JRobin是一个很强大的存储和用图形展示基于时间序列数据的工具.doc

JRobin是一个很强大的存储和用图形展示基于时间序列数据的工具。只要有合适的需求，能够提供提供满足这些需求的数据，JRobin就能合理地存储这些数据，并且生成非常漂亮的图形。 在基于JRobin的应用中，最主要的工具并不在于JRobin，而是如何设计应用和使用Java代码采用相应的手段获取感兴趣的数据。通过在Java中执行外部命令来获取Ping的响应时间。本文的应用旨在对计算机CPU的使用率进行监视，因为如何在Windows和Linux上获取CPU的使用率就成为了关键要解决的问题。 1、在Windows上获取CPU使用率： WMI提供了在Windows上获取计算机各种有用信息的接口，尤其可以利用WMI来获取计算机性能有关的数据。可以用通过 Win32_Processor对象来获取CPU的使用率，该对象LoadPercentage属性保存了相应CPU的负载情况。在本例中，将计算机上各 个CPU使用率进行简单平均，既是该计算机CPU的使用率。脚本如下： strComputer = . Set objWMIService = GetObject(winmgmts: _ & impersonationLevel=impersonate! & strComputer & rootcimv2) Set colItems = objWMIService.ExecQuery(Select * from Win32_Processor ,48) load = 0 n = 0 For Each objItem in colItems load = load + objItem.LoadPercentage n = n + 1 Next Wscript.Echo (load/n) 该最后脚本输出CPU平均使用率，Java程序可以执行该脚本获取标准输出，得到CPU平均使用率。 2、在Linux上获取CPU使用率： Linux操作系统的/proc文件系统提供了与系统和进程有关的信息。通过访问/proc/stat就可以获取CPU的使用情况。其bash脚本如下： user=cat /proc/stat | head -n 1 | awk print $2 nice=cat /proc/stat | head -n 1 | awk print $3 system=cat /proc/stat | head -n 1 | awk print $4 idle=cat /proc/stat | head -n 1 | awk print $5 iowait=cat /proc/stat | head -n 1 | awk print $6 irq=cat /proc/stat | head -n 1 | awk print $7 softirq=cat /proc/stat | head -n 1 | awk print $8 let used=$user+$nice+$system+$iowait+$irq+$softirq let total=$used+$idle echo $used $total 该脚本最后输出自机器启动以来，CPU总共使用的时间和总共运行时间。要想获取CPU使用率，还需要作进行一步处理。处理步骤如下： （1）运行脚本，得到相应数据：1000 10000 （2）sleep 60秒 （3）运行脚本，得到相应数据：7000 70000 （4）那么在这段时间内，CPU的使用率就等于：（7000 - 1000）/（70000 - 10000）= 10%。 （5）定时运行脚本，就可以得到每个时段CPU的使用率。 3、与获取Ping响应时间代码的异同： 这两个程序实现的功能基本类似，就是获取数据，利用JRobin保存和画图。其中利用JRobin保存和画图的功能除了保存的数据源、显示的文本信息不同以外，其他都是相同的。他们最大的不同在于获取和处理数据的方式。 在WIndows下，Ping程序利用Ping命令来获取数据，而CPU监视程序则使用VBScript利用WMI接口通过CScript.EXE执行脚本来实现。 在Linux下，不能直接获取CPU使用率信息，需要在下一次获取到CPU使用信息时，对数据进行进一步出来才能得到。 4、看看成果： 5、事例代码： import java.awt.Color; import java.awt.Font; import java.io.BufferedReader; import java.io.File; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.util.ArrayList; import java.util.Date; import java.util.List; import java.util.Timer; import java.util.TimerTask; import java.util.logging.Logger; import org.jrobin.core.RrdDb; import org.jrobin.core.RrdDef; import org.jrobin.core.Sample; import org.jrobin.graph.RrdGraph; import org.jrobin.graph.RrdGraphDef; public class CPUMonitor public static String execute(String commands) String strs = null; File scriptFile = null; try List cmdList = new ArrayList(); String osName = System.getProperty(); if (osName.indexOf(Windows) -1) scriptFile = File.createTempFile(monitor, .vbs); cmdList.add(CMD.EXE); cmdList.add(/C); cmdList.add(CSCRIPT.EXE); cmdList.add(/NoLogo); else scriptFile = File.createTempFile(monitor, .sh); cmdList.add(/bin/bash); String fileName = scriptFile.getCanonicalPath(); PrintWriter writer = new PrintWriter(scriptFile); for (int i = 0; i commands.length; i+) writer.println(commandsi); writer.flush(); writer.close(); cmdList.add(fileName); writer.flush(); writer.close(); cmdList.add(fileName); ProcessBuilder pb = new ProcessBuilder(cmdList); Process p = pb.start(); p.waitFor(); String line = null; BufferedReader stdout = new BufferedReader(new InputStreamReader(p .getInputStream(); List stdoutList = new ArrayList(); while (line = stdout.readLine() != null) stdoutList.add(line); BufferedReader stderr = new BufferedReader(new InputStreamReader(p .getErrorStream(); List stderrList = new ArrayList(); while (line = stderr.readLine() != null) stderrList.add(line); strs = stdoutList.toArray(new String0); catch (Exception e) e.printStackTrace(); finally if (scriptFile != null) scriptFile.delete(); return strs; private String dataFormat = %3f; private Logger logger = Logger.getLogger(this.getClass().getName(); private String monitorName = cpu; private String dataDir = .; private int step = 10; private String rrdPath = ; private Timer timer = new Timer(); private long timeStart = 0; protected int width = 600; protected int height = 150; public CPUMonitor(String dataDir, int step) this.dataDir = dataDir; this.step = step; this.rrdPath = this.dataDir + File.separator + monitorName + .rrd; public String generateGraph() long timeCur = org.jrobin.core.Util.getTimestamp(); return generateGraph(timeStart, timeCur); public String generateGraph(long start, long end) RrdDb rrdDb = null; try Color colors = new Color Color.GREEN, Color.BLUE, Color.MAGENTA, Color.YELLOW, Color.RED, Color.CYAN, Color.ORANGE, Color.PINK, Color.BLACK ; String graphPath = this.dataDir + File.separator + monitorName + .png; / create graph (Creating graph); RrdGraphDef gDef = new RrdGraphDef(); gDef.setWidth(width); gDef.setHeight(height); gDef.setFilename(graphPath); gDef.setStartTime(start); gDef.setEndTime(end); gDef.setTitle(CPU Usage); gDef.setVerticalLabel(%); String dsNames = null; rrdDb = new RrdDb(rrdPath); dsNames = rrdDb.getDsNames(); for (int i = 0; i dsNames.length; i+) String dsName = dsNamesi; String legend = dsName; if (legend = null | legend.equals() legend = dsName; gDef.datasource(dsName, rrdPath, dsName, AVERAGE); gDef.line(dsName, colorsi % colors.length, legend, 2); gDef.gprint(dsName, MIN, dataFormat + Min); gDef.gprint(dsName, AVERAGE, dataFormat + Avg); gDef.gprint(dsName, MAX, dataFormat + Max); gDef.gprint(dsName, LAST, dataFormat + Lastr); gDef.print(dsName, MIN, min + dsName + = %.3f); gDef.print(dsName, AVERAGE, avg + dsName + = %.3f); gDef.print(dsName, MAX, max + dsName + = %.3f); gDef.print(dsName, LAST, last + dsName + = %.3f); gDef.setImageInfo(); gDef.setPoolUsed(false); gDef.setImageFormat(png); gDef.setSmallFont(new Font(Monospaced, Font.PLAIN, 11); gDef.setLargeFont(new Font(SansSerif, Font.BOLD, 14); / gDef.setAltYMrtg(true); / create graph finally RrdGraph graph = new RrdGraph(gDef); / (graph.getRrdGraphInfo().dump(); (Graph created); return graph.getRrdGraphInfo().getFilename(); catch (Exception e) logger.warning(Error in generating graph: + e.getMessage(); finally if (rrdDb != null) try rrdDb.close(); catch (IOException e) e.printStackTrace(); return null; private long lastUsed = 0; private long lastTotal = 0; private double getCPUUsage(String strs) double value = Double.NaN; String osName = System.getProperty(); if (osName.indexOf(Windows) -1) String strValue = strs0; value = Double.parseDouble(strValue); else String strValue = strs0; String values = strValue.split( ); if (values.length = 2) long used = Long.parseLong(values0); long total = Long.parseLong(values1); if (lastUsed 0 & lastTotal 0) long deltaUsed = used - lastUsed; long deltaTotal = total - lastTotal; if (deltaTotal 0) value = (long) (deltaUsed * 100) / deltaTotal) * 10) / 10; lastUsed = used; lastTotal = total; return value; /* * Return a HashMap which contains the current value of each data source. * * return the current value of each data source.*/ public double getValue(String dsName) String commands = new String0; String osName = System.getProperty(); if (osName.indexOf(Windows) -1) commands = new String strComputer = ., Set objWMIService = GetObject(winmgmts: _, & impersonationLevel=impersonate! & strComputer & rootcimv2), Set colItems = objWMIService.ExecQuery(Select * from Win32_Processor ,48), load = 0, n = 0, For Each objItem in colItems, load = load + objItem.LoadPercentage, n = n + 1, Next, Wscript.Echo (load/n) ; else commands = new String user=cat /proc/stat | head -n 1 | awk print $2, nice=cat /proc/stat | head -n 1 | awk print $3, system=cat /proc/stat | head -n 1 | awk print $4, idle=cat /proc/stat | head -n 1 | awk print $5, iowait=cat /proc/stat | head -n 1 | awk print $6, irq=cat /proc/stat | head -n 1 | awk print $7, softirq=cat /proc/stat | head -n 1 | awk print $8, let used=$user+$nice+$system+$iowait+$irq+$softirq, let total=$used+$idle, echo $used $total ; return getCPUUsage(execute(commands); /* * Initialization. */ public void initialize() throws Exception RrdDb rrdDb = null; try rrdDb = new RrdDb(rrdPath); catch (Exception e) if (rrdDb = null) (RRD data is not located in + rrdPath + , create a new one); RrdDef rrdDef = new RrdDef(rrdPath, timeStart - 1, step); rrdDef.addDatasource(cpu, GAUGE, 2 * step, 0, Double.NaN); rrdDef.addArchive(AVERAGE, 0.5, 1, 24 * 3600 / step); rrdDef.addArchive(AVERAGE, 0.5, 300 / step, 7 * 288); (Estimated file size: + rrdDef.getEstimatedSize(); rrdDb = new RrdDb(rrdDef); (RRD file created.); (monitorName + RRD Db Defs: + rrdDb.getRrdDef().dump(); if (rrdDb != null) rrdDb.close(); /* * Start monitor. * * return true if succeed, else false. */ public boolean start() (start to monitor + monitorName); try timeStart = org.jrobin.core.Util.getTimestamp(); initialize(); timer.scheduleAtFixedRate(new TimerTask() public void run() try updateData(); catch (Exception e) e.printStackTrace(); logger.severe(Timer running error: + e.getMessage(); , 0, step * 1000); return true; catch (Exception e) e.printStackTrace(); return false; /* * Stop monitor. */ public void stop() timer.cancel(); private void updateData() throws Exception RrdDb rrdDb = null;