/*
* 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 com.facebook.presto.tuple;
import com.facebook.presto.tuple.TupleInfo.Type;
import io.airlift.slice.Slice;
import it.unimi.dsi.fastutil.ints.AbstractIntComparator;
import java.util.List;
import static com.google.common.base.Preconditions.checkArgument;
/**
* Compares two field-aligned Tuple within a slice field by field.
* Ordering preference is given to fields at lower indicies.
*/
public class DirectFieldOrderedTupleComparator
extends AbstractIntComparator
{
private final TupleInfo tupleInfo;
private final Slice slice;
private final Type[] types;
public DirectFieldOrderedTupleComparator(TupleInfo tupleInfo, Slice slice)
{
this.tupleInfo = tupleInfo;
this.slice = slice;
List<Type> types = tupleInfo.getTypes();
this.types = types.toArray(new Type[types.size()]);
}
@Override
public int compare(int left, int right)
{
checkArgument(left >= 0 && right >= 0);
for (int field = 0; field < types.length; field++) {
Type type = types[field];
int comparison;
switch (type) {
case BOOLEAN:
comparison = Boolean.compare(tupleInfo.getBoolean(slice, left, field), tupleInfo.getBoolean(slice, right, field));
break;
case FIXED_INT_64:
comparison = Long.compare(tupleInfo.getLong(slice, left, field), tupleInfo.getLong(slice, right, field));
break;
case DOUBLE:
comparison = Double.compare(tupleInfo.getDouble(slice, left, field), tupleInfo.getDouble(slice, right, field));
break;
case VARIABLE_BINARY:
comparison = tupleInfo.getSlice(slice, left, field).compareTo(tupleInfo.getSlice(slice, right, field));
break;
default:
throw new AssertionError("unimplemented type: " + type);
}
if (comparison != 0) {
return comparison;
}
}
return 0;
}
}