#187, #188 - Fix header handling in Traverson.

Traverson correctly applies headers when using JsonPath to evaluate GET result: accepts the media types it is configured for and preserves additional headers.

src/main/java/org/springframework/hateoas/client/Traverson.java

@@ -56,6 +56,7 @@ import com.jayway.jsonpath.JsonPath;
  * 
  * @see https://github.com/basti1302/traverson
  * @author Oliver Gierke
+ * @author Dietrich Schulten
  * @since 0.11
  */
 public class Traverson {
@@ -226,7 +227,7 @@ public class Traverson {
 
 			Assert.hasText(jsonPath, "JSON path must not be null or empty!");
 
-			String forObject = template.getForObject(traverseToFinalUrl(), String.class);
+			String forObject = template.exchange(traverseToFinalUrl(), GET, prepareRequest(headers), String.class).getBody();
 			return JsonPath.read(forObject, jsonPath);
 		}
 
@@ -239,8 +240,7 @@ public class Traverson {
 		public <T> ResponseEntity<T> toEntity(Class<T> type) {
 
 			Assert.notNull(type, "Target type must not be null!");
-
-			return template.getForEntity(traverseToFinalUrl(), type);
+			return template.exchange(traverseToFinalUrl(), GET, prepareRequest(headers), type);
 		}
 
 		private String traverseToFinalUrl() {

src/test/java/org/springframework/hateoas/client/TraversonTests.java

@@ -29,6 +29,7 @@ import org.springframework.core.ParameterizedTypeReference;
 import org.springframework.hateoas.Link;
 import org.springframework.hateoas.MediaTypes;
 import org.springframework.hateoas.Resource;
+import org.springframework.http.HttpHeaders;
 import org.springframework.http.MediaType;
 
 /**
@@ -120,6 +121,44 @@ public class TraversonTests {
 		assertThat(result.getContent().name, is("Keanu Reaves"));
 	}
 
+	/**
+	 * @see #187
+	 */
+	@Test
+	public void sendsConfiguredHeadersForJsonPathExpression() {
+
+		String expectedHeader = "<http://www.example.com>;rel=\"home\"";
+
+		HttpHeaders headers = new HttpHeaders();
+		headers.add("Link", expectedHeader);
+
+		assertThat(traverson.follow("movies", "movie", "actor").//
+				withHeaders(headers).<String> toObject("$.name"), is("Keanu Reaves"));
+
+		verifyThatRequest(). //
+				havingPathEqualTo("/actors/d95dbf62-f900-4dfa-9de8-0fc71e02ffa4"). //
+				havingHeader("Link", hasItem(expectedHeader));
+	}
+
+	/**
+	 * @see #187
+	 */
+	@Test
+	public void sendsConfiguredHeadersForToEntity() {
+
+		String expectedHeader = "<http://www.example.com>;rel=\"home\"";
+
+		HttpHeaders headers = new HttpHeaders();
+		headers.add("Link", expectedHeader);
+
+		traverson.follow("movies", "movie", "actor").//
+				withHeaders(headers).toEntity(Actor.class);
+
+		verifyThatRequest(). //
+				havingPathEqualTo("/actors/d95dbf62-f900-4dfa-9de8-0fc71e02ffa4"). //
+				havingHeader("Link", hasItem(expectedHeader));
+	}
+
 	private void setUpActors() {
 
 		Resource<Actor> actor = new Resource<Actor>(new Actor("Keanu Reaves"));