1.說明
rrd: A high performance data logging and graphing system for time series data.
rrd4j的jar包下載：http://code.google.com/p/rrd4j/
本例子是官方網站上的Demo
2.官方網站上的源碼Demo
import org.rrd4j.core.*;
import org.rrd4j.graph.RrdGraph;
import org.rrd4j.graph.RrdGraphDef;
import java.awt.*;
import java.io.BufferedOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Random;
import static org.rrd4j.ConsolFun.*;
import static org.rrd4j.DsType.GAUGE;
/**
* Simple demo just to check that everything is OK with this library. Creates two files in your
* $HOME/rrd4j-demo directory: demo.rrd and demo.png.
*/
public class RrdDemo {
static final long SEED = 1909752002L;
static final Random RANDOM = new Random(SEED);
//文件名稱
static final String FILE = "demo";
static final long START = Util.getTimestamp(2010, 4, 1);
static final long END = Util.getTimestamp(2010, 6, 1);
static final int MAX_STEP = 300;
//生成圖片的寬度高度
static final int IMG_WIDTH = 500;
static final int IMG_HEIGHT = 300;
/**
* <p>To start the demo, use the following command:</p>
* <pre>
* java -cp rrd4j-{version}.jar org.rrd4j.demo.Demo
* </pre>
*
* @param args the name of the backend factory to use (optional)
* @throws IOException Thrown
*/
public static void main(String[] args) throws IOException {
println("== Starting demo");
long startMillis = System.currentTimeMillis();
if (args.length > 0) {
println("Setting default backend factory to " + args[0]);
RrdDb.setDefaultFactory(args[0]);
}
long start = START;
long end = END;
//文件路徑
String rrdPath = Util.getRrd4jDemoPath(FILE + ".rrd");
String xmlPath = Util.getRrd4jDemoPath(FILE + ".xml");
String rrdRestoredPath = Util.getRrd4jDemoPath(FILE + "_restored.rrd");
String imgPath = Util.getRrd4jDemoPath(FILE + ".png");
String logPath = Util.getRrd4jDemoPath(FILE + ".log");
PrintWriter log = new PrintWriter(new BufferedOutputStream(new FileOutputStream(logPath, false)));
// first, define the RRD 新建一個RRD定義對象,給定路徑,開始時間以及時間間隔
RrdDef rrdDef = new RrdDef(rrdPath, start - 1, 300);
rrdDef.setVersion(2);
//添加數據源到RRD，通過指定它的數據源名稱、源類型、心跳、最小和最大的值。
//DsType參數 ABSOLUTE COUNTER DERIVE GAUGE
rrdDef.addDatasource("sun", GAUGE, 600, 0, Double.NaN);
rrdDef.addDatasource("shade", GAUGE, 600, 0, Double.NaN);
rrdDef.addArchive(AVERAGE, 0.5, 1, 600);// 1 step, 600 rows
rrdDef.addArchive(AVERAGE, 0.5, 6, 700);// 6 steps, 700 rows
rrdDef.addArchive(AVERAGE, 0.5, 24, 775);
rrdDef.addArchive(AVERAGE, 0.5, 288, 797);
rrdDef.addArchive(TOTAL, 0.5, 1, 600);
rrdDef.addArchive(TOTAL, 0.5, 6, 700);
rrdDef.addArchive(TOTAL, 0.5, 24, 775);
rrdDef.addArchive(TOTAL, 0.5, 288, 797);
rrdDef.addArchive(MAX, 0.5, 1, 600);
rrdDef.addArchive(MAX, 0.5, 6, 700);
rrdDef.addArchive(MAX, 0.5, 24, 775);
rrdDef.addArchive(MAX, 0.5, 288, 797);
println(rrdDef.dump());
log.println(rrdDef.dump());
println("Estimated file size: " + rrdDef.getEstimatedSize());
RrdDb rrdDb = new RrdDb(rrdDef);
println("== RRD file created.");
if (rrdDb.getRrdDef().equals(rrdDef)) {
println("Checking RRD file structure... OK");
} else {
println("Invalid RRD file created. This is a serious bug, bailing out");
return;
}
rrdDb.close();
println("== RRD file closed.");
// update database
GaugeSource sunSource = new GaugeSource(1200, 20);
GaugeSource shadeSource = new GaugeSource(300, 10);
println("== Simulating one month of RRD file updates with step not larger than " +
MAX_STEP + " seconds (* denotes 1000 updates)");
long t = start;
int n = 0;
// then, create a RrdDb from the definition and start adding data
rrdDb = new RrdDb(rrdPath);
Sample sample = rrdDb.createSample();
while (t <= end + 172800L) {
sample.setTime(t);
sample.setValue("sun", sunSource.getValue());
sample.setValue("shade", shadeSource.getValue());
log.println(sample.dump());
sample.update();
t += RANDOM.nextDouble() * MAX_STEP + 1;
if (((++n) % 1000) == 0) {
System.out.print("*");
}
}
rrdDb.close();
println("");
println("== Finished. RRD file updated " + n + " times");
//rrdDb.close();
// test read-only access!
rrdDb = new RrdDb(rrdPath, true);
println("File reopen in read-only mode");
println("== Last update time was: " + rrdDb.getLastUpdateTime());
println("== Last info was: " + rrdDb.getInfo());
// fetch data
println("== Fetching data for the whole month");
FetchRequest request = rrdDb.createFetchRequest(AVERAGE, start, end);
println(request.dump());
log.println(request.dump());
FetchData fetchData = request.fetchData();
println("== Data fetched. " + fetchData.getRowCount() + " points obtained");
println(fetchData.toString());
println("== Dumping fetched data to XML format");
println(fetchData.exportXml());
println("== Fetch completed");
// dump to XML file
println("== Dumping RRD file to XML file " + xmlPath + " (can be restored with RRDTool)");
rrdDb.exportXml(xmlPath);
println("== Creating RRD file " + rrdRestoredPath + " from XML file " + xmlPath);
RrdDb rrdRestoredDb = new RrdDb(rrdRestoredPath, xmlPath);
// close files
println("== Closing both RRD files");
rrdDb.close();
println("== First file closed");
rrdRestoredDb.close();
println("== Second file closed");
// create graph
println("Creating graph " + Util.getLapTime());
println("== Creating graph from the second file");
RrdGraphDef gDef = new RrdGraphDef();
gDef.setWidth(IMG_WIDTH);
gDef.setHeight(IMG_HEIGHT);
gDef.setFilename(imgPath);
gDef.setStartTime(start);
gDef.setEndTime(end);
gDef.setTitle("Temperatures in May-June 2010");
gDef.setVerticalLabel("temperature");
gDef.datasource("sun", rrdRestoredPath, "sun", AVERAGE);
gDef.datasource("shade", rrdRestoredPath, "shade", AVERAGE);
//創建一個新的虛擬數據源通過評估一個數學表達式. name:數據源名稱 rpnExpression：RPN表達式
//平均值
gDef.datasource("median", "sun,shade,+,2,/");
//差值
gDef.datasource("diff", "sun,shade,-,ABS,-1,*");
gDef.datasource("sine", "TIME," + start + ",-," + (end - start) + ",/,2,PI,*,*,SIN,1000,*");
//name:數據源名稱 Color: 顏色 legend：註釋文本
//line：直線 area：區域
gDef.line("sun", Color.GREEN, "sun temp");
gDef.line("shade", Color.BLUE, "shade temp");
gDef.line("median", Color.MAGENTA, "median value");
gDef.area("diff", Color.YELLOW, "difference");
gDef.line("diff", Color.RED, null);
gDef.line("sine", Color.CYAN, "sine fun");
gDef.hrule(2568, Color.GREEN, "hrule");
gDef.vrule((start + 2 * end) / 3, Color.MAGENTA, "vrule\\c");
gDef.comment("\\r");
gDef.gprint("sun", MAX, "maxSun = %.3f%s");
gDef.gprint("sun", AVERAGE, "avgSun = %.3f%S\\c");
gDef.gprint("shade", MAX, "maxShade = %.3f%S");
gDef.gprint("shade", AVERAGE, "avgShade = %.3f%S\\c");
gDef.setImageInfo("<img src='%s' width='%d' height = '%d'>");
gDef.setPoolUsed(false);
gDef.setImageFormat("png");
println("Rendering graph " + Util.getLapTime());
// create graph finally
RrdGraph graph = new RrdGraph(gDef);
println(graph.getRrdGraphInfo().dump());
println("== Graph created " + Util.getLapTime());
// locks info
println("== Locks info ==");
println(RrdSafeFileBackend.getLockInfo());
// demo ends
log.close();
println("== Demo completed in " +
((System.currentTimeMillis() - startMillis) / 1000.0) + " sec");
}
static void println(String msg) {
System.out.println(msg);
}
static void print(String msg) {
System.out.print(msg);
}
static class GaugeSource {
private double value;
private double step;
GaugeSource(double value, double step) {
this.value = value;
this.step = step;
}
long getValue() {
double oldValue = value;
double increment = RANDOM.nextDouble() * step;
if (RANDOM.nextDouble() > 0.5) {
increment *= -1;
}
value += increment;
if (value <= 0) {
value = 0;
}
return Math.round(oldValue);
}
}
}
