Merge branch '2.2.x'

Closes gh-20957

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/undertow/UndertowCompressionConfigurer.java

@@ -32,6 +32,7 @@ import io.undertow.util.HttpString;
 
 import org.springframework.boot.web.server.Compression;
 import org.springframework.http.HttpHeaders;
+import org.springframework.util.InvalidMimeTypeException;
 import org.springframework.util.MimeType;
 import org.springframework.util.MimeTypeUtils;
 
@@ -90,11 +91,17 @@ final class UndertowCompressionConfigurer {
 		public boolean resolve(HttpServerExchange value) {
 			String contentType = value.getResponseHeaders().getFirst(HttpHeaders.CONTENT_TYPE);
 			if (contentType != null) {
-				for (MimeType mimeType : this.mimeTypes) {
-					if (mimeType.isCompatibleWith(MimeTypeUtils.parseMimeType(contentType))) {
-						return true;
+				try {
+					MimeType parsed = MimeTypeUtils.parseMimeType(contentType);
+					for (MimeType mimeType : this.mimeTypes) {
+						if (mimeType.isCompatibleWith(parsed)) {
+							return true;
+						}
 					}
 				}
+				catch (InvalidMimeTypeException ex) {
+					return false;
+				}
 			}
 			return false;
 		}

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/reactive/server/AbstractReactiveWebServerFactoryTests.java

@@ -447,10 +447,12 @@ public abstract class AbstractReactiveWebServerFactoryTests {
 	}
 
 	protected void assertResponseIsCompressed(ResponseEntity<Void> response) {
+		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(response.getHeaders().getFirst("X-Test-Compressed")).isEqualTo("true");
 	}
 
 	protected void assertResponseIsNotCompressed(ResponseEntity<Void> response) {
+		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(response.getHeaders().keySet()).doesNotContain("X-Test-Compressed");
 	}