hyracks/hyracks-dataflow-common/src/main/java/edu/uci/ics/hyracks/dataflow/common/comm/util/FrameUtils.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.dataflow.common.comm.util;

import java.nio.ByteBuffer;

import edu.uci.ics.hyracks.api.comm.IFrameTupleAccessor;
import edu.uci.ics.hyracks.api.comm.IFrameWriter;
import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;

public class FrameUtils {
    public static void copy(ByteBuffer srcFrame, ByteBuffer destFrame) {
        makeReadable(srcFrame);
        destFrame.clear();
        destFrame.put(srcFrame);
    }

    public static void makeReadable(ByteBuffer frame) {
        frame.position(0);
        frame.limit(frame.capacity());
    }

    public static void flushFrame(ByteBuffer buffer, IFrameWriter writer) throws HyracksDataException {
        buffer.position(0);
        buffer.limit(buffer.capacity());
        writer.nextFrame(buffer);
        buffer.position(0);
        buffer.limit(buffer.capacity());
    }

    public static int getAbsoluteFieldStartOffset(IFrameTupleAccessor accessor, int tuple, int field) {
        return accessor.getTupleStartOffset(tuple) + accessor.getFieldSlotsLength()
                + accessor.getFieldStartOffset(tuple, field);
    }
}