Make SHA1 encryption on Android?

Question

Can you suggest me about how to encrypt string using SHA1 algorithm ? I've searched about it. But no luck.

Thanks in advance.

Answer 1

binnyb's convertToHex method is not working properly. A more correct one that works for me is:

private static String convertToHex(byte[] data) { 
    StringBuffer buf = new StringBuffer();
    for (int i = 0; i < data.length; i++) { 
        int halfbyte = (data[i] >>> 4) & 0x0F;
        int two_halfs = 0;
        do { 
            if ((0 <= halfbyte) && (halfbyte <= 9)) {
                buf.append((char) ('0' + halfbyte));
            }
            else {
                buf.append((char) ('a' + (halfbyte - 10)));
            }
            halfbyte = data[i] & 0x0F;
        } while(two_halfs++ < 1);
    } 
    return buf.toString();
} 


public static String SHA1(String text) throws NoSuchAlgorithmException, UnsupportedEncodingException  { 
    MessageDigest md = MessageDigest.getInstance("SHA-1");
    byte[] sha1hash = new byte[40];
    md.update(text.getBytes("iso-8859-1"), 0, text.length());
    sha1hash = md.digest();
    return convertToHex(sha1hash);
} 

use the SHA1 method to get your sha1 string.

Update: providing a complete answer

Answer 2

here are 2 methods i have found while searching for a sha1 algorithm implementation:

private static String convertToHex(byte[] data) { 
    StringBuffer buf = new StringBuffer();
    int length = data.length;
    for(int i = 0; i < length; ++i) { 
        int halfbyte = (data[i] >>> 4) & 0x0F;
        int two_halfs = 0;
        do { 
            if((0 <= halfbyte) && (halfbyte <= 9)) 
                buf.append((char) ('0' + halfbyte));
            else 
                buf.append((char) ('a' + (halfbyte - 10)));
            halfbyte = data[i] & 0x0F;
        }
        while(++two_halfs < 1);
    } 
    return buf.toString();
}

public static String SHA1(String text) throws NoSuchAlgorithmException, UnsupportedEncodingException  { 
    MessageDigest md = MessageDigest.getInstance("SHA-1");
    byte[] sha1hash = new byte[40];
    md.update(text.getBytes("iso-8859-1"), 0, text.length());
    sha1hash = md.digest();
    return convertToHex(sha1hash);
} 

use the SHA1 method to get your sha1 string. I have not confirmed that this is indeed a sha1, but it works for my apps.