question: public static String generateSourceID ( String entityID ) { if ( ( entityID == null ) || ( entityID . length ( ) == 0 ) ) { return null ; } MessageDigest md = null ; try { md = MessageDigest . getInstance ( "SHA" ) ; } catch ( NoSuchAlgorithmException e ) { debug . error ( "SAML2Utils.generateSourceID: " , e ) ; return null ; } char chars [ ] = entityID . toCharArray ( ) ; byte bytes [ ] = new byte [ chars . length ] ; for ( int i = 0 ; i < chars . length ; i ++ ) { bytes [ i ] = ( byte ) chars [ i ] ; } md . update ( bytes ) ; return SAML2Utils . byteArrayToString ( md . digest ( ) ) ; }
target:  Generates provider Source ID based on provider Entity ID. The returned is SHA-1 digest string.