DATACMNS-407 - Fixed sort parameter building in HateoasAwareSortHandlerMethodArgumentResolver.

We're now replacing the sort parameter for the URI to be created instead of simply appending them to the source URI to prevent previously applied sort parameters to be taken forward.

Author: odrotbohm

src/main/java/org/springframework/data/web/HateoasSortHandlerMethodArgumentResolver.java

@@ -26,14 +26,14 @@
 /**
  * Extension of {@link SortHandlerMethodArgumentResolver} that also supports enhancing URIs using Spring HATEOAS
  * support.
- *
+ * 
  * @since 1.6
  * @author Oliver Gierke
  * @author Thomas Darimont
  * @author Nick Williams
  */
-public class HateoasSortHandlerMethodArgumentResolver extends SortHandlerMethodArgumentResolver
-		implements UriComponentsContributor {
+public class HateoasSortHandlerMethodArgumentResolver extends SortHandlerMethodArgumentResolver implements
+		UriComponentsContributor {
 
 	/*
 	 * (non-Javadoc)
@@ -47,19 +47,22 @@ public void enhance(UriComponentsBuilder builder, MethodParameter parameter, Obj
 		}
 
 		Sort sort = (Sort) value;
+		String sortParameter = getSortParameter(parameter);
 
 		if (legacyMode) {
 
 			List<String> expressions = legacyFoldExpressions(sort);
 			Assert.isTrue(expressions.size() == 2,
 					String.format("Expected 2 sort expressions (fields, direction) but got %d!", expressions.size()));
-			builder.queryParam(getSortParameter(parameter), expressions.get(0));
-			builder.queryParam(getLegacyDirectionParameter(parameter), expressions.get(1));
+			builder.replaceQueryParam(sortParameter, expressions.get(0));
+			builder.replaceQueryParam(getLegacyDirectionParameter(parameter), expressions.get(1));
 
 		} else {
 
+			builder.replaceQueryParam(sortParameter);
+
 			for (String expression : foldIntoExpressions(sort)) {
-				builder.queryParam(getSortParameter(parameter), expression);
+				builder.queryParam(sortParameter, expression);
 			}
 		}
 	}

src/test/java/org/springframework/data/web/HateoasSortHandlerMethodArgumentResolverUnitTests.java

@@ -19,6 +19,8 @@
 import static org.junit.Assert.*;
 import static org.springframework.data.domain.Sort.Direction.*;
 
+import java.net.URI;
+
 import org.junit.Test;
 import org.springframework.core.MethodParameter;
 import org.springframework.data.domain.Sort;
@@ -32,7 +34,7 @@
 public class HateoasSortHandlerMethodArgumentResolverUnitTests extends SortHandlerMethodArgumentResolverUnitTests {
 
 	@Test
-	public void buildsUpRequestParameters() {
+	public void buildsUpRequestParameters() throws Exception {
 
 		assertUriStringFor(SORT, "sort=firstname,lastname,desc");
 		assertUriStringFor(new Sort(ASC, "foo").and(new Sort(DESC, "bar").and(new Sort(ASC, "foobar"))),
@@ -41,9 +43,21 @@ public void buildsUpRequestParameters() {
 				"sort=foo,bar,asc&sort=foobar,desc");
 	}
 
-	private void assertUriStringFor(Sort sort, String expected) {
+	/**
+	 * @see DATACMNS-407
+	 */
+	@Test
+	public void replacesExistingRequestParameters() throws Exception {
+		assertUriStringFor(SORT, "/?sort=firstname,lastname,desc", "/?sort=foo,asc");
+	}
+
+	private void assertUriStringFor(Sort sort, String expected) throws Exception {
+		assertUriStringFor(sort, expected, "/");
+	}
+
+	private void assertUriStringFor(Sort sort, String expected, String baseUri) throws Exception {
 
-		UriComponentsBuilder builder = UriComponentsBuilder.fromPath("/");
+		UriComponentsBuilder builder = UriComponentsBuilder.fromUri(new URI(baseUri));
 		MethodParameter parameter = getParameterOfMethod("supportedMethod");
 
 		new HateoasSortHandlerMethodArgumentResolver().enhance(builder, parameter, sort);