Performance problems when iteratively adding points

[xpromache]

I'm using the InvientCharts with Vaadin and I want to make a line chart to which I add a new data point each second.
The problem is that the InvientCharts.addPoint operation takes around 0.5ms x number of points in the graph. Also the getPoints takes around the same time. So by the time i have a few hundreds points in the graph, the thing becomes unusable.
I need to be able to store a few thousands points.

[xpromache]

btw, please see below the stack trace while the getPoints is running.
Basically adding points into a hash involves doing lots of calendar operations.

at sun.util.calendar.BaseCalendar.getCalendarDateFromFixedDate(BaseCalendar.java:434)
at java.util.GregorianCalendar.computeFields(GregorianCalendar.java:2098)
at java.util.GregorianCalendar.computeFields(GregorianCalendar.java:2013)
at java.util.Calendar.setTimeInMillis(Calendar.java:1126)
at java.util.GregorianCalendar.<init>(GregorianCalendar.java:593)
at java.util.Calendar.createCalendar(Calendar.java:1028)
at java.util.Calendar.getInstance(Calendar.java:965)
at com.invient.vaadin.charts.InvientCharts.getDateInMilliseconds(InvientCharts.java:363)
at com.invient.vaadin.charts.InvientCharts.access$0(InvientCharts.java:359)
at com.invient.vaadin.charts.InvientCharts$DateTimePoint.equals(InvientCharts.java:2900)
at java.util.HashMap.put(HashMap.java:393)
at java.util.HashSet.add(HashSet.java:217)
at java.util.AbstractCollection.addAll(AbstractCollection.java:322)
at java.util.LinkedHashSet.<init>(LinkedHashSet.java:169)
at com.invient.vaadin.charts.InvientCharts$Series.getPoints(InvientCharts.java:3173)
at com.invient.vaadin.charts.InvientCharts$DateTimeSeries.getPoints(InvientCharts.java:3647)

[danhallin]

My solution was to create an override of the series class, the updatePointXValuesIfNotPresent-function is called for every addPoint and does a lot of unnecessary work if you have x-values defined on your points:

public class ModifiedDateTimeSeries extends InvientCharts.DateTimeSeries {
...
protected void updatePointXValuesIfNotPresent() {
// do nothing
}
}