I would like to display a temperature curve over time. I have now read a file, which is CSV-similar, that let me know the time and the temperature indicated. Now I want to use JFreeChart to display an XY graph from the values. The original data of the file looks as follows:
utc,local,celsius
2017-07-12T07:02:53+00:00,2017-07-12T09:02:53+02:00,26.25
2017-07-12T08:02:54+00:00,2017-07-12T10:02:54+02:00,26.08
2017-07-12T09:02:55+00:00,2017-07-12T11:02:55+02:00,25.78
2017-07-12T10:02:56+00:00,2017-07-12T12:02:56+02:00,25.96
2017-07-12T10:51:02+00:00,2017-07-12T12:51:02+02:00,26.14
2017-07-12T10:51:02+00:00,2017-07-12T12:51:02+02:00,26.14
The output of time & temperature values (I have separated from the original file) looks like:
09:02:53,26.25
10:02:54,26.08
11:02:55,25.78
12:02:56,25.96
12:51:02,26.14
12:51:02,26.14
EDIT: Now I have inserted a DateTimeFormatter in the example from Trashgod: It looks like:
public class Test {
public static void main(String[] args) {
EventQueue.invokeLater(() -> {
ApplicationFrame frame = new ApplicationFrame("CSVTest");
Test test = new Test();
frame.add(test.createChart("Temperature profile"));
frame.pack();
frame.setLocationRelativeTo(null);;
frame.setVisible(true);
});
}
private ChartPanel createChart(String chartTitle) {
JFreeChart chart = ChartFactory.createTimeSeriesChart(chartTitle,
"Time", "Temperature", createDataset(), true, true, false);
ChartPanel chartPanel = new ChartPanel(chart);
XYPlot plot = chart.getXYPlot();
DateAxis domain = (DateAxis) plot.getDomainAxis();
domain.setDateFormatOverride(DateFormat.getDateInstance());
plot.setBackgroundPaint(Color.WHITE);
return chartPanel;
}
private XYDataset createDataset() {
TimeSeries series = new TimeSeries("Temperature");
TimeSeriesCollection dataset = new TimeSeriesCollection(series);
try (FileReader fr = new FileReader("TestCSV.csv");
BufferedReader br = new BufferedReader(fr)) {
String line;
br.readLine();
while ((line = br.readLine()) != null) {
String[] split = line.split(",");
System.out.println(ZonedDateTime.parse(split[1]).format(DateTimeFormatter.ISO_LOCAL_TIME) + "," +split[2]);
ZonedDateTime zdt = ZonedDateTime.of(LocalDate.now(),LocalTime.parse(split[0]), ZoneId.systemDefault());
String s = ZonedDateTime.parse(split[0]).format(DateTimeFormatter.ISO_LOCAL_TIME);
Second second = new Second(Date.from(zdt.toInstant()));
series.add(second, Double.valueOf(split[1]));
}
} catch (IOException | SeriesException e) {
System.err.println("Error: " + e);
}
return dataset;
}
The first line of the "CSV" -like file is still displayed 09:02:53,26.25 Then I get a DateTimeParseException: Text '2017-07-12T09:02:53+02:00' could not be parsed at index 2
Exception in thread "AWT-EventQueue-0" java.time.format.DateTimeParseException: Text '2017-07-12T07:02:53+00:00' could not be parsed at index 2
at java.time.format.DateTimeFormatter.parseResolved0(Unknown Source)
at java.time.format.DateTimeFormatter.parse(Unknown Source)
at java.time.LocalTime.parse(Unknown Source)
at java.time.LocalTime.parse(Unknown Source)
at org.jfree.chart.demo.Test.createDataset(Test.java:63)
at org.jfree.chart.demo.Test.createChart(Test.java:43)
at org.jfree.chart.demo.Test.lambda$0(Test.java:34)
Why can not the rest of the file be read nor displayed? ("System.out.println()" should only serve as a control at the end). The DateTimeFomatter is correct, isn´t it?
With your approach, the time to make locally I come no further & the program can not translate. What did I do wrong? How could it work if the direct output
09:02:53,26.25
10:02:54,26.08
11:02:55,25.78
12:02:56,25.96
12:51:02,26.14
12:51:02,26.14
is displayed in a chart? I think to split and to transform like I did is okay, isn´t it? Now I have setDateFormatOverride () in the code, but the error message, as well as the output remain the same.
Several problems are evident:
You never add anything to lines
; at a minimum, you'll need something like this:
lines.add(line);
Instead of ChartFactory.createXYLineChart()
, consider creating a time series:
ChartFactory.createTimeSeriesChart(…)
The XYDataset
returned by createDataset()
should be a TimeSeriesCollection
to which you add a TimeSeries
.
In createDataset()
, iterate though lines
, parse the data fields, and add the values to the TimeSeries
.
The time values given are most closely modeled by LocalTime
, but TimeSeries
expects to add()
coordinates defined by a RegularTimePeriod
and a double
; see Legacy Date-Time Code concerning the conversion shown below.
Note that TimeSeries
throws SeriesException
for duplicate domain values; as a result, only three of the four lines int eh sample input air charted.
Instead of replacing the factory supplied XYLineAndShapeRenderer
, get a reference to it for later modification.
Alter the chart's size using one of the approaches shown here.
Avoid extending top-level containers line ApplicationFrame
.
Construct and manipulate Swing GUI objects only on the event dispatch thread.
Use a try-with-resources statement to ensure that each resource is closed at the end of the statement.
As your actual data contains ISO 8601 dates, ZonedDateTime.parse()
can be used directly; use setDateFormatOverride()
to format the date axis labels; the example below specifies a UTC time zone in ISO 8601 format for easy comparison; comment out the call to setDateFormatOverride()
to see the times in your local time zone.
import java.awt.Color;
import java.awt.EventQueue;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.time.ZonedDateTime;
import java.util.Date;
import java.util.TimeZone;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.DateAxis;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.data.general.SeriesException;
import org.jfree.data.time.Second;
import org.jfree.data.time.TimeSeries;
import org.jfree.data.time.TimeSeriesCollection;
import org.jfree.data.xy.XYDataset;
import org.jfree.ui.ApplicationFrame;
/** @see https://stackoverflow.com/a/45173688/230513 */
public class CSVTest {
public static void main(String[] args) {
EventQueue.invokeLater(() -> {
ApplicationFrame frame = new ApplicationFrame("CSVTest");
CSVTest test = new CSVTest();
frame.add(test.createChart("Temperature profile"));
frame.pack();
frame.setLocationRelativeTo(null);;
frame.setVisible(true);
});
}
private ChartPanel createChart(String chartTitle) {
JFreeChart chart = ChartFactory.createTimeSeriesChart(chartTitle,
"Time", "Temperature", createDataset(), true, true, false);
ChartPanel chartPanel = new ChartPanel(chart);
XYPlot plot = chart.getXYPlot();
plot.setBackgroundPaint(Color.WHITE);
XYLineAndShapeRenderer r = (XYLineAndShapeRenderer) plot.getRenderer();
r.setBaseShapesVisible(true);
DateAxis axis = (DateAxis) plot.getDomainAxis();
SimpleDateFormat df = new SimpleDateFormat("HH:mm:ssX");
df.setTimeZone(TimeZone.getTimeZone("UTC"));
axis.setDateFormatOverride(df);
return chartPanel;
}
private XYDataset createDataset() {
TimeSeries series = new TimeSeries("Temperature");
TimeSeriesCollection dataset = new TimeSeriesCollection(series);
try (FileReader fr = new FileReader("temp.csv");
BufferedReader br = new BufferedReader(fr)) {
String line;
while ((line = br.readLine()) != null) {
String[] s = line.split(",");
ZonedDateTime zdt = ZonedDateTime.parse(s[0]);
Second second = new Second(Date.from(zdt.toInstant()));
series.add(second, Double.valueOf(s[2]));
}
} catch (IOException | SeriesException e) {
System.err.println("Error: " + e);
}
return dataset;
}
}