Java SHA1 实现

private static final String ENCODE = "UTF-8";
    
private static MessageDigest sha1MD;

public static String SHA1(String text){
	Log.d(TAG, "@SHA1 text:" +text);
	if(null == sha1MD){
	    try {
		sha1MD = MessageDigest.getInstance("SHA-1");
	    } catch (NoSuchAlgorithmException e) {
	        Log.e(TAG, "@SHA1 No such SHA-1 algorithm.");
		return null;
	    }   
	}
	try {
	    sha1MD.update(text.getBytes(ENCODE), 0, text.length());
	} catch (UnsupportedEncodingException e) {
	    sha1MD.update(text.getBytes(), 0, text.length());
	}
	return toHexString(sha1MD.digest());
    }
    
    private static String toHexString(byte [] hashs){
	StringBuffer sBuffer = new StringBuffer();
	for(byte hash : hashs){
	    sBuffer.append(Integer.toString(( hash & 0xFF ) + 0x100, 16).substring( 1 )); 
	}
	return sBuffer.toString();
    }