cdpstatusblock.java

jrobin,使用纯java实现的RRD数据库,使用RRD数据库来统计数据.

/*
 * Copyright (C) 2001 Ciaran Treanor <[e-mail]>
 *
 * Distributable under GPL license.
 * See terms of license at gnu.org.
 *
 * $Id: CDPStatusBlock.java,v 1.1 2006/04/25 08:09:28 sasam Exp $
 */
package org.jrobin.core.jrrd;

import java.io.IOException;
import java.io.PrintStream;

/**
 * Instances of this class model the consolidation data point status from an RRD file.
 *
 * @author <a href="mailto:[e-mail]">Ciaran Treanor</a>
 * @version $Revision: 1.1 $
 */
public class CDPStatusBlock {

	long offset;
	long size;
	int unknownDatapoints;
	double value;

	CDPStatusBlock(RRDFile file) throws IOException {

		offset = file.getFilePointer();
		value = file.readDouble();
		unknownDatapoints = file.readInt();

		// Skip rest of cdp_prep_t.scratch
		file.skipBytes(68);

		size = file.getFilePointer() - offset;
	}

	/**
	 * Returns the number of unknown primary data points that were integrated.
	 *
	 * @return the number of unknown primary data points that were integrated.
	 */
	public int getUnknownDatapoints() {
		return unknownDatapoints;
	}

	/**
	 * Returns the value of this consolidated data point.
	 *
	 * @return the value of this consolidated data point.
	 */
	public double getValue() {
		return value;
	}

	void toXml(PrintStream s) {

		s.print("\t\t\t<ds><value> ");
		s.print(value);
		s.print(" </value>  <unknown_datapoints> ");
		s.print(unknownDatapoints);
		s.println(" </unknown_datapoints></ds>");
	}

	/**
	 * Returns a summary the contents of this CDP status block.
	 *
	 * @return a summary of the information contained in the CDP status block.
	 */
	public String toString() {

		StringBuffer sb = new StringBuffer("[CDPStatusBlock: OFFSET=0x");

		sb.append(Long.toHexString(offset));
		sb.append(", SIZE=0x");
		sb.append(Long.toHexString(size));
		sb.append(", unknownDatapoints=");
		sb.append(unknownDatapoints);
		sb.append(", value=");
		sb.append(value);
		sb.append("]");

		return sb.toString();
	}
}