fix for issue #97 non closing write operation in XChartPanel - saveJPGWithQuality

xchart/src/main/java/com/xeiam/xchart/BitmapEncoder.java

@@ -72,7 +72,8 @@ public final class BitmapEncoder {
   }
 
   /**
-   * Save a chart as a PNG with a custom DPI. The default DPI is 72, which is fine for displaying charts on a computer monitor, but for printing charts, a DPI of around 300 is much better.
+   * Save a chart as a PNG with a custom DPI. The default DPI is 72, which is fine for displaying charts on a computer monitor, but for printing
+   * charts, a DPI of around 300 is much better.
    *
    * @param chart
    * @param fileName
@@ -83,7 +84,8 @@ public final class BitmapEncoder {
 
     double scaleFactor = DPI / 72.0;
 
-    BufferedImage bufferedImage = new BufferedImage((int) (chart.getWidth() * scaleFactor), (int) (chart.getHeight() * scaleFactor), BufferedImage.TYPE_INT_RGB);
+    BufferedImage bufferedImage = new BufferedImage((int) (chart.getWidth() * scaleFactor), (int) (chart.getHeight() * scaleFactor),
+        BufferedImage.TYPE_INT_RGB);
 
     Graphics2D graphics2D = bufferedImage.createGraphics();
 
@@ -164,10 +166,14 @@ public final class BitmapEncoder {
     iwp.setCompressionQuality(quality);
     File file = new File(fileName);
     FileImageOutputStream output = new FileImageOutputStream(file);
+    try {
       writer.setOutput(output);
       IIOImage image = new IIOImage(bufferedImage, null, null);
       writer.write(null, image, iwp);
       writer.dispose();
+    } finally {
+      output.close();
+    }
   }
 
   /**