简单封装JRobin1.4

	// datasource类型	private static final String DS_TYPE = "GAUGE";

	// 默认从多个数据中取综合值的方式
	private static final ConsolFun DEFAULT_CONSOL_FUN = ConsolFun.MAX;

	// 默认曲线形状
	private static final ChartSeries DEFAULT_CHART_SERIES = ChartSeries.LINE;

	// 默认图片格式
	private static final GraphFormat DEFAULT_GRAPH_FORMAT = GraphFormat.PNG;

	// 默认顺序颜色
	private static final Color[] colors = new Color[] { Color.GREEN,
			Color.BLUE, Color.CYAN, Color.ORANGE, Color.PINK, Color.MAGENTA,
			Color.GRAY, Color.DARK_GRAY };
	

	/**
	 * 向RRD文件，插入数据
	 * 
	 * @param rrdPath
	 *            RRD文件路径
	 * @param dsNames dsName数组，类似于数据表的栏位概念
	 * @param values
	 * @param collectTimeUnitsSecond
	 *            数据所在时间，以秒为单位
	 * @throws RrdException
	 * @throws IOException
	 */
	public static void insertRrdData(String rrdPath, String[] dsNames,
			double[] values, long collectTimeUnitsSecond) throws RrdException,
			IOException {
		if (dsNames != null && dsNames.length > 0) {
			// 取得RRD数据库连接池
			RrdDbPool rrdPool = RrdDbPool.getInstance();

			// 取得rrd数据库文件
			RrdDb rrdDb = rrdPool.requestRrdDb(rrdPath);

			// 创建rrd记录
			Sample sample = rrdDb.createSample(collectTimeUnitsSecond);
			for (int i = 0; i < values.length; i++) {
				sample.setValue(dsNames[i], values[i]);
			}
			// update database
			sample.update();
			// release RRD database reference
			rrdPool.release(rrdDb);
		}
	}

	/**
	 * 重新创建RRD文件
	 * @param rrdPath RRD文件路径
	 * @param dsNames dsName数组，类似于数据表的栏位概念
	 * @param archiveModels 
	 * @param startTime 插入的数据不能早于这个时间,为0时，将默认使用当前时间
	 * @param rrdStep RRD文件接收数据的频率，即多少秒接收一次数据
	 * @throws RrdException
	 * @throws IOException
	 */
	public static void createRrdFile(String rrdPath, String[] dsNames,
			Collection<JRobinArchiveModel> archiveModels, long startTime,
			long rrdStep) throws RrdException, IOException {		
		RrdDef rrdDef = null;

		long step = rrdStep;

		// create RRD file since it does not exist
		if (step > 0) {
			if (startTime > 0) {
				rrdDef = new RrdDef(rrdPath, startTime - 1, step);
			} else {
				rrdDef = new RrdDef(rrdPath, startTime - 1);
			}
		} else {
			rrdDef = new RrdDef(rrdPath);
		}

		// (String dsName, String dsType, long heartbeat,double minValue,
		// double maxValue)
		for (int i = 0; i < dsNames.length; i++) {
			rrdDef.addDatasource(dsNames[i], DS_TYPE, 600, Double.NaN,
					Double.NaN);
		}

		for (Iterator<JRobinArchiveModel> iterator = archiveModels.iterator(); iterator
				.hasNext();) {
			JRobinArchiveModel robinArchiveModel = iterator.next();
			ConsolFun consolFun = robinArchiveModel.getConsolFun();
			if (consolFun == null) {
				consolFun = DEFAULT_CONSOL_FUN;
			}
			rrdDef.addArchive(consolFun.toString(), 0.5, robinArchiveModel
					.getSteps(), robinArchiveModel.getRows());
		}

		// create RRD file in the pool
		RrdDbPool rrdPool = RrdDbPool.getInstance();
		RrdDb rrdDb = rrdPool.requestRrdDb(rrdDef);
		
		rrdPool.release(rrdDb);
	}
	

	/**
	 * 返回生成图片的字节码，而不写入文件
	 * @param chartModels 一组曲线定义对象
	 * @param graphingParam 绘图的基本参数
	 * @return
	 * @throws RrdException
	 * @throws IOException
	 */
	public static byte[] graphBytes(Collection<JRobinChartModel> chartModels,
			JRobinGraphingParam graphingParam) throws RrdException, IOException {
		byte[] bytes = null;

		RrdGraph rrdGraph = constructionRrdGraph(chartModels, graphingParam);

		// 取得图形的字节码
		if (!graphingParam.isUseCustomGraphSizeFlag()) {
			bytes = byteGraph(rrdGraph, graphingParam.getGraphFormat());
		} else {
			bytes = byteGraph(rrdGraph, graphingParam.getGraphFormat(),
					graphingParam.getWidth(), graphingParam.getHeight(),
					graphingParam.getQuality());
		}
		return bytes;
	}

	/**
	 * 返回生成图片输出到指定文件(文件位置由JRobinGraphingParam对象的grapfilePath指定）
	 * @param chartModels 一组曲线定义对象
	 * @param graphingParam 绘图的基本参数
	 * @throws RrdException
	 * @throws IOException
	 */
	public static void graphing(Collection<JRobinChartModel> chartModels,
			JRobinGraphingParam graphingParam)
			throws RrdException, IOException {

		RrdGraph rrdGraph = constructionRrdGraph(chartModels, graphingParam);
		// 保存图形到文件
		if (!graphingParam.isUseCustomGraphSizeFlag()) {
			saveGraph(rrdGraph, graphingParam.getGraphFormat(), graphingParam.getGrapfilePath());
		} else {
			saveGraph(rrdGraph, graphingParam.getGraphFormat(), graphingParam
					.getWidth(), graphingParam.getHeight(), graphingParam
					.getQuality(), graphingParam.getGrapfilePath());
		}
	}

	/**
	 * 构建RrdGraph图形对象
	 * @param chartModels
	 * @param graphingParam
	 * @return
	 * @throws RrdException
	 */
	private static RrdGraph constructionRrdGraph(
			Collection<JRobinChartModel> chartModels,
			JRobinGraphingParam graphingParam) throws RrdException {
		// 图形
		RrdGraph rrdGraph = null;
		String defaultRrdPath = graphingParam.getRrdPath();

		int legendColumns = graphingParam.getLegendColumns();
		if (legendColumns == 0) {
			legendColumns = 1;
		}

		// 图形定义
		RrdGraphDef graphDef = new RrdGraphDef();

		// 指定数据的时间跨度
		graphDef.setTimePeriod(graphingParam.getStartTime(), graphingParam
				.getEndTime());

		// 不显示JRobin的签名
		graphDef.setShowSignature(false);
		// 中文字体
		graphDef.setDefaultFont(new Font("Monospaced", Font.PLAIN, 11));
		graphDef.setTitleFont(new Font("SansSerif", Font.BOLD, 14));

		// 标题
		if (graphingParam.getTitle() != null) {
			graphDef.setTitle(graphingParam.getTitle());
		}

		// 指定Y轴取值范围
		if (graphingParam.isUseCustomGridYRangeFlag()) {
			graphDef.setGridRange(graphingParam.getGridYLower(), graphingParam
					.getGridYUpper(), true);
		}

		int i = 0;
		for (Iterator<JRobinChartModel> iterator = chartModels.iterator(); iterator
				.hasNext(); i++) {
			JRobinChartModel robinChartModel = iterator.next();

			// 合并方式
			ConsolFun consolFun = robinChartModel.getConsolFun();
			if (consolFun == null) {
				consolFun = DEFAULT_CONSOL_FUN;
			}

			// 曲线颜色
			Color color = robinChartModel.getColor();
			if (color == null) {
				color = colors[i % colors.length];
			}

			// 曲线说明
			String legend = robinChartModel.getLegend();
			// 曲线形状
			ChartSeries chartSeries = robinChartModel.getChartSeries();

			// 数据源名称
			String dsName = robinChartModel.getDsName();
			// 曲线标识
			String lineName = dsName + "_" + consolFun.toString();

			String rrdPath = robinChartModel.getRrdPath();
			//如果robinChartModel未指定rrdPath，则使用JRobinGraphingParam对象的rrdPath
			if (rrdPath == null || rrdPath.trim().length() == 0){
				rrdPath = defaultRrdPath;
			}
			// 加入该曲线的相关数据
			graphDef
					.datasource(lineName, rrdPath, dsName, consolFun.toString());

			// 根据每行显示几个legend，加入换行符
			if ((i + 1) % legendColumns == 0) {
				legend += "\n";
			}
			// 绘制曲线
			graphingChar(graphDef, chartSeries, lineName, color, legend);
		}

		// 注释
		graphDef.comment(graphingParam.getComment());

		// 图形
		rrdGraph = new RrdGraph(graphDef);

		return rrdGraph;
	}

	/**
	 * 绘制一条曲线到graphDef
	 * 
	 * @param graphDef 定义图形的对象
	 * @param chartSeries 线型
	 * @param dsName 
	 * @param color
	 * @param legend
	 * @throws RrdException
	 */
	private static void graphingChar(RrdGraphDef graphDef,
			ChartSeries chartSeries, String dsName, Color color, String legend)
			throws RrdException {
		if (chartSeries == null) {
			chartSeries = DEFAULT_CHART_SERIES;
		}

		// 根据不同的图形形状类别，调用不同的方法
		if (chartSeries.equals(ChartSeries.LINE)) {
			graphDef.line(dsName, color, legend);
		} else if (chartSeries.equals(ChartSeries.AREA)) {
			graphDef.area(dsName, color, legend);
		} else if (chartSeries.equals(ChartSeries.STACK)) {
			graphDef.stack(dsName, color, legend);
		}
	}

	/**
	 * 按默认宽高，生成图片文件
	 * 
	 * @param rrdGraph 
	 * @param graphFormat
	 * @param graphingPath
	 * @throws RrdException
	 * @throws IOException
	 */
	private static void saveGraph(RrdGraph rrdGraph, GraphFormat graphFormat,
			String graphingPath) throws RrdException, IOException {
		if (graphFormat == null) {
			graphFormat = DEFAULT_GRAPH_FORMAT;
		}

		if (graphFormat.equals(GraphFormat.PNG)) {
			rrdGraph.saveAsPNG(graphingPath);
		} else if (graphFormat.equals(GraphFormat.GIF)) {
			rrdGraph.saveAsGIF(graphingPath);
		} else if (graphFormat.equals(GraphFormat.JPEG)) {
			rrdGraph.saveAsJPEG(graphingPath, 0.5f);
		}
	}

	/**
	 * 按指定宽高生成图片文件
	 * 
	 * @param rrdGraph
	 * @param graphFormat
	 * @param width
	 * @param height
	 * @param quality
	 * @param graphingPath
	 * @throws RrdException
	 * @throws IOException
	 */
	private static void saveGraph(RrdGraph rrdGraph, GraphFormat graphFormat,
			int width, int height, float quality, String graphingPath)
			throws RrdException, IOException {
		if (graphFormat == null) {
			graphFormat = DEFAULT_GRAPH_FORMAT;
		}

		if (graphFormat.equals(GraphFormat.PNG)) {
			rrdGraph.saveAsPNG(graphingPath, width, height);
		} else if (graphFormat.equals(GraphFormat.GIF)) {
			rrdGraph.saveAsGIF(graphingPath, width, height);
		} else if (graphFormat.equals(GraphFormat.JPEG)) {
			if (quality == 0) {
				quality = 0.5f;
			}
			rrdGraph.saveAsJPEG(graphingPath, width, height, quality);
		}
	}

	/**
	 * 按默认宽高，返回图片的字节码
	 * 
	 * @param rrdGraph
	 * @param graphFormat
	 * @return
	 * @throws RrdException
	 * @throws IOException
	 */
	private static byte[] byteGraph(RrdGraph rrdGraph, GraphFormat graphFormat)
			throws RrdException, IOException {
		byte[] bytes = null;

		if (graphFormat == null) {
			graphFormat = DEFAULT_GRAPH_FORMAT;
		}

		if (graphFormat.equals(GraphFormat.PNG)) {
			bytes = rrdGraph.getPNGBytes();
		} else if (graphFormat.equals(GraphFormat.GIF)) {
			bytes = rrdGraph.getGIFBytes();
		} else if (graphFormat.equals(GraphFormat.JPEG)) {
			bytes = rrdGraph.getJPEGBytes(0.5f);
		}
		return bytes;
	}

	/**
	 * 按指定宽高，返回图片的字节码
	 * 
	 * @param rrdGraph
	 * @param graphFormat
	 * @param width
	 * @param height
	 * @param quality
	 * @return
	 * @throws RrdException
	 * @throws IOException
	 */
	private static byte[] byteGraph(RrdGraph rrdGraph, GraphFormat graphFormat,
			int width, int height, float quality) throws RrdException,
			IOException {
		byte[] bytes = null;

		if (graphFormat == null) {
			graphFormat = DEFAULT_GRAPH_FORMAT;
		}

		if (graphFormat.equals(GraphFormat.PNG)) {
			bytes = rrdGraph.getPNGBytes(width, height);
		} else if (graphFormat.equals(GraphFormat.GIF)) {
			bytes = rrdGraph.getGIFBytes(width, height);
		} else if (graphFormat.equals(GraphFormat.JPEG)) {
			if (quality == 0) {
				quality = 0.5f;
			}
			bytes = rrdGraph.getJPEGBytes(width, height, quality);
		}
		return bytes;
	}