Produce a Hex Dump of the Contents of a URL

This program opens connection with a specified URL and hex-dumps the contents received from an associated input stream. Use this to find out what’s going on with your browser.

public class UrlHexDump {   static final char[] hexes = "0123456789abcdef".toCharArray();   public static String toHex(int value, int length) {     StringBuffer b = new StringBuffer(length);     while(length-- > 0) {       b.append(hexes[value & 0xf]);       value >>= 4;     }     return b.reverse().toString();   }   public static void main(String[] args) {     try {       URL url = new URL(args[0]);       URLConnection connection = url.openConnection();       InputStream is = connection.getInputStream();       int n = connection.getContentLength();       String type = connection.getContentType();       System.out.println(type + ": " + n + " bytes.");       for (int i = 0; i < n; i++) {         int b = is.read();         if (b < 0) break;         if ((i) % 32 == 0) System.out.print("
[" + toHex(i, 4) + "] ");         System.out.print(" " + toHex(b & 0xff, 2));       }       System.out.println();     }     catch (IOException ex) {       System.err.println("error: " + ex);     }   }}

Charlie Frank

Charlie has over a decade of experience in website administration and technology management. As the site admin, he oversees all technical aspects of running a high-traffic online platform, ensuring optimal performance, security, and user experience.