Prefer servlet to reactive when Jersey and WebFlux are both available

Closes gh-13521

spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/context/SpringBootTestContextBootstrapper.java

@@ -86,6 +86,8 @@ public class SpringBootTestContextBootstrapper extends DefaultTestContextBootstr
 	private static final String MVC_WEB_ENVIRONMENT_CLASS = "org.springframework."
 			+ "web.servlet.DispatcherServlet";
 
+	private static final String JERSEY_WEB_ENVIRONMENT_CLASS = "org.glassfish.jersey.server.ResourceConfig";
+
 	private static final String ACTIVATE_SERVLET_LISTENER = "org.springframework.test."
 			+ "context.web.ServletTestExecutionListener.activateListener";
 
@@ -192,7 +194,8 @@ public class SpringBootTestContextBootstrapper extends DefaultTestContextBootstr
 
 	private WebApplicationType deduceWebApplicationType() {
 		if (ClassUtils.isPresent(REACTIVE_WEB_ENVIRONMENT_CLASS, null)
-				&& !ClassUtils.isPresent(MVC_WEB_ENVIRONMENT_CLASS, null)) {
+				&& !ClassUtils.isPresent(MVC_WEB_ENVIRONMENT_CLASS, null)
+				&& !ClassUtils.isPresent(JERSEY_WEB_ENVIRONMENT_CLASS, null)) {
 			return WebApplicationType.REACTIVE;
 		}
 		for (String className : WEB_ENVIRONMENT_CLASSES) {

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/SpringApplication.java

@@ -183,6 +183,8 @@ public class SpringApplication {
 	private static final String MVC_WEB_ENVIRONMENT_CLASS = "org.springframework."
 			+ "web.servlet.DispatcherServlet";
 
+	private static final String JERSEY_WEB_ENVIRONMENT_CLASS = "org.glassfish.jersey.server.ResourceConfig";
+
 	/**
 	 * Default banner location.
 	 */
@@ -271,7 +273,8 @@ public class SpringApplication {
 
 	private WebApplicationType deduceWebApplicationType() {
 		if (ClassUtils.isPresent(REACTIVE_WEB_ENVIRONMENT_CLASS, null)
-				&& !ClassUtils.isPresent(MVC_WEB_ENVIRONMENT_CLASS, null)) {
+				&& !ClassUtils.isPresent(MVC_WEB_ENVIRONMENT_CLASS, null)
+				&& !ClassUtils.isPresent(JERSEY_WEB_ENVIRONMENT_CLASS, null)) {
 			return WebApplicationType.REACTIVE;
 		}
 		for (String className : WEB_ENVIRONMENT_CLASSES) {