hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/ophelpers/MultiComparator.java

/*
 * Copyright 2009-2010 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.hyracks.storage.am.common.ophelpers;

import java.io.ByteArrayInputStream;
import java.io.DataInput;
import java.io.DataInputStream;

import edu.uci.ics.hyracks.api.dataflow.value.IBinaryComparator;
import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
import edu.uci.ics.hyracks.api.dataflow.value.ITypeTrait;
import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
import edu.uci.ics.hyracks.dataflow.common.data.comparators.IntegerBinaryComparatorFactory;
import edu.uci.ics.hyracks.storage.am.common.api.IPrimitiveValueProvider;

public class MultiComparator {

	private static final long serialVersionUID = 1L;

	private IBinaryComparator[] cmps = null;
	private ITypeTrait[] typeTraits;
	private IPrimitiveValueProvider[] valueProviders = null;

	private IBinaryComparator intCmp = IntegerBinaryComparatorFactory.INSTANCE
			.createBinaryComparator();

	public IBinaryComparator getIntCmp() {
		return intCmp;
	}

	public MultiComparator(ITypeTrait[] typeTraits, IBinaryComparator[] cmps) {
		this.typeTraits = typeTraits;
		this.cmps = cmps;
	}

	public MultiComparator(ITypeTrait[] typeTraits, IBinaryComparator[] cmps,
			IPrimitiveValueProvider[] valueProviders) {
		this.typeTraits = typeTraits;
		this.cmps = cmps;
		this.valueProviders = valueProviders;
	}

	public int compare(ITupleReference tupleA, ITupleReference tupleB) {
		for (int i = 0; i < cmps.length; i++) {
			int cmp = cmps[i].compare(tupleA.getFieldData(i),
					tupleA.getFieldStart(i), tupleA.getFieldLength(i),
					tupleB.getFieldData(i), tupleB.getFieldStart(i),
					tupleB.getFieldLength(i));
			if (cmp < 0)
				return -1;
			else if (cmp > 0)
				return 1;
		}
		return 0;
	}

	public int fieldRangeCompare(ITupleReference tupleA,
			ITupleReference tupleB, int startFieldIndex, int numFields) {
		for (int i = startFieldIndex; i < startFieldIndex + numFields; i++) {
			int cmp = cmps[i].compare(tupleA.getFieldData(i),
					tupleA.getFieldStart(i), tupleA.getFieldLength(i),
					tupleB.getFieldData(i), tupleB.getFieldStart(i),
					tupleB.getFieldLength(i));
			if (cmp < 0)
				return -1;
			else if (cmp > 0)
				return 1;
		}
		return 0;
	}

	public String printTuple(ITupleReference tuple,
			ISerializerDeserializer[] fields) throws HyracksDataException {
		StringBuilder strBuilder = new StringBuilder();
		for (int i = 0; i < tuple.getFieldCount(); i++) {
			ByteArrayInputStream inStream = new ByteArrayInputStream(
					tuple.getFieldData(i), tuple.getFieldStart(i),
					tuple.getFieldLength(i));
			DataInput dataIn = new DataInputStream(inStream);
			Object o = fields[i].deserialize(dataIn);
			strBuilder.append(o.toString() + " ");
		}
		return strBuilder.toString();
	}

	public IBinaryComparator[] getComparators() {
		return cmps;
	}

	public int getKeyFieldCount() {
		return cmps.length;
	}

	public void setComparators(IBinaryComparator[] cmps) {
		this.cmps = cmps;
	}

	public int getFieldCount() {
		return typeTraits.length;
	}

	public ITypeTrait[] getTypeTraits() {
		return typeTraits;
	}

	public IPrimitiveValueProvider[] getValueProviders() {
		return valueProviders;
	}

}