rrddef.java

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

	 * @param consolFun Consolidation function. Valid values are "AVERAGE",
	 *                  "MIN", "MAX" and "LAST" (these constants are conveniently defined in the
	 *                  {@link ConsolFuns} class)
	 * @param xff	   X-files factor. Valid values are between 0 and 1.
	 * @param steps	 Number of archive steps
	 * @param rows	  Number of archive rows
	 * @throws RrdException Thrown if archive with the same consolidation function
	 *                      and the same number of steps is already added.
	 */
	public void addArchive(String consolFun, double xff, int steps, int rows)
			throws RrdException {
		addArchive(new ArcDef(consolFun, xff, steps, rows));
	}

	/**
	 * Adds single archive to RRD definition from a RRDTool-like
	 * archive definition string. The string must have five elements separated with colons
	 * (:) in the following order:<p>
	 * <pre>
	 * RRA:consolidationFunction:XFilesFactor:steps:rows
	 * </pre>
	 * For example:</p>
	 * <pre>
	 * RRA:AVERAGE:0.5:10:1000
	 * </pre>
	 * For more information on archive definition parameters see <code>rrdcreate</code>
	 * man page.<p>
	 *
	 * @param rrdToolArcDef Archive definition string with the syntax borrowed from RRDTool.
	 * @throws RrdException Thrown if invalid string is supplied.
	 */
	public void addArchive(String rrdToolArcDef) throws RrdException {
		RrdException rrdException = new RrdException(
				"Wrong rrdtool-like archive definition: " + rrdToolArcDef);
		StringTokenizer tokenizer = new StringTokenizer(rrdToolArcDef, ":");
		if (tokenizer.countTokens() != 5) {
			throw rrdException;
		}
		String[] tokens = new String[5];
		for (int curTok = 0; tokenizer.hasMoreTokens(); curTok++) {
			tokens[curTok] = tokenizer.nextToken();
		}
		if (!tokens[0].equalsIgnoreCase("RRA")) {
			throw rrdException;
		}
		String consolFun = tokens[1];
		double xff;
		try {
			xff = Double.parseDouble(tokens[2]);
		}
		catch (NumberFormatException nfe) {
			throw rrdException;
		}
		int steps;
		try {
			steps = Integer.parseInt(tokens[3]);
		}
		catch (NumberFormatException nfe) {
			throw rrdException;
		}
		int rows;
		try {
			rows = Integer.parseInt(tokens[4]);
		}
		catch (NumberFormatException nfe) {
			throw rrdException;
		}
		addArchive(new ArcDef(consolFun, xff, steps, rows));
	}

	void validate() throws RrdException {
		if (dsDefs.size() == 0) {
			throw new RrdException("No RRD datasource specified. At least one is needed.");
		}
		if (arcDefs.size() == 0) {
			throw new RrdException("No RRD archive specified. At least one is needed.");
		}
	}

	/**
	 * Returns all data source definition objects specified so far.
	 *
	 * @return Array of data source definition objects
	 */
	public DsDef[] getDsDefs() {
		return dsDefs.toArray(new DsDef[0]);
	}

	/**
	 * Returns all archive definition objects specified so far.
	 *
	 * @return Array of archive definition objects.
	 */
	public ArcDef[] getArcDefs() {
		return arcDefs.toArray(new ArcDef[0]);
	}

	/**
	 * Returns number of defined datasources.
	 *
	 * @return Number of defined datasources.
	 */
	public int getDsCount() {
		return dsDefs.size();
	}

	/**
	 * Returns number of defined archives.
	 *
	 * @return Number of defined archives.
	 */
	public int getArcCount() {
		return arcDefs.size();
	}

	/**
	 * Returns string that represents all specified RRD creation parameters. Returned string
	 * has the syntax of RRDTool's <code>create</code> command.
	 *
	 * @return Dumped content of <code>RrdDb</code> object.
	 */
	public String dump() {
		StringBuffer buffer = new StringBuffer("create \"");
		buffer.append(path).append("\"");
		buffer.append(" --start ").append(getStartTime());
		buffer.append(" --step ").append(getStep()).append(" ");
		for (DsDef dsDef : dsDefs) {
			buffer.append(dsDef.dump()).append(" ");
		}
		for (ArcDef arcDef : arcDefs) {
			buffer.append(arcDef.dump()).append(" ");
		}
		return buffer.toString().trim();
	}

	String getRrdToolCommand() {
		return dump();
	}

	void removeDatasource(String dsName) throws RrdException {
		for (int i = 0; i < dsDefs.size(); i++) {
			DsDef dsDef = dsDefs.get(i);
			if (dsDef.getDsName().equals(dsName)) {
				dsDefs.remove(i);
				return;
			}
		}
		throw new RrdException("Could not find datasource named '" + dsName + "'");
	}

	void saveSingleDatasource(String dsName) {
		Iterator<DsDef> it = dsDefs.iterator();
		while (it.hasNext()) {
			DsDef dsDef = it.next();
			if (!dsDef.getDsName().equals(dsName)) {
				it.remove();
			}
		}
	}

	void removeArchive(String consolFun, int steps) throws RrdException {
		ArcDef arcDef = findArchive(consolFun, steps);
		if (!arcDefs.remove(arcDef)) {
			throw new RrdException("Could not remove archive " + consolFun + "/" + steps);
		}
	}

	ArcDef findArchive(String consolFun, int steps) throws RrdException {
		for (ArcDef arcDef : arcDefs) {
			if (arcDef.getConsolFun().equals(consolFun) && arcDef.getSteps() == steps) {
				return arcDef;
			}
		}
		throw new RrdException("Could not find archive " + consolFun + "/" + steps);
	}

	/**
	 * Exports RrdDef object to output stream in XML format. Generated XML code can be parsed
	 * with {@link RrdDefTemplate} class.
	 *
	 * @param out Output stream
	 */
	public void exportXmlTemplate(OutputStream out) {
		XmlWriter xml = new XmlWriter(out);
		xml.startTag("rrd_def");
		xml.writeTag("path", getPath());
		xml.writeTag("step", getStep());
		xml.writeTag("start", getStartTime());
		// datasources
		DsDef[] dsDefs = getDsDefs();
		for (DsDef dsDef : dsDefs) {
			xml.startTag("datasource");
			xml.writeTag("name", dsDef.getDsName());
			xml.writeTag("type", dsDef.getDsType());
			xml.writeTag("heartbeat", dsDef.getHeartbeat());
			xml.writeTag("min", dsDef.getMinValue(), "U");
			xml.writeTag("max", dsDef.getMaxValue(), "U");
			xml.closeTag(); // datasource
		}
		ArcDef[] arcDefs = getArcDefs();
		for (ArcDef arcDef : arcDefs) {
			xml.startTag("archive");
			xml.writeTag("cf", arcDef.getConsolFun());
			xml.writeTag("xff", arcDef.getXff());
			xml.writeTag("steps", arcDef.getSteps());
			xml.writeTag("rows", arcDef.getRows());
			xml.closeTag(); // archive
		}
		xml.closeTag(); // rrd_def
		xml.flush();
	}

	/**
	 * Exports RrdDef object to string in XML format. Generated XML string can be parsed
	 * with {@link RrdDefTemplate} class.
	 *
	 * @return XML formatted string representing this RrdDef object
	 */
	public String exportXmlTemplate() {
		ByteArrayOutputStream out = new ByteArrayOutputStream();
		exportXmlTemplate(out);
		return out.toString();
	}

	/**
	 * Exports RrdDef object to a file in XML format. Generated XML code can be parsed
	 * with {@link RrdDefTemplate} class.
	 *
	 * @param filePath Path to the file
	 */
	public void exportXmlTemplate(String filePath) throws IOException {
		FileOutputStream out = new FileOutputStream(filePath, false);
		exportXmlTemplate(out);
		out.close();
	}

	/**
	 * Returns the number of storage bytes required to create RRD from this
	 * RrdDef object.
	 *
	 * @return Estimated byte count of the underlying RRD storage.
	 */
	public long getEstimatedSize() {
		int dsCount = dsDefs.size();
		int arcCount = arcDefs.size();
		int rowsCount = 0;
		for (ArcDef arcDef : arcDefs) {
			rowsCount += arcDef.getRows();
		}
		return calculateSize(dsCount, arcCount, rowsCount);
	}

	static long calculateSize(int dsCount, int arcCount, int rowsCount) {
		// return 64L + 128L * dsCount + 56L * arcCount +
		//	20L * dsCount * arcCount + 8L * dsCount * rowsCount;
		return (24L + 48L * dsCount + 16L * arcCount +
				20L * dsCount * arcCount + 8L * dsCount * rowsCount) +
				(1L + 2L * dsCount + arcCount) * 2L * RrdPrimitive.STRING_LENGTH;
	}

	/**
	 * Compares the current RrdDef with another. RrdDefs are considered equal if:<p>
	 * <ul>
	 * <li>RRD steps match
	 * <li>all datasources have exactly the same definition in both RrdDef objects (datasource names,
	 * types, heartbeat, min and max values must match)
	 * <li>all archives have exactly the same definition in both RrdDef objects (archive consolidation
	 * functions, X-file factors, step and row counts must match)
	 * </ul>
	 *
	 * @param obj The second RrdDef object
	 * @return true if RrdDefs match exactly, false otherwise
	 */
	public boolean equals(Object obj) {
		if (obj == null || !(obj instanceof RrdDef)) {
			return false;
		}
		RrdDef rrdDef2 = (RrdDef) obj;
		// check primary RRD step
		if (step != rrdDef2.step) {
			return false;
		}
		// check datasources
		DsDef[] dsDefs = getDsDefs(), dsDefs2 = rrdDef2.getDsDefs();
		if (dsDefs.length != dsDefs2.length) {
			return false;
		}
		for (DsDef dsDef : dsDefs) {
			boolean matched = false;
			for (DsDef dsDef2 : dsDefs2) {
				if (dsDef.exactlyEqual(dsDef2)) {
					matched = true;
					break;
				}
			}
			// this datasource could not be matched
			if (!matched) {
				return false;
			}
		}
		// check archives
		ArcDef[] arcDefs = getArcDefs(), arcDefs2 = rrdDef2.getArcDefs();
		if (arcDefs.length != arcDefs2.length) {
			return false;
		}
		for (ArcDef arcDef : arcDefs) {
			boolean matched = false;
			for (ArcDef arcDef2 : arcDefs2) {
				if (arcDef.exactlyEqual(arcDef2)) {
					matched = true;
					break;
				}
			}
			// this archive could not be matched
			if (!matched) {
				return false;
			}
		}
		// everything matches
		return true;
	}

	/**
	 * Removes all datasource definitions.
	 */
	public void removeDatasources() {
		dsDefs.clear();
	}

	/**
	 * Removes all RRA archive definitions.
	 */
	public void removeArchives() {
		arcDefs.clear();
	}
}