JFreeChart Date axis Formatting issue
graphing, java, jfreechart
Solution
According to Adding date/time to JFreeChart graph:
"…you're using `ChartFactory.createXYLineChart()`, which creates a `NumberAxis` for the domain. Instead, use `ChartFactory.createTimeSeriesChart()`, which creates a `DateAxis` for the domain."—trashgod
Problem
I have a time series chart. I have my x-axis as a Date, and the Y-axis are just numbers. I am trying to format the date on the x-axis, however I keep getting exceptions. My code is below: ``` TimeSeries trueSeries = new TimeSeries("True Data"); TimeSeries regressionSeries = new TimeSeries("Regression Line"); TimeSeries averageSeries = new TimeSeries("Moving Average"); for (Date date : regression.keySet()) { Calendar cal = Calendar.getInstance(); cal.setTime(date); int month = cal.get(Calendar.MONTH) + 1; int day = cal.get(Calendar.DAY_OF_MONTH); int year = cal.get(Calendar.YEAR); regressionSeries.add(new Day(day, month, year), regression.get(date)); averageSeries.add(new Day(day, month, year), movingAverage.get(date)); trueSeries.add(new Day(day, month, year), trueData.get(date)); } TimeSeriesCollection dataset = new TimeSeriesCollection(); dataset.addSeries(trueSeries); dataset.addSeries(regressionSeries); dataset.addSeries(averageSeries); JFreeChart chart = ChartFactory.createXYLineChart( stock.getCompanyName() + " (" + stock.getTicker() + ")", "Date", // x-axis Label "Close Price", // y-axis Label dataset, // Dataset PlotOrientation.VERTICAL, // Plot Orientation true, // Show Legend true, // Use tooltips false // Configure chart to generate URLs? ); ``` And then I try to cast the x-axis into a simple date format, as follows: ``` XYPlot plot = (XYPlot) chart.getPlot(); DateAxis axis = (DateAxis) plot.getDomainAxis(); axis.setDateFormatOverride(new SimpleDateFormat("dd-MM-yyyy")); ``` When I run this I get the following exception: java.lang.ClassCastException: org.jfree.chart.axis.NumberAxis cannot be cast to org.jfree.chart.axis.DateAxis Can somebody please tell me what I am doing wrong?