InstantFormatter accepts RFC-1123 values as well

Issue: SPR-14201

spring-context/src/main/java/org/springframework/format/datetime/standard/InstantFormatter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -18,6 +18,7 @@ package org.springframework.format.datetime.standard;
 
 import java.text.ParseException;
 import java.time.Instant;
+import java.time.format.DateTimeFormatter;
 import java.util.Locale;
 
 import org.springframework.format.Formatter;
@@ -26,19 +27,30 @@ import org.springframework.lang.UsesJava8;
 /**
  * {@link Formatter} implementation for a JSR-310 {@link java.time.Instant},
  * following JSR-310's parsing rules for an Instant (that is, not using a
- * configurable {@link java.time.format.DateTimeFormatter}).
+ * configurable {@link java.time.format.DateTimeFormatter}): accepting the
+ * default {@code ISO_INSTANT} format as well as {@code RFC_1123_DATE_TIME}
+ * (which is commonly used for HTTP date header values), as of Spring 4.3.
  *
  * @author Juergen Hoeller
  * @since 4.0
  * @see java.time.Instant#parse
+ * @see java.time.format.DateTimeFormatter#ISO_INSTANT
+ * @see java.time.format.DateTimeFormatter#RFC_1123_DATE_TIME
  */
 @UsesJava8
 public class InstantFormatter implements Formatter<Instant> {
 
 	@Override
 	public Instant parse(String text, Locale locale) throws ParseException {
+		if (text.length() > 0 && Character.isDigit(text.charAt(0))) {
+			// assuming UTC instant a la "2007-12-03T10:15:30.00Z"
 			return Instant.parse(text);
 		}
+		else {
+			// assuming RFC-1123 value a la "Tue, 3 Jun 2008 11:05:30 GMT"
+			return Instant.from(DateTimeFormatter.RFC_1123_DATE_TIME.parse(text));
+		}
+	}
 
 	@Override
 	public String print(Instant object, Locale locale) {

spring-web/src/test/java/org/springframework/web/method/annotation/RequestHeaderMethodArgumentResolverTests.java

@@ -17,6 +17,9 @@
 package org.springframework.web.method.annotation;
 
 import java.lang.reflect.Method;
+import java.time.Instant;
+import java.time.format.DateTimeFormatter;
+import java.util.Date;
 import java.util.Map;
 
 import org.junit.After;
@@ -25,11 +28,14 @@ import org.junit.Test;
 
 import org.springframework.core.MethodParameter;
 import org.springframework.core.annotation.SynthesizingMethodParameter;
+import org.springframework.format.support.DefaultFormattingConversionService;
 import org.springframework.mock.web.test.MockHttpServletRequest;
 import org.springframework.mock.web.test.MockHttpServletResponse;
 import org.springframework.util.ReflectionUtils;
 import org.springframework.web.bind.ServletRequestBindingException;
 import org.springframework.web.bind.annotation.RequestHeader;
+import org.springframework.web.bind.support.ConfigurableWebBindingInitializer;
+import org.springframework.web.bind.support.DefaultDataBinderFactory;
 import org.springframework.web.context.request.NativeWebRequest;
 import org.springframework.web.context.request.RequestContextHolder;
 import org.springframework.web.context.request.ServletWebRequest;
@@ -54,6 +60,8 @@ public class RequestHeaderMethodArgumentResolverTests {
 	private MethodParameter paramResolvedNameWithExpression;
 	private MethodParameter paramResolvedNameWithPlaceholder;
 	private MethodParameter paramNamedValueMap;
+	private MethodParameter paramDate;
+	private MethodParameter paramInstant;
 
 	private MockHttpServletRequest servletRequest;
 
@@ -75,6 +83,8 @@ public class RequestHeaderMethodArgumentResolverTests {
 		paramResolvedNameWithExpression = new SynthesizingMethodParameter(method, 4);
 		paramResolvedNameWithPlaceholder = new SynthesizingMethodParameter(method, 5);
 		paramNamedValueMap = new SynthesizingMethodParameter(method, 6);
+		paramDate = new SynthesizingMethodParameter(method, 7);
+		paramInstant = new SynthesizingMethodParameter(method, 8);
 
 		servletRequest = new MockHttpServletRequest();
 		webRequest = new ServletWebRequest(servletRequest, new MockHttpServletResponse());
@@ -103,7 +113,7 @@ public class RequestHeaderMethodArgumentResolverTests {
 
 		Object result = resolver.resolveArgument(paramNamedDefaultValueStringHeader, null, webRequest, null);
 		assertTrue(result instanceof String);
-		assertEquals("Invalid result", expected, result);
+		assertEquals(expected, result);
 	}
 
 	@Test
@@ -113,14 +123,14 @@ public class RequestHeaderMethodArgumentResolverTests {
 
 		Object result = resolver.resolveArgument(paramNamedValueStringArray, null, webRequest, null);
 		assertTrue(result instanceof String[]);
-		assertArrayEquals("Invalid result", expected, (String[]) result);
+		assertArrayEquals(expected, (String[]) result);
 	}
 
 	@Test
 	public void resolveDefaultValue() throws Exception {
 		Object result = resolver.resolveArgument(paramNamedDefaultValueStringHeader, null, webRequest, null);
 		assertTrue(result instanceof String);
-		assertEquals("Invalid result", "bar", result);
+		assertEquals("bar", result);
 	}
 
 	@Test
@@ -145,7 +155,7 @@ public class RequestHeaderMethodArgumentResolverTests {
 		try {
 			Object result = resolver.resolveArgument(paramResolvedNameWithExpression, null, webRequest, null);
 			assertTrue(result instanceof String);
-			assertEquals("Invalid result", expected, result);
+			assertEquals(expected, result);
 		}
 		finally {
 			System.clearProperty("systemProperty");
@@ -161,7 +171,7 @@ public class RequestHeaderMethodArgumentResolverTests {
 		try {
 			Object result = resolver.resolveArgument(paramResolvedNameWithPlaceholder, null, webRequest, null);
 			assertTrue(result instanceof String);
-			assertEquals("Invalid result", expected, result);
+			assertEquals(expected, result);
 		}
 		finally {
 			System.clearProperty("systemProperty");
@@ -182,6 +192,34 @@ public class RequestHeaderMethodArgumentResolverTests {
 		resolver.resolveArgument(paramNamedValueStringArray, null, webRequest, null);
 	}
 
+	@Test
+	public void dateConversion() throws Exception {
+		String rfc1123val = "Thu, 21 Apr 2016 17:11:08 +0100";
+		servletRequest.addHeader("name", rfc1123val);
+
+		ConfigurableWebBindingInitializer bindingInitializer = new ConfigurableWebBindingInitializer();
+		bindingInitializer.setConversionService(new DefaultFormattingConversionService());
+		Object result = resolver.resolveArgument(paramDate, null, webRequest,
+				new DefaultDataBinderFactory(bindingInitializer));
+
+		assertTrue(result instanceof Date);
+		assertEquals(new Date(rfc1123val), result);
+	}
+
+	@Test
+	public void instantConversion() throws Exception {
+		String rfc1123val = "Thu, 21 Apr 2016 17:11:08 +0100";
+		servletRequest.addHeader("name", rfc1123val);
+
+		ConfigurableWebBindingInitializer bindingInitializer = new ConfigurableWebBindingInitializer();
+		bindingInitializer.setConversionService(new DefaultFormattingConversionService());
+		Object result = resolver.resolveArgument(paramInstant, null, webRequest,
+				new DefaultDataBinderFactory(bindingInitializer));
+
+		assertTrue(result instanceof Instant);
+		assertEquals(Instant.from(DateTimeFormatter.RFC_1123_DATE_TIME.parse(rfc1123val)), result);
+	}
+
 
 	public void params(
 			@RequestHeader(name = "name", defaultValue = "bar") String param1,
@@ -190,7 +228,9 @@ public class RequestHeaderMethodArgumentResolverTests {
 			@RequestHeader(name = "name", defaultValue="#{request.contextPath}") String param4,
 			@RequestHeader("#{systemProperties.systemProperty}") String param5,
 			@RequestHeader("${systemProperty}") String param6,
-			@RequestHeader("name") Map<?, ?> unsupported) {
+			@RequestHeader("name") Map<?, ?> unsupported,
+			@RequestHeader("name") Date dateParam,
+			@RequestHeader("name") Instant instantParam) {
 	}
 
 }