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I am new to Java but needs to know that if it is possible for a developer so that he/she can change the shape of the JProgressBar. I mean suppose in my case I want to change the shape so that it looks like a circle or something else?
Though I just want it to be changed from a bar shape to an arc shape or you can say i want to change the bar shape into any other shape. My progress bar may look like a curve other than a bar shape. I want to add a curve in it.
The appearance of a JProgressBar is controlled by the component's UI delegate, typically derived from BasicProgressBarUI. You can supply your own delegate, as shown here, and override the desired paint method.
Addendum: For a semi-circular display, you may be able to leverage DialPlot from the JFreeChart library. A complete example is discussed here. You can use it directly or render the chart in your UI delegate.
来源：https://stackoverflow.com/questions/16182705/change-shape-of-jprogressbar