Plotting Jonathan's pink dots using Netbeans 5.5 Visual Web Pack

You must be impressed by the Jonathan's pink dots showing the worldwide Solaris growth. It would be equally impressive if we could create the pink dots Google Map mashup using Netbeans - Sun's another successful product. Yes, it is very simple  to create such mashup using Netbeans 5.5 Visual Web Pack AJAX components with as few as 10-20 lines of pure Java code. Also, it is possible to make the mashup much more interactive, like providing a dropdown list to select the dots only in particular country or show the dots only above or below certain threshold value.

Here is how you can do it.

• Create a Netbeans 5.5 Visual web pack project.   
• Download and install the AJAX components
• From the Palette Drag and drop AJAX map (Google) viewer component
  (See Using the AJAX Map Viewer Component  tutorial on how to use this component)

Assume you have some data  like city, country and some reletaded data to plot. Ex:

"Oxford, United Kingdom", 105663 
"Louisville, Kentucky, United States", 85108

In order to plot this using the VWP Google map viewer component, you must first convert the city, country  information to corresponding Latitude and Longitude. This can be easily done by writing a simple web service using Netbeans. Now the converted data would look like

"Oxford, United Kingdom", 105663, 51.75, -1.2599
"Louisville; Kentucky; United States", 85108, 38.24, -85.7699

Once we include the Latitude & Longitude of the cities in the data, it is very easy to plot the data. After following the tutorial Using the AJAX Map Viewer Component , the additional code you need is to place the markers corresponding to different cities. Following are the additional few lines of code I added to the "prerender" method of the page bean.

        int maxCount = 2000;
        markers = new MapMarker[maxCount];
        ServletContext context = (ServletContext) getExternalContext().getContext();
        String realPath = context.getRealPath("/resources/sample_data.txt");
        try{
            BufferedReader in = new BufferedReader(new FileReader(realPath));
            String str;
            while ((str = in.readLine()) != null) {
                String[] data = str.split(",");
                markers[count] =  new MapMarker();
                markers[count].setLatitude(Double.valueOf(data[2]).doubleValue());
                markers[count].setLongitude(Double.valueOf(data[3]).doubleValue());
                markers[count].setMarkup(data[1]);
                if(count++ > maxCount) break;
            }
        }catch (Exception exc) {
            log(exc.getLocalizedMessage();
        }
        

It is possible to show the intensity at a point by using different icons (like various shades and size of dots) for the marker. I used just the default icon for the markers and some dummy data for the locations (I don't have the actual pink dots data). The plots looked like the pictures below

Posted at 10:55AM Jan 12, 2007  |  Permanent link to this entry