Sets the delegate <code>Authenticator</code> instance that this SecurityManager uses to perform all
authentication operations. Unless overridden by this method, the default instance is a
{@link hunt.shiro.authc.pam.ModularRealmAuthenticator ModularRealmAuthenticator}.
@param authenticator the delegate <code>Authenticator</code> instance that this SecurityManager will use to
perform all authentication operations.
@throws IllegalArgumentException if the argument is <code>null</code>.
Sets the delegate <code>Authenticator</code> instance that this SecurityManager uses to perform all authentication operations. Unless overridden by this method, the default instance is a {@link hunt.shiro.authc.pam.ModularRealmAuthenticator ModularRealmAuthenticator}.
@param authenticator the delegate <code>Authenticator</code> instance that this SecurityManager will use to perform all authentication operations. @throws IllegalArgumentException if the argument is <code>null</code>.