1 files changed, 182 insertions, 56 deletions

diff --git a/spring-web/src/main/java/org/springframework/http/HttpHeaders.java b/spring-web/src/main/java/org/springframework/http/HttpHeaders.java
index 1170bb06..0ba9a02a 100644
--- a/spring-web/src/main/java/org/springframework/http/HttpHeaders.java
+++ b/spring-web/src/main/java/org/springframework/http/HttpHeaders.java
@@ -34,6 +34,8 @@ import java.util.Locale;
 import java.util.Map;
 import java.util.Set;
 import java.util.TimeZone;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 import org.springframework.util.Assert;
 import org.springframework.util.LinkedCaseInsensitiveMap;
@@ -55,6 +57,8 @@ import org.springframework.util.StringUtils;
  *
  * @author Arjen Poutsma
  * @author Sebastien Deleuze
+ * @author Brian Clozel
+ * @author Juergen Hoeller
  * @since 3.0
  */
 public class HttpHeaders implements MultiValueMap<String, String>, Serializable {
@@ -372,6 +376,12 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 			"EEE MMM dd HH:mm:ss yyyy"
 	};
 
+	/**
+	 * Pattern matching ETag multiple field values in headers such as "If-Match", "If-None-Match"
+	 * @see <a href="https://tools.ietf.org/html/rfc7232#section-2.3">Section 2.3 of RFC 7232</a>
+	 */
+	private static final Pattern ETAG_HEADER_VALUE_PATTERN = Pattern.compile("\\*|\\s*((W\\/)?(\"[^\"]*\"))\\s*,?");
+
 	private static TimeZone GMT = TimeZone.getTimeZone("GMT");
 
 
@@ -419,19 +429,7 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	 * <p>Returns an empty list when the acceptable media types are unspecified.
 	 */
 	public List<MediaType> getAccept() {
-		String value = getFirst(ACCEPT);
-		List<MediaType> result = (value != null ? MediaType.parseMediaTypes(value) : Collections.<MediaType>emptyList());
-
-		// Some containers parse 'Accept' into multiple values
-		if (result.size() == 1) {
-			List<String> acceptHeader = get(ACCEPT);
-			if (acceptHeader.size() > 1) {
-				value = StringUtils.collectionToCommaDelimitedString(acceptHeader);
-				result = MediaType.parseMediaTypes(value);
-			}
-		}
-
-		return result;
+		return MediaType.parseMediaTypes(get(ACCEPT));
 	}
 
 	/**
@@ -442,10 +440,10 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	}
 
 	/**
-	 * Returns the value of the {@code Access-Control-Allow-Credentials} response header.
+	 * Return the value of the {@code Access-Control-Allow-Credentials} response header.
 	 */
 	public boolean getAccessControlAllowCredentials() {
-		return new Boolean(getFirst(ACCESS_CONTROL_ALLOW_CREDENTIALS));
+		return Boolean.parseBoolean(getFirst(ACCESS_CONTROL_ALLOW_CREDENTIALS));
 	}
 
 	/**
@@ -456,10 +454,10 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	}
 
 	/**
-	 * Returns the value of the {@code Access-Control-Allow-Headers} response header.
+	 * Return the value of the {@code Access-Control-Allow-Headers} response header.
 	 */
 	public List<String> getAccessControlAllowHeaders() {
-		return getFirstValueAsList(ACCESS_CONTROL_ALLOW_HEADERS);
+		return getValuesAsList(ACCESS_CONTROL_ALLOW_HEADERS);
 	}
 
 	/**
@@ -476,7 +474,7 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 		List<HttpMethod> result = new ArrayList<HttpMethod>();
 		String value = getFirst(ACCESS_CONTROL_ALLOW_METHODS);
 		if (value != null) {
-			String[] tokens = value.split(",\\s*");
+			String[] tokens = StringUtils.tokenizeToStringArray(value, ",", true, true);
 			for (String token : tokens) {
 				HttpMethod resolved = HttpMethod.resolve(token);
 				if (resolved != null) {
@@ -498,7 +496,7 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	 * Return the value of the {@code Access-Control-Allow-Origin} response header.
 	 */
 	public String getAccessControlAllowOrigin() {
-		return getFirst(ACCESS_CONTROL_ALLOW_ORIGIN);
+		return getFieldValues(ACCESS_CONTROL_ALLOW_ORIGIN);
 	}
 
 	/**
@@ -509,10 +507,10 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	}
 
 	/**
-	 * Returns the value of the {@code Access-Control-Expose-Headers} response header.
+	 * Return the value of the {@code Access-Control-Expose-Headers} response header.
 	 */
 	public List<String> getAccessControlExposeHeaders() {
-		return getFirstValueAsList(ACCESS_CONTROL_EXPOSE_HEADERS);
+		return getValuesAsList(ACCESS_CONTROL_EXPOSE_HEADERS);
 	}
 
 	/**
@@ -523,7 +521,7 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	}
 
 	/**
-	 * Returns the value of the {@code Access-Control-Max-Age} response header.
+	 * Return the value of the {@code Access-Control-Max-Age} response header.
 	 * <p>Returns -1 when the max age is unknown.
 	 */
 	public long getAccessControlMaxAge() {
@@ -539,10 +537,10 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	}
 
 	/**
-	 * Returns the value of the {@code Access-Control-Request-Headers} request header.
+	 * Return the value of the {@code Access-Control-Request-Headers} request header.
 	 */
 	public List<String> getAccessControlRequestHeaders() {
-		return getFirstValueAsList(ACCESS_CONTROL_REQUEST_HEADERS);
+		return getValuesAsList(ACCESS_CONTROL_REQUEST_HEADERS);
 	}
 
 	/**
@@ -643,7 +641,7 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	 * Return the value of the {@code Cache-Control} header.
 	 */
 	public String getCacheControl() {
-		return getFirst(CACHE_CONTROL);
+		return getFieldValues(CACHE_CONTROL);
 	}
 
 	/**
@@ -664,7 +662,7 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	 * Return the value of the {@code Connection} header.
 	 */
 	public List<String> getConnection() {
-		return getFirstValueAsList(CONNECTION);
+		return getValuesAsList(CONNECTION);
 	}
 
 	/**
@@ -783,6 +781,30 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	}
 
 	/**
+	 * Set the (new) value of the {@code If-Match} header.
+	 * @since 4.3
+	 */
+	public void setIfMatch(String ifMatch) {
+		set(IF_MATCH, ifMatch);
+	}
+
+	/**
+	 * Set the (new) value of the {@code If-Match} header.
+	 * @since 4.3
+	 */
+	public void setIfMatch(List<String> ifMatchList) {
+		set(IF_MATCH, toCommaDelimitedString(ifMatchList));
+	}
+
+	/**
+	 * Return the value of the {@code If-Match} header.
+	 * @since 4.3
+	 */
+	public List<String> getIfMatch() {
+		return getETagValuesAsList(IF_MATCH);
+	}
+
+	/**
 	 * Set the (new) value of the {@code If-Modified-Since} header.
 	 * <p>The date should be specified as the number of milliseconds since
 	 * January 1, 1970 GMT.
@@ -814,35 +836,31 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 		set(IF_NONE_MATCH, toCommaDelimitedString(ifNoneMatchList));
 	}
 
-	protected String toCommaDelimitedString(List<String> list) {
-		StringBuilder builder = new StringBuilder();
-		for (Iterator<String> iterator = list.iterator(); iterator.hasNext();) {
-			String ifNoneMatch = iterator.next();
-			builder.append(ifNoneMatch);
-			if (iterator.hasNext()) {
-				builder.append(", ");
-			}
-		}
-		return builder.toString();
-	}
-
 	/**
 	 * Return the value of the {@code If-None-Match} header.
 	 */
 	public List<String> getIfNoneMatch() {
-		return getFirstValueAsList(IF_NONE_MATCH);
+		return getETagValuesAsList(IF_NONE_MATCH);
 	}
 
-	protected List<String> getFirstValueAsList(String header) {
-		List<String> result = new ArrayList<String>();
-		String value = getFirst(header);
-		if (value != null) {
-			String[] tokens = value.split(",\\s*");
-			for (String token : tokens) {
-				result.add(token);
-			}
-		}
-		return result;
+	/**
+	 * Set the (new) value of the {@code If-Unmodified-Since} header.
+	 * <p>The date should be specified as the number of milliseconds since
+	 * January 1, 1970 GMT.
+	 * @since 4.3
+	 */
+	public void setIfUnmodifiedSince(long ifUnmodifiedSince) {
+		setDate(IF_UNMODIFIED_SINCE, ifUnmodifiedSince);
+	}
+
+	/**
+	 * Return the value of the {@code If-Unmodified-Since} header.
+	 * <p>The date is returned as the number of milliseconds since
+	 * January 1, 1970 GMT. Returns -1 when the date is unknown.
+	 * @since 4.3
+	 */
+	public long getIfUnmodifiedSince() {
+		return getFirstDate(IF_UNMODIFIED_SINCE, false);
 	}
 
 	/**
@@ -943,11 +961,43 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	}
 
 	/**
+	 * Set the request header names (e.g. "Accept-Language") for which the
+	 * response is subject to content negotiation and variances based on the
+	 * value of those request headers.
+	 * @param requestHeaders the request header names
+	 * @since 4.3
+	 */
+	public void setVary(List<String> requestHeaders) {
+		set(VARY, toCommaDelimitedString(requestHeaders));
+	}
+
+	/**
+	 * Return the request header names subject to content negotiation.
+	 * @since 4.3
+	 */
+	public List<String> getVary() {
+		return getValuesAsList(VARY);
+	}
+
+	/**
+	 * Set the given date under the given header name after formatting it as a string
+	 * using the pattern {@code "EEE, dd MMM yyyy HH:mm:ss zzz"}. The equivalent of
+	 * {@link #set(String, String)} but for date headers.
+	 * @since 3.2.4
+	 */
+	public void setDate(String headerName, long date) {
+		SimpleDateFormat dateFormat = new SimpleDateFormat(DATE_FORMATS[0], Locale.US);
+		dateFormat.setTimeZone(GMT);
+		set(headerName, dateFormat.format(new Date(date)));
+	}
+
+	/**
 	 * Parse the first header value for the given header name as a date,
 	 * return -1 if there is no value, or raise {@link IllegalArgumentException}
 	 * if the value cannot be parsed as a date.
 	 * @param headerName the header name
 	 * @return the parsed date header, or -1 if none
+	 * @since 3.2.4
 	 */
 	public long getFirstDate(String headerName) {
 		return getFirstDate(headerName, true);
@@ -992,16 +1042,92 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	}
 
 	/**
-	 * Set the given date under the given header name after formatting it as a string
-	 * using the pattern {@code "EEE, dd MMM yyyy HH:mm:ss zzz"}. The equivalent of
-	 * {@link #set(String, String)} but for date headers.
+	 * Return all values of a given header name,
+	 * even if this header is set multiple times.
+	 * @param headerName the header name
+	 * @return all associated values
+	 * @since 4.3
+	 */
+	public List<String> getValuesAsList(String headerName) {
+		List<String> values = get(headerName);
+		if (values != null) {
+			List<String> result = new ArrayList<String>();
+			for (String value : values) {
+				if (value != null) {
+					String[] tokens = StringUtils.tokenizeToStringArray(value, ",");
+					for (String token : tokens) {
+						result.add(token);
+					}
+				}
+			}
+			return result;
+		}
+		return Collections.emptyList();
+	}
+
+	/**
+	 * Retrieve a combined result from the field values of the ETag header.
+	 * @param headerName the header name
+	 * @return the combined result
+	 * @since 4.3
+	 */
+	protected List<String> getETagValuesAsList(String headerName) {
+		List<String> values = get(headerName);
+		if (values != null) {
+			List<String> result = new ArrayList<String>();
+			for (String value : values) {
+				if (value != null) {
+					Matcher matcher = ETAG_HEADER_VALUE_PATTERN.matcher(value);
+					while (matcher.find()) {
+						if ("*".equals(matcher.group())) {
+							result.add(matcher.group());
+						}
+						else {
+							result.add(matcher.group(1));
+						}
+					}
+					if (result.isEmpty()) {
+						throw new IllegalArgumentException(
+								"Could not parse header '" + headerName + "' with value '" + value + "'");
+					}
+				}
+			}
+			return result;
+		}
+		return Collections.emptyList();
+	}
+
+	/**
+	 * Retrieve a combined result from the field values of multi-valued headers.
+	 * @param headerName the header name
+	 * @return the combined result
+	 * @since 4.3
 	 */
-	public void setDate(String headerName, long date) {
-		SimpleDateFormat dateFormat = new SimpleDateFormat(DATE_FORMATS[0], Locale.US);
-		dateFormat.setTimeZone(GMT);
-		set(headerName, dateFormat.format(new Date(date)));
+	protected String getFieldValues(String headerName) {
+		List<String> headerValues = get(headerName);
+		return (headerValues != null ? toCommaDelimitedString(headerValues) : null);
+	}
+
+	/**
+	 * Turn the given list of header values into a comma-delimited result.
+	 * @param headerValues the list of header values
+	 * @return a combined result with comma delimitation
+	 */
+	protected String toCommaDelimitedString(List<String> headerValues) {
+		StringBuilder builder = new StringBuilder();
+		for (Iterator<String> it = headerValues.iterator(); it.hasNext(); ) {
+			String val = it.next();
+			builder.append(val);
+			if (it.hasNext()) {
+				builder.append(", ");
+			}
+		}
+		return builder.toString();
 	}
 
+
+	// MultiValueMap implementation
+
 	/**
 	 * Return the first header value for the given header name, if any.
 	 * @param headerName the header name