intreader.java

来自「tinyos最新版」· Java 代码 · 共 75 行

// $Id: IntReader.java,v 1.7 2003/10/07 21:46:07 idgay Exp $

/*									tab:4
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 * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
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 * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
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 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
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 * Copyright (c) 2002-2003 Intel Corporation
 * All rights reserved.
 *
 * This file is distributed under the terms in the attached INTEL-LICENSE     
 * file. If you do not find these files, copies can be found by writing to
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package net.tinyos.tinydb;

import net.tinyos.tinydb.*;
import net.tinyos.util.ByteOps;

/**
 * Implements reader for aggregates whose state is determined by just one
 * integer - such as MIN, MAX, SUM
 *
 * @author Eugene Shvets
 * @version 1.0, October 23, 2002
 *
 * Changed 11.3.2002 to use objects for state.  SRM.
 */
public class IntReader implements net.tinyos.tinydb.AggregateResultsReader {
    
    /**
	 * Reads data from the byte array from QueryResultMessage
	 */
    public void read(byte[] data) {
		myState = ByteOps.makeInt(data[0], data[1]);
    }
    
    /**
	 * Calculates final value of the aggregate.
	 */
    public void finalizeValue() {
		// dont need to do anything
    }
    
    /**
	 * Returns string representation of the finalized value
	 */
    public String getValue() {
		return Integer.toString(myState);
    }
	
	public void copyResultState(AggregateResultsReader reader) {
		if (! (reader instanceof IntReader)) throw new IllegalArgumentException("Wrong type reader");
		((IntReader)reader).myState = myState;
	}
	
	int myState;
}