Hex Code Matching

Question

hi !
I am taking the hex code of a file and then I match the hex code of the file with a string. There is a problem in matching.
I have used a function that returns true if match is found. The string that I want to match is : 8B5604B1F0224E060AC1B43DCD21.
I have tried using other strings and for those the code works fine. Also, the files that I am matching with 8B5604B1F0224E060AC1B43DCD21 are exe's and when I open them using any hex editor, I can see that string.
Any ideas why this is happening ?
Thanks
Mudit

Answer 1

This is the code which generates the hex code of selected file :
public static StringBuffer displayBinaryFile2(File f) throws IOException
String hex="";
StringBuffer hex2=new StringBuffer();
BufferedInputStream in = new BufferedInputStream(new FileInputStream(f));
String z="0";
int b,i=0,c=0;
int count=0;
while ((b = in.read()) != -1) {
c++;
try {
hex=Integer.toHexString(b);
if (hex.length() == 1)
{hex = '0' + hex;}
hex2=hex2.append(hex);//hex2+hex;
} catch(Exception e){System.out.println("Example5.java"+e);}
in.close();
return hex2;
When I use this code for an exe, the hex code is generated. Next, I match it with a string. The string is present in the hex code as I've found it in hex editor. But still my program does not find the string in the hex code. Has it something to do with internal representation of hex code of exe or what ?
Please help people -- I am in real trouble