Print cookies in human-readable form in Spring MVC Test

Prior to this commit, when rendering cookies via `andDo(print())` in
Spring MVC Test, the output for the `MockHttpServletResponse` would
look something like the following:

  Cookies = [javax.servlet.http.Cookie@25084a1e]

The reason is that the Cookie class in javax.servlet-api-3.0.1.jar does
not implement toString(). Consequently, nothing about the cookie's
name, value, etc., is displayed, thereby making the debug output for
cookies next to useless.

This commit improves on this by implementing custom toString() logic
for cookies in debug output in Spring MVC Test. For example, the output
now looks like this (without the newlines):

  Cookies = [[Cookie@47faa49c name = 'enigma', value = '42', \\
            comment = [null], domain = [null], maxAge = -1, \\
            path = [null], secure = false, version = 0, \\
            httpOnly = false]]

In addition, this commit fixes a minor bug for FlashMap debug output if
the FlashMap is empty.

Issue: SPR-13168

Author: sbrannen

spring-test/src/main/java/org/springframework/test/web/servlet/result/MockMvcResultHandlers.java

@@ -24,9 +24,10 @@
  * Static, factory methods for {@link ResultHandler}-based result actions.
  *
  * <p><strong>Eclipse users:</strong> consider adding this class as a Java editor
- * favorite. To navigate, open the Preferences and type "favorites".
+ * favorite. To navigate to this setting, open the Preferences and type "favorites".
  *
  * @author Rossen Stoyanchev
+ * @author Sam Brannen
  * @since 3.2
  */
 public abstract class MockMvcResultHandlers {
@@ -49,14 +50,14 @@ public ConsolePrintingResultHandler() {
 				@Override
 				public void printHeading(String heading) {
 					System.out.println();
-					System.out.println(String.format("%20s:", heading));
+					System.out.println(String.format("%s:", heading));
 				}
 				@Override
 				public void printValue(String label, Object value) {
 					if (value != null && value.getClass().isArray()) {
 						value = CollectionUtils.arrayToList(value);
 					}
-					System.out.println(String.format("%20s = %s", label, value));
+					System.out.println(String.format("%17s = %s", label, value));
 				}
 			});
 		}

spring-test/src/main/java/org/springframework/test/web/servlet/result/PrintingResultHandler.java

@@ -18,15 +18,19 @@
 
 import java.util.Enumeration;
 import java.util.Map;
+
+import javax.servlet.http.Cookie;
 import javax.servlet.http.HttpServletRequest;
 
+import org.springframework.core.style.ToStringCreator;
 import org.springframework.http.HttpHeaders;
 import org.springframework.mock.web.MockHttpServletRequest;
 import org.springframework.mock.web.MockHttpServletResponse;
 import org.springframework.test.web.servlet.MvcResult;
 import org.springframework.test.web.servlet.ResultHandler;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
+import org.springframework.util.ObjectUtils;
 import org.springframework.validation.BindingResult;
 import org.springframework.validation.Errors;
 import org.springframework.web.method.HandlerMethod;
@@ -37,10 +41,12 @@
 
 /**
  * Result handler that prints {@link MvcResult} details to the "standard" output
- * stream. An instance of this class is typically accessed via
+ * stream.
+ * <p>An instance of this class is typically accessed via
  * {@link MockMvcResultHandlers#print()}.
  *
  * @author Rossen Stoyanchev
+ * @author Sam Brannen
  * @since 3.2
  */
 public class PrintingResultHandler implements ResultHandler {
@@ -57,7 +63,7 @@ protected PrintingResultHandler(ResultValuePrinter printer) {
 	}
 
 	/**
-	 * @return the result value printer.
+	 * @return the result value printer
 	 */
 	protected ResultValuePrinter getPrinter() {
 		return this.printer;
@@ -198,7 +204,7 @@ protected void printModelAndView(ModelAndView mav) throws Exception {
 	 * Print "output" flash attributes.
 	 */
 	protected void printFlashMap(FlashMap flashMap) throws Exception {
-		if (flashMap == null) {
+		if (ObjectUtils.isEmpty(flashMap)) {
 			this.printer.printValue("Attributes", null);
 		}
 		else {
@@ -220,7 +226,31 @@ protected void printResponse(MockHttpServletResponse response) throws Exception
 		this.printer.printValue("Body", response.getContentAsString());
 		this.printer.printValue("Forwarded URL", response.getForwardedUrl());
 		this.printer.printValue("Redirected URL", response.getRedirectedUrl());
-		this.printer.printValue("Cookies", response.getCookies());
+		printCookies(response.getCookies());
+	}
+
+	/**
+	 * Print the supplied cookies in a human-readable form, assuming the
+	 * {@link Cookie} implementation does not provide its own {@code toString()}.
+	 * @since 4.2
+	 */
+	private void printCookies(Cookie[] cookies) {
+		String[] cookieStrings = new String[cookies.length];
+		for (int i = 0; i < cookies.length; i++) {
+			Cookie cookie = cookies[i];
+			cookieStrings[i] = new ToStringCreator(cookie)
+				.append("name", cookie.getName())
+				.append("value", cookie.getValue())
+				.append("comment", cookie.getComment())
+				.append("domain", cookie.getDomain())
+				.append("maxAge", cookie.getMaxAge())
+				.append("path", cookie.getPath())
+				.append("secure", cookie.getSecure())
+				.append("version", cookie.getVersion())
+				.append("httpOnly", cookie.isHttpOnly())
+				.toString();
+		}
+		this.printer.printValue("Cookies", cookieStrings);
 	}
 
 	protected final HttpHeaders getResponseHeaders(MockHttpServletResponse response) {

spring-test/src/test/java/org/springframework/test/web/servlet/result/PrintingResultHandlerTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2015 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,9 +19,9 @@
 import java.net.URI;
 import java.util.HashMap;
 import java.util.Map;
+
 import javax.servlet.http.Cookie;
 
-import org.junit.Before;
 import org.junit.Test;
 
 import org.springframework.http.HttpHeaders;
@@ -45,33 +45,27 @@
  * Tests for {@link PrintingResultHandler}.
  *
  * @author Rossen Stoyanchev
+ * @author Sam Brannen
  */
 public class PrintingResultHandlerTests {
 
-	private TestPrintingResultHandler handler;
-
-	private MockHttpServletRequest request;
+	private final TestPrintingResultHandler handler = new TestPrintingResultHandler();
 
-	private MockHttpServletResponse response;
+	private final MockHttpServletRequest request = new MockHttpServletRequest("GET", "/") {
+		@Override
+		public boolean isAsyncStarted() {
+			return false;
+		}
+	};
 
-	private StubMvcResult mvcResult;
+	private final MockHttpServletResponse response = new MockHttpServletResponse();
 
+	private final StubMvcResult mvcResult = new StubMvcResult(this.request, null, null,
+			null, null, null, this.response);
 
-	@Before
-	public void setup() {
-		this.handler = new TestPrintingResultHandler();
-		this.request = new MockHttpServletRequest("GET", "/") {
-			@Override
-			public boolean isAsyncStarted() {
-				return false;
-			}
-		};
-		this.response = new MockHttpServletResponse();
-		this.mvcResult = new StubMvcResult(this.request, null, null, null, null, null, this.response);
-	}
 
 	@Test
-	public void testPrintRequest() throws Exception {
+	public void printRequest() throws Exception {
 		this.request.addParameter("param", "paramValue");
 		this.request.addHeader("header", "headerValue");
 
@@ -91,14 +85,23 @@ public void testPrintRequest() throws Exception {
 
 	@Test
 	@SuppressWarnings("deprecation")
-	public void testPrintResponse() throws Exception {
+	public void printResponse() throws Exception {
+		Cookie enigmaCookie = new Cookie("enigma", "42");
+		enigmaCookie.setComment("This is a comment");
+		enigmaCookie.setHttpOnly(true);
+		enigmaCookie.setMaxAge(1234);
+		enigmaCookie.setDomain(".example.com");
+		enigmaCookie.setPath("/crumbs");
+		enigmaCookie.setSecure(true);
+
 		this.response.setStatus(400, "error");
 		this.response.addHeader("header", "headerValue");
 		this.response.setContentType("text/plain");
 		this.response.getWriter().print("content");
 		this.response.setForwardedUrl("redirectFoo");
 		this.response.sendRedirect("/redirectFoo");
 		this.response.addCookie(new Cookie("cookie", "cookieValue"));
+		this.response.addCookie(enigmaCookie);
 
 		this.handler.handle(this.mvcResult);
 
@@ -107,33 +110,46 @@ public void testPrintResponse() throws Exception {
 		headers.setContentType(MediaType.TEXT_PLAIN);
 		headers.setLocation(new URI("/redirectFoo"));
 
-		assertValue("MockHttpServletResponse", "Status", this.response.getStatus());
-		assertValue("MockHttpServletResponse", "Error message", response.getErrorMessage());
-		assertValue("MockHttpServletResponse", "Headers", headers);
-		assertValue("MockHttpServletResponse", "Content type", this.response.getContentType());
-		assertValue("MockHttpServletResponse", "Body", this.response.getContentAsString());
-		assertValue("MockHttpServletResponse", "Forwarded URL", this.response.getForwardedUrl());
-		assertValue("MockHttpServletResponse", "Redirected URL", this.response.getRedirectedUrl());
+		String heading = "MockHttpServletResponse";
+		assertValue(heading, "Status", this.response.getStatus());
+		assertValue(heading, "Error message", response.getErrorMessage());
+		assertValue(heading, "Headers", headers);
+		assertValue(heading, "Content type", this.response.getContentType());
+		assertValue(heading, "Body", this.response.getContentAsString());
+		assertValue(heading, "Forwarded URL", this.response.getForwardedUrl());
+		assertValue(heading, "Redirected URL", this.response.getRedirectedUrl());
+
+		Map<String, Map<String, Object>> printedValues = this.handler.getPrinter().printedValues;
+		String[] cookies = (String[]) printedValues.get(heading).get("Cookies");
+		assertEquals(2, cookies.length);
+		String cookie1 = cookies[0];
+		String cookie2 = cookies[1];
+		assertTrue(cookie1.startsWith("[" + Cookie.class.getSimpleName()));
+		assertTrue(cookie1.contains("name = 'cookie', value = 'cookieValue'"));
+		assertTrue(cookie1.endsWith("]"));
+		assertTrue(cookie2.startsWith("[" + Cookie.class.getSimpleName()));
+		assertTrue(cookie2.contains("name = 'enigma', value = '42', comment = 'This is a comment', domain = '.example.com', maxAge = 1234, path = '/crumbs', secure = true, version = 0, httpOnly = true"));
+		assertTrue(cookie2.endsWith("]"));
 	}
 
 	@Test
-	public void testPrintHandlerNull() throws Exception {
+	public void printHandlerNull() throws Exception {
 		StubMvcResult mvcResult = new StubMvcResult(this.request, null, null, null, null, null, this.response);
 		this.handler.handle(mvcResult);
 
 		assertValue("Handler", "Type", null);
 	}
 
 	@Test
-	public void testPrintHandler() throws Exception {
+	public void printHandler() throws Exception {
 		this.mvcResult.setHandler(new Object());
 		this.handler.handle(this.mvcResult);
 
 		assertValue("Handler", "Type", Object.class.getName());
 	}
 
 	@Test
-	public void testPrintHandlerMethod() throws Exception {
+	public void printHandlerMethod() throws Exception {
 		HandlerMethod handlerMethod = new HandlerMethod(this, "handle");
 		this.mvcResult.setHandler(handlerMethod);
 		this.handler.handle(mvcResult);
@@ -143,22 +159,22 @@ public void testPrintHandlerMethod() throws Exception {
 	}
 
 	@Test
-	public void testResolvedExceptionNull() throws Exception {
+	public void resolvedExceptionNull() throws Exception {
 		this.handler.handle(this.mvcResult);
 
 		assertValue("Resolved Exception", "Type", null);
 	}
 
 	@Test
-	public void testResolvedException() throws Exception {
+	public void resolvedException() throws Exception {
 		this.mvcResult.setResolvedException(new Exception());
 		this.handler.handle(this.mvcResult);
 
 		assertValue("Resolved Exception", "Type", Exception.class.getName());
 	}
 
 	@Test
-	public void testModelAndViewNull() throws Exception {
+	public void modelAndViewNull() throws Exception {
 		this.handler.handle(this.mvcResult);
 
 		assertValue("ModelAndView", "View name", null);
@@ -167,7 +183,7 @@ public void testModelAndViewNull() throws Exception {
 	}
 
 	@Test
-	public void testModelAndView() throws Exception {
+	public void modelAndView() throws Exception {
 		BindException bindException = new BindException(new Object(), "target");
 		bindException.reject("errorCode");
 
@@ -186,14 +202,14 @@ public void testModelAndView() throws Exception {
 	}
 
 	@Test
-	public void testFlashMapNull() throws Exception {
+	public void flashMapNull() throws Exception {
 		this.handler.handle(mvcResult);
 
 		assertValue("FlashMap", "Type", null);
 	}
 
 	@Test
-	public void testFlashMap() throws Exception {
+	public void flashMap() throws Exception {
 		FlashMap flashMap = new FlashMap();
 		flashMap.put("attrName", "attrValue");
 		this.request.setAttribute(DispatcherServlet.class.getName() + ".OUTPUT_FLASH_MAP", flashMap);

spring-test/src/test/java/org/springframework/test/web/servlet/samples/standalone/resulthandlers/PrintingResultHandlerTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2015 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,9 @@
 
 package org.springframework.test.web.servlet.samples.standalone.resulthandlers;
 
+import javax.servlet.http.Cookie;
+import javax.servlet.http.HttpServletResponse;
+
 import org.junit.Ignore;
 import org.junit.Test;
 
@@ -47,7 +50,8 @@ private static class SimpleController {
 
 		@RequestMapping("/")
 		@ResponseBody
-		public String hello() {
+		public String hello(HttpServletResponse response) {
+			response.addCookie(new Cookie("enigma", "42"));
 			return "Hello world";
 		}
 	}