Merge branch '2.2.x' into 2.3.x

Closes gh-23671

Author: wilkinsona

spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/mock/web/SpringBootMockServletContext.java

@@ -20,6 +20,7 @@
 import java.io.IOException;
 import java.net.MalformedURLException;
 import java.net.URL;
+import java.nio.file.Files;
 
 import org.springframework.core.io.FileSystemResourceLoader;
 import org.springframework.core.io.Resource;
@@ -93,9 +94,7 @@ public URL getResource(String path) throws MalformedURLException {
 			try {
 				if (this.emptyRootDirectory == null) {
 					synchronized (this) {
-						File tempDirectory = File.createTempFile("spr", "servlet");
-						tempDirectory.delete();
-						tempDirectory.mkdirs();
+						File tempDirectory = Files.createTempDirectory("spr-servlet").toFile();
 						tempDirectory.deleteOnExit();
 						this.emptyRootDirectory = tempDirectory;
 					}

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/server/AbstractConfigurableWebServerFactory.java

@@ -19,6 +19,7 @@
 import java.io.File;
 import java.io.IOException;
 import java.net.InetAddress;
+import java.nio.file.Files;
 import java.util.Arrays;
 import java.util.LinkedHashSet;
 import java.util.Set;
@@ -185,9 +186,7 @@ public Shutdown getShutdown() {
 	 */
 	protected final File createTempDir(String prefix) {
 		try {
-			File tempDir = File.createTempFile(prefix + ".", "." + getPort());
-			tempDir.delete();
-			tempDir.mkdir();
+			File tempDir = Files.createTempDirectory(prefix + "." + getPort() + ".").toFile();
 			tempDir.deleteOnExit();
 			return tempDir;
 		}