Add extra attributes to Link and use for HAL mediatype

src/main/java/org/springframework/hateoas/Link.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -15,6 +15,13 @@
  */
 package org.springframework.hateoas;
 
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.experimental.Wither;
+
 import java.io.Serializable;
 import java.util.Collections;
 import java.util.HashMap;
@@ -37,9 +44,14 @@
  * Value object for links.
  * 
  * @author Oliver Gierke
+ * @author Greg Turnquist
  */
 @XmlType(name = "link", namespace = Link.ATOM_NAMESPACE)
 @JsonIgnoreProperties("templated")
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@AllArgsConstructor(access = AccessLevel.PACKAGE)
+@Getter
+@EqualsAndHashCode(of = {"rel", "href", "hreflang", "media", "title", "deprecation"})
 public class Link implements Serializable {
 
 	private static final long serialVersionUID = -9037755944661782121L;
@@ -53,8 +65,13 @@ public class Link implements Serializable {
 	public static final String REL_NEXT = "next";
 	public static final String REL_LAST = "last";
 
-	@XmlAttribute private String rel;
-	@XmlAttribute private String href;
+	@XmlAttribute @Wither private String rel;
+	@XmlAttribute @Wither private String href;
+	@XmlAttribute @Wither private String hreflang;
+	@XmlAttribute @Wither private String media;
+	@XmlAttribute @Wither private String title;
+	@XmlAttribute @Wither private String type;
+	@XmlAttribute @Wither private String deprecation;
 	@XmlTransient @JsonIgnore private UriTemplate template;
 
 	/**
@@ -85,49 +102,14 @@ public Link(String href, String rel) {
 	 */
 	public Link(UriTemplate template, String rel) {
 
-		Assert.notNull(template, "UriTempalte must not be null!");
+		Assert.notNull(template, "UriTemplate must not be null!");
 		Assert.hasText(rel, "Rel must not be null or empty!");
 
 		this.template = template;
 		this.href = template.toString();
 		this.rel = rel;
 	}
 
-	/**
-	 * Empty constructor required by the marshalling framework.
-	 */
-	protected Link() {
-
-	}
-
-	/**
-	 * Returns the actual URI the link is pointing to.
-	 * 
-	 * @return
-	 */
-	public String getHref() {
-		return href;
-	}
-
-	/**
-	 * Returns the rel of the link.
-	 * 
-	 * @return
-	 */
-	public String getRel() {
-		return rel;
-	}
-
-	/**
-	 * Returns a {@link Link} pointing to the same URI but with the given relation.
-	 * 
-	 * @param rel must not be {@literal null} or empty.
-	 * @return
-	 */
-	public Link withRel(String rel) {
-		return new Link(href, rel);
-	}
-
 	/**
 	 * Returns a {@link Link} pointing to the same URI but with the {@code self} relation.
 	 * 
@@ -195,46 +177,35 @@ private UriTemplate getUriTemplate() {
 		return template;
 	}
 
-	/* 
+	/*
 	 * (non-Javadoc)
-	 * @see java.lang.Object#equals(java.lang.Object)
+	 * @see java.lang.Object#toString()
 	 */
 	@Override
-	public boolean equals(Object obj) {
+	public String toString() {
+		String linkString = String.format("<%s>;rel=\"%s\"", href, rel);
 
-		if (this == obj) {
-			return true;
+		if (hreflang != null) {
+			linkString += ";hreflang=\"" + hreflang + "\"";
 		}
 
-		if (!(obj instanceof Link)) {
-			return false;
+		if (media != null) {
+			linkString += ";media=\"" + media + "\"";
 		}
 
-		Link that = (Link) obj;
-
-		return this.href.equals(that.href) && this.rel.equals(that.rel);
-	}
-
-	/* 
-	 * (non-Javadoc)
-	 * @see java.lang.Object#hashCode()
-	 */
-	@Override
-	public int hashCode() {
+		if (title != null) {
+			linkString += ";title=\"" + title + "\"";
+		}
 
-		int result = 17;
-		result += 31 * href.hashCode();
-		result += 31 * rel.hashCode();
-		return result;
-	}
+		if (type != null) {
+			linkString += ";type=\"" + type + "\"";
+		}
 
-	/* 
-	 * (non-Javadoc)
-	 * @see java.lang.Object#toString()
-	 */
-	@Override
-	public String toString() {
-		return String.format("<%s>;rel=\"%s\"", href, rel);
+		if (deprecation != null) {
+			linkString += ";deprecation=\"" + deprecation + "\"";
+		}
+
+		return linkString;
 	}
 
 	/**
@@ -263,7 +234,29 @@ public static Link valueOf(String element) {
 				throw new IllegalArgumentException("Link does not provide a rel attribute!");
 			}
 
-			return new Link(matcher.group(1), attributes.get("rel"));
+			Link link = new Link(matcher.group(1), attributes.get("rel"));
+
+			if (attributes.containsKey("hreflang")) {
+				link = link.withHreflang(attributes.get("hreflang"));
+			}
+
+			if (attributes.containsKey("media")) {
+				link = link.withMedia(attributes.get("media"));
+			}
+
+			if (attributes.containsKey("title")) {
+				link = link.withTitle(attributes.get("title"));
+			}
+
+			if (attributes.containsKey("type")) {
+				link = link.withType(attributes.get("type"));
+			}
+
+			if (attributes.containsKey("deprecation")) {
+				link = link.withDeprecation(attributes.get("deprecation"));
+			}
+
+			return link;
 
 		} else {
 			throw new IllegalArgumentException(String.format("Given link header %s is not RFC5988 compliant!", element));
@@ -283,7 +276,7 @@ private static Map<String, String> getAttributeMap(String source) {
 		}
 
 		Map<String, String> attributes = new HashMap<String, String>();
-		Pattern keyAndValue = Pattern.compile("(\\w+)=\"(\\p{Lower}[\\p{Lower}\\p{Digit}\\.\\-]*|" + URI_PATTERN + ")\"");
+		Pattern keyAndValue = Pattern.compile("(\\w+)=\"(\\p{Lower}[\\p{Lower}\\p{Digit}\\.\\-\\s]*|" + URI_PATTERN + ")\"");
 		Matcher matcher = keyAndValue.matcher(source);
 
 		while (matcher.find()) {

src/main/java/org/springframework/hateoas/Links.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2016 the original author or authors.
+ * Copyright 2013-2017 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.
@@ -29,10 +29,11 @@
  * Value object to represent a list of {@link Link}s.
  * 
  * @author Oliver Gierke
+ * @author Greg Turnquist
  */
 public class Links implements Iterable<Link> {
 
-	private static final Pattern LINK_HEADER_PATTERN = Pattern.compile("(<[^>]*>;rel=\"[^\"]*\")");
+	private static final Pattern LINK_HEADER_PATTERN = Pattern.compile("(<[^>]*>(;\\w+=\"[^\"]*\")+)");
 
 	static final Links NO_LINKS = new Links(Collections.<Link> emptyList());
 

src/main/java/org/springframework/hateoas/hal/LinkMixin.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2014 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -28,13 +28,46 @@
  * 
  * @author Alexander Baetz
  * @author Oliver Gierke
+ * @author Greg Turnquist
  */
-@JsonIgnoreProperties(value = "rel")
+@JsonIgnoreProperties({"rel", "media"})
 abstract class LinkMixin extends Link {
 
 	private static final long serialVersionUID = 4720588561299667409L;
 
-	/* 
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.hateoas.Link#getHreflang()
+	 */
+	@Override
+	@JsonInclude(Include.NON_NULL)
+	public abstract String getHreflang();
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.hateoas.Link#getTitle()
+	 */
+	@Override
+	@JsonInclude(Include.NON_NULL)
+	public abstract String getTitle();
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.hateoas.Link#getType()
+	 */
+	@Override
+	@JsonInclude(Include.NON_NULL)
+	public abstract String getType();
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.hateoas.Link#getDeprecation()
+	 */
+	@Override
+	@JsonInclude(Include.NON_NULL)
+	public abstract String getDeprecation();
+
+	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.hateoas.Link#isTemplate()
 	 */

src/test/java/org/springframework/hateoas/AbstractJackson2MarshallingIntegrationTest.java

@@ -1,17 +1,34 @@
+/*
+ * Copyright 2012-2017 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 package org.springframework.hateoas;
 
 import java.io.StringWriter;
 import java.io.Writer;
 
 import org.junit.Before;
 
+import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.databind.ObjectMapper;
 
 /**
  * Base class to test objects against the Jackson 2.0 {@link ObjectMapper}.
  * 
  * @author Oliver Gierke
  * @author Jon Brisbin
+ * @author Greg Turnquist
  */
 public abstract class AbstractJackson2MarshallingIntegrationTest {
 
@@ -20,6 +37,7 @@ public abstract class AbstractJackson2MarshallingIntegrationTest {
 	@Before
 	public void setUp() {
 		mapper = new ObjectMapper();
+		mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
 	}
 
 	protected String write(Object object) throws Exception {

src/test/java/org/springframework/hateoas/LinkUnitTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -28,6 +28,7 @@
  * Unit tests for {@link Link}.
  * 
  * @author Oliver Gierke
+ * @author Greg Turnquist
  */
 public class LinkUnitTest {
 
@@ -103,21 +104,46 @@ public void returnsNullForNullOrEmptyLink() {
 		assertThat(Link.valueOf(""), is(nullValue()));
 	}
 
+	/**
+	 * @see #54
+	 * @see #100
+	 */
 	@Test
 	public void parsesRFC5988HeaderIntoLink() {
 
 		assertThat(Link.valueOf("</something>;rel=\"foo\""), is(new Link("/something", "foo")));
 		assertThat(Link.valueOf("</something>;rel=\"foo\";title=\"Some title\""), is(new Link("/something", "foo")));
+		assertThat(Link.valueOf("</customer/1>;rel=\"self\";hreflang=\"en\";media=\"pdf\";title=\"pdf customer copy\";type=\"portable document\";deprecation=\"http://example.com/customers/deprecated\""),
+			is(new Link("/customer/1")
+				.withHreflang("en")
+				.withMedia("pdf")
+				.withTitle("pdf customer copy")
+				.withType("portable document")
+				.withDeprecation("http://example.com/customers/deprecated")));
+	}
+
+	/**
+	 * @see #100
+	 */
+	@Test
+	public void ignoresUnrecognizedAttributes() {
+		Link link = Link.valueOf("</something>;rel=\"foo\";unknown=\"should fail\"");
+
+		assertThat(link.getHref(), is("/something"));
+		assertThat(link.getRel(), is("foo"));
 	}
 
 	@Test(expected = IllegalArgumentException.class)
 	public void rejectsMissingRelAttribute() {
-		Link.valueOf("</something>);title=\"title\"");
+		Link.valueOf("</something>;title=\"title\"");
 	}
 
 	@Test(expected = IllegalArgumentException.class)
 	public void rejectsLinkWithoutAttributesAtAll() {
-		Link.valueOf("</something>);title=\"title\"");
+
+		Link link = Link.valueOf("</something>");
+
+		System.out.println(link);
 	}
 
 	@Test(expected = IllegalArgumentException.class)