Added test for state

Author: gkatzioura

java/sqlcommenter-java/src/test/java/com/google/cloud/sqlcommenter/filter/SpringSQLCommenterWebFilterTest.java

@@ -0,0 +1,40 @@
+package com.google.cloud.sqlcommenter.filter;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+import org.springframework.mock.http.server.reactive.MockServerHttpRequest;
+import org.springframework.mock.web.server.MockServerWebExchange;
+import org.springframework.web.reactive.result.method.RequestMappingInfo;
+import org.springframework.web.reactive.result.method.annotation.RequestMappingHandlerMapping;
+import org.springframework.web.server.WebFilterChain;
+
+import reactor.core.publisher.Mono;
+import reactor.test.StepVerifier;
+
+
+@RunWith(JUnit4.class)
+public class SpringSQLCommenterWebFilterTest {
+
+    @Test
+    public void testPreHandlePlacesStateInContextView() throws NoSuchMethodException {
+        RequestMappingHandlerMapping requestMappingHandlerMapping = new RequestMappingHandlerMapping();
+        RequestMappingInfo info = RequestMappingInfo.paths("/test").build();
+        requestMappingHandlerMapping.registerMapping(info, this, SpringSQLCommenterWebFilterTest.class.getMethod("testPreHandlePlacesStateInContextView"));
+
+        SpringSQLCommenterWebFilter springSQLCommenterWebFilter = new SpringSQLCommenterWebFilter(requestMappingHandlerMapping);
+
+        WebFilterChain filterChain = filterExchange -> Mono.empty();
+
+        MockServerWebExchange exchange = MockServerWebExchange.from(
+                MockServerHttpRequest
+                        .get("/test"));
+
+        StepVerifier.create(springSQLCommenterWebFilter.filter(exchange, filterChain))
+                .expectAccessibleContext()
+                .hasKey("state")
+                .then()
+                .verifyComplete();
+    }
+
+}