public static String renderChart(JFreeChart chart, String fileName) {
String imageFile = "";
try {
final ChartRenderingInfo info = new ChartRenderingInfo(new StandardEntityCollection());
TempDir tempDir = TempDirUtils.createTempDir();
File file1 = tempDir.createFile(fileName);
imageFile = "<IMG SRC=\"file:" + file1.getAbsolutePath() + "\" " + "WIDTH=\"600\" HEIGHT=\"400\" BORDER=\"0\" USEMAP=\"#chart\"></IMG>";
ChartUtilities.saveChartAsPNG(file1, chart, 600, 400, info);
} catch (IOException e) {
System.out.println(e.toString());
}