@BeforeEach
    public void setUp() {
        filter = createTestInstance();
        chain = mock(FilterChain.class);
        request = mock(ServletRequest.class);
        response = mock(ServletResponse.class);
    }
Unit tests for the {@link OncePerRequestFilter} implementation.

@since 1.2
web/src/test/java/org/apache/shiro/web/servlet/OncePerRequestFilterTest.java