Need help loading base64 encoded image.

Question

I've got an applet that saves an image into a database by posting a base64 encoded version of the image to an ASP page. Basically, I convert the image to an array of bytes, then encode it and post it to the page. Now, my problem occurs after I read the base64 string from the database and try to display it. When the application is started up, it is supposed to read the image and load it into the canvas of the applet, but I get a NullPointerException when I call displayImage because the fgImage has -1 width and height. If anyone has done this before and has any hints or tips, that would be great. Otherwise, take a look at my code and see if you can find something wrong. Thanks!
public void loadBase64Image(int[] newPixels) {
System.out.println("loading new image...");
try {
if (newPixels == null) {
byte[] imgPixels = new byte[this.getWidth() * this.getHeight() * 4];
URL loadURL = new URL(fgImgURL);
URLConnection imageCon = loadURL.openConnection();
imageCon.setDoOutput( true );
imageCon.setUseCaches(false);
DataInputStream imageIn = new DataInputStream( imageCon.getInputStream() );
BASE64Decoder decodedImage = new BASE64Decoder();
imgPixels = decodedImage.decodeBuffer(imageIn);
imageIn.close();
int w = this.getWidth();
int h = this.getHeight();
int imgPix[] = new int[w * h];
int index = 0;
for(int y=0; y<imgPix.length;y++){
imgPix[y] = imgPixels[4*y]
| (imgPixels[4*y + 1] >> 8)
| (imgPixels[4*y + 2] >> 16)
| (imgPixels[4*y + 3] >> 24);
imgMemSrc = new MemoryImageSource(w, h, imgPix, 0, w);
else
imgMemSrc = new MemoryImageSource(this.getWidth(),this.getHeight(),newPixels,0,this.getWidth());
// Update the fgImage to the current OSC.
if (fgImage != null) fgImage.flush();
fgImage = Toolkit.getDefaultToolkit().createImage(imgMemSrc);
displayImage(fgImage, this.getWidth(), this.getHeight());
catch (Exception e){
System.out.println("BASE64 LOAD ERROR (" + e.getClass() + ": " + e.getMessage() + ")");

Answer 1

Docs for URLConnection
"A URL connection can be used for input and/or output. Set the DoInput flag to true if you intend to use the URL connection for input, false if not. The default is true unless DoOutput is explicitly set to true, in which case DoInput defaults to false."
You have setDoOutput(true), so doInput is by default set to false according to the docs. I would make the change to also setDoInput(true) as well and see if it works.
public void loadBase64Image(int[] newPixels) {
   System.out.println("loading new image...");
   try {
      if (newPixels == null) {
         byte[] imgPixels = new byte[this.getWidth() * this.getHeight() * 4];
         URL loadURL = new URL(fgImgURL);
         URLConnection imageCon = loadURL.openConnection();
         imageCon.setDoOutput( true );
         imageCon.setDoInput( true ); // Make sure you add this line
         imageCon.setUseCaches(false);
         DataInputStream imageIn = new DataInputStream( imageCon.getInputStream() );
         BASE64Decoder decodedImage = new BASE64Decoder();
         imgPixels = decodedImage.decodeBuffer(imageIn);
         imageIn.close();
         int w = this.getWidth();
         int h = this.getHeight();
         int imgPix[] = new int[w * h];
         int index = 0;
         for(int y=0; y<imgPix.length;y++){
            imgPix[y] = imgPixels[4*y] | (imgPixels[4*y + 1] >> 8) | (imgPixels[4*y + 2] >> 16) | (imgPixels[4*y + 3] >> 24);
         imgMemSrc = new MemoryImageSource(w, h, imgPix, 0, w);
      else
         imgMemSrc = new MemoryImageSource(this.getWidth(),this.getHeight(),newPixels,0,this.getWidth());
      // Update the fgImage to the current OSC.
      if (fgImage != null)
         fgImage.flush();
      fgImage = Toolkit.getDefaultToolkit().createImage(imgMemSrc);
      displayImage(fgImage, this.getWidth(), this.getHeight());
   catch (Exception e){
      System.out.println("BASE64 LOAD ERROR (" + e.getClass() + ": " + e.getMessage() + ")");