### Question:
KeycloakAuthenticationProvider implements AuthenticationProvider { @Override public boolean supports(Class<?> aClass) { return KeycloakAuthenticationToken.class.isAssignableFrom(aClass); }  void setGrantedAuthoritiesMapper(GrantedAuthoritiesMapper grantedAuthoritiesMapper); @Override Authentication authenticate(Authentication authentication); @Override boolean supports(Class<?> aClass);  }### Answer:
@Test public void testSupports() throws Exception { assertTrue(provider.supports(KeycloakAuthenticationToken.class)); assertFalse(provider.supports(PreAuthenticatedAuthenticationToken.class)); }