Polish "Allow Jetty's ThreadPool to be customized" (gh-5324)

spring-boot/src/main/java/org/springframework/boot/context/embedded/jetty/JettyEmbeddedServletContainerFactory.java

@@ -913,8 +913,7 @@ public class JettyEmbeddedServletContainerFactory
 
 		@Override
 		public Server createServer(ThreadPool threadPool) {
-			Server server = new Server(threadPool);
+			return new Server(threadPool);
-			return server;
 		}
 
 	}

spring-boot/src/test/java/org/springframework/boot/context/embedded/jetty/JettyEmbeddedServletContainerFactoryTests.java

@@ -259,26 +259,23 @@ public class JettyEmbeddedServletContainerFactoryTests
 	}
 
 	@Test
-	public void threadPool() throws Exception {
+	public void defaultThreadPool() throws Exception {
 		JettyEmbeddedServletContainerFactory factory = getFactory();
-
+		factory.setThreadPool(null);
-		ThreadPool threadPool = mock(ThreadPool.class);
+		assertThat(factory.getThreadPool()).isNull();
-		factory.setThreadPool(threadPool);
+		JettyEmbeddedServletContainer servletContainer = (JettyEmbeddedServletContainer) factory
-
+				.getEmbeddedServletContainer();
-		JettyEmbeddedServletContainer servletContainer = (JettyEmbeddedServletContainer) factory.getEmbeddedServletContainer();
+		assertThat(servletContainer.getServer().getThreadPool()).isNotNull();
-		assertThat(servletContainer.getServer().getThreadPool()).isSameAs(threadPool);
 	}
 
 	@Test
-	public void nullThreadPool() throws Exception {
+	public void customThreadPool() throws Exception {
 		JettyEmbeddedServletContainerFactory factory = getFactory();
-
+		ThreadPool threadPool = mock(ThreadPool.class);
-		factory.setThreadPool(null);
+		factory.setThreadPool(threadPool);
-
+		JettyEmbeddedServletContainer servletContainer = (JettyEmbeddedServletContainer) factory
-		assertThat(factory.getThreadPool()).isNull();
+				.getEmbeddedServletContainer();
-
+		assertThat(servletContainer.getServer().getThreadPool()).isSameAs(threadPool);
-		JettyEmbeddedServletContainer servletContainer = (JettyEmbeddedServletContainer) factory.getEmbeddedServletContainer();
-		assertThat(servletContainer.getServer().getThreadPool()).isNotNull();
 	}
 
 	@Override