
}
}
@Override
public void fail() throws HyracksDataException {
closeResource();
populateFailure();
}
private void closeResource() throws HyracksDataException {
try {
cursor.close();
} catch (Exception e) {
throw new HyracksDataException(e);
} finally {
treeIndexOpHelper.close();
}
}
private void populateFailure() throws HyracksDataException {
writer.fail();
}
/** compare tuples */
private int compare(ITupleReference left, ITupleReference right) throws Exception {
return lowKeySearchCmp.compare(left, right);
}
/** write the right result */
private void writeRightResults(ITupleReference frameTuple) throws Exception {
tb.reset();
for (int i = 0; i < frameTuple.getFieldCount(); i++) {
dos.write(frameTuple.getFieldData(i), frameTuple.getFieldStart(i), frameTuple.getFieldLength(i));
tb.addFieldEndOffset();
}
if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
FrameUtils.flushFrame(writeBuffer, writer);
appender.reset(writeBuffer, true);
if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
throw new IllegalStateException();
}
}
}
/** write the left result */
private void writeLeftResults(IFrameTupleAccessor leftAccessor, int tIndex) throws Exception {
tb.reset();
for (int i = 0; i < inputRecDesc.getFields().length; i++) {
int tupleStart = leftAccessor.getTupleStartOffset(tIndex);
int fieldStart = leftAccessor.getFieldStartOffset(tIndex, i);
int offset = leftAccessor.getFieldSlotsLength() + tupleStart + fieldStart;
int len = leftAccessor.getFieldEndOffset(tIndex, i) - fieldStart;
dos.write(leftAccessor.getBuffer().array(), offset, len);
tb.addFieldEndOffset();
}
if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
FrameUtils.flushFrame(writeBuffer, writer);
appender.reset(writeBuffer, true);
if (!appender.append(tb.getFieldEndOffsets(), tb.getByteArray(), 0, tb.getSize())) {
throw new IllegalStateException();
}
}
}
}