J2ME下载并显示网络图片教程

j2me如何从网上下载一张图片，然后绘制出来

Image getImageFromURL(String url){
        byte[] result = null;
        HttpConnection hcon;
        DataOutputStream os;
        DataInputStream is = null;
        int length = 0;
        try {
            hcon = (HttpConnection) Connector.open(url, Connector.READ_WRITE);
            hcon.setRequestMethod(HttpConnection.POST);
            hcon.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
            os = hcon.openDataOutputStream();
            int rc = hcon.getResponseCode();
            if(rc == HttpConnection.HTTP_OK)
            {
                is = new DataInputStream(hcon.openDataInputStream());
                length = (int) hcon.getLength();
                byte[] b = new byte[length];

                System.out.println(" length="+length);
                int index =0, hasRead=0;
                while(hasRead!=-1 && index<length){
                    hasRead = is.read(b, index, length-index);
                    index += hasRead;
                    System.out.println(" hasRead:"+hasRead);
                }
                result = b;
            }
            is.close();