diff --git a/jaxrs-tck/src/main/java/ee/jakarta/tck/ws/rs/jaxrs31/ee/multipart/MultipartSupportIT.java b/jaxrs-tck/src/main/java/ee/jakarta/tck/ws/rs/jaxrs31/ee/multipart/MultipartSupportIT.java
index 2029a8d9..46c12e81 100644
--- a/jaxrs-tck/src/main/java/ee/jakarta/tck/ws/rs/jaxrs31/ee/multipart/MultipartSupportIT.java
+++ b/jaxrs-tck/src/main/java/ee/jakarta/tck/ws/rs/jaxrs31/ee/multipart/MultipartSupportIT.java
@@ -29,6 +29,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.function.Supplier;
 
 import jakarta.ws.rs.ApplicationPath;
 import jakarta.ws.rs.Consumes;
@@ -136,7 +137,7 @@ public void basicTest() throws Exception {
                             .request(MediaType.MULTIPART_FORM_DATA_TYPE)
                             .post(Entity.entity(new GenericEntity<>(multipart) {
                             }, MediaType.MULTIPART_FORM_DATA))) {
-                Assertions.assertEquals(Response.Status.OK, response.getStatusInfo());
+                Assertions.assertEquals(200, response.getStatus());
                 final List<EntityPart> entityParts = response.readEntity(new GenericType<>() {
                 });
                 if (entityParts.size() != 3) {
@@ -151,8 +152,23 @@ public void basicTest() throws Exception {
                 Assertions.assertNotNull(part, getMessage(entityParts));
                 Assertions.assertEquals("test string", part.getContent(String.class));
 
+                // The javadoc for EntityPart.getContent(Class<T> type) states:
+                // "Subsequent invocations will result in an {@code IllegalStateException}. 
+                // Likewise this method will throw an {@code IllegalStateException} if it is 
+                // called after calling {@link #getContent} or {@link #getContent(GenericType)}.
+                try {
+                    part.getContent(String.class);
+                    Assertions.fail("IllegalStateException is expected when getContent() is " +
+                            "invoked more than once.");
+                } catch (IllegalStateException e) {
+                    // expected exception
+                } catch (Throwable t) {
+                    Assertions.fail("Incorrect Throwable received: " + t);
+                }
+                
                 part = find(entityParts, "received-file");
                 Assertions.assertNotNull(part, getMessage(entityParts));
+                Assertions.assertEquals("test file", part.getFileName().get());
                 Assertions.assertTrue(part.getContent(String.class).contains("value6"));
 
                 part = find(entityParts, "added-input-stream");
@@ -187,11 +203,11 @@ public void singleFormParamTest() throws Exception {
                             .mediaType(MediaType.TEXT_PLAIN_TYPE)
                             .build());
             try (
-                    Response response = client.target(createCombinedUri(uri, "test//single-form-param"))
+                    Response response = client.target(createCombinedUri(uri, "test/single-form-param"))
                             .request(MediaType.MULTIPART_FORM_DATA_TYPE)
                             .post(Entity.entity(new GenericEntity<>(multipart) {
                             }, MediaType.MULTIPART_FORM_DATA))) {
-                Assertions.assertEquals(Response.Status.OK, response.getStatusInfo());
+                Assertions.assertEquals(200, response.getStatus());
                 final List<EntityPart> entityParts = response.readEntity(new GenericType<>() {
                 });
                 if (entityParts.size() != 3) {
@@ -240,7 +256,7 @@ public void multiFormParamTest() throws Exception {
                             .request(MediaType.MULTIPART_FORM_DATA_TYPE)
                             .post(Entity.entity(new GenericEntity<>(multipart) {
                             }, MediaType.MULTIPART_FORM_DATA))) {
-                Assertions.assertEquals(Response.Status.OK, response.getStatusInfo());
+                Assertions.assertEquals(200, response.getStatus());
                 final List<EntityPart> entityParts = response.readEntity(new GenericType<>() {
                 });
                 if (entityParts.size() != 3) {
@@ -266,30 +282,36 @@ private static void verifyEntityPart(final List<EntityPart> parts, final String
         Assertions.assertEquals(text, part.getContent(String.class));
     }
 
-    private static String getMessage(final List<EntityPart> parts) throws IOException {
-        final StringBuilder msg = new StringBuilder();
-        final Iterator<EntityPart> iter = parts.iterator();
-        while (iter.hasNext()) {
-            final EntityPart part = iter.next();
-            msg.append('[')
-                   .append(part.getName())
-                   .append("={")
-                   .append("headers=")
-                   .append(part.getHeaders())
-                   .append(", mediaType=")
-                   .append(part.getMediaType())
-                   .append(", body=")
-                   .append(toString(part.getContent()))
-                   .append('}');
-            if (iter.hasNext()) {
-                msg.append("], ");
-            } else {
-                msg.append(']');
+    private static Supplier<String> getMessage(final List<EntityPart> parts) {
+        return () -> {
+            final StringBuilder msg = new StringBuilder();
+            final Iterator<EntityPart> iter = parts.iterator();
+            while (iter.hasNext()) {
+                final EntityPart part = iter.next();
+                try {
+                    msg.append('[')
+                            .append(part.getName())
+                            .append("={")
+                            .append("headers=")
+                            .append(part.getHeaders())
+                            .append(", mediaType=")
+                            .append(part.getMediaType())
+                            .append(", body=")
+                            .append(toString(part.getContent()))
+                            .append('}');
+                } catch (IOException e) {
+                    Assertions.fail("Unable to proces Entityparts." + e);                    
+                }
+                if (iter.hasNext()) {
+                    msg.append("], ");
+                } else {
+                    msg.append(']');
+                }
             }
-        }
-        return msg.toString();
+            return msg.toString();
+        };
     }
-
+    
     private static String toString(final InputStream in) throws IOException {
         // try-with-resources fails here due to a bug in the
         //noinspection TryFinallyCanBeTryWithResources
@@ -360,7 +382,7 @@ public Response basicTest(final List<EntityPart> parts) throws IOException {
                             .mediaType(MediaType.APPLICATION_OCTET_STREAM_TYPE)
                             .build(),
                     EntityPart.withName("received-file")
-                            .content(find(parts,"file"))
+                            .content(find(parts,"file").getFileName().get(),find(parts,"file").getContent())
                             .mediaType(MediaType.APPLICATION_XML)
                             .build(),
                     EntityPart.withName("added-input-stream")