Add Java 14 to JavaVersion enumeration

See gh-19511

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/system/JavaVersion.java

 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,7 @@
 
 package org.springframework.boot.system;
 
+import java.lang.invoke.MethodHandles;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
@@ -60,7 +61,11 @@ public enum JavaVersion {
 	/**
 	 * Java 13.
 	 */
-	THIRTEEN("13", String.class, "stripIndent");
+	THIRTEEN("13", String.class, "stripIndent"),
+	/**
+	 * Java 14.
+	 */
+	FOURTEEN("14", MethodHandles.Lookup.class, "hasFullPrivilegeAccess");
 
 	private final String name;
 

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/system/JavaVersionTests.java

 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -115,4 +115,10 @@ class JavaVersionTests {
 		assertThat(JavaVersion.getJavaVersion()).isEqualTo(JavaVersion.THIRTEEN);
 	}
 
+	@Test
+	@EnabledOnJre(JRE.JAVA_14)
+	void currentJavaVersionFourteen() {
+		assertThat(JavaVersion.getJavaVersion()).isEqualTo(JavaVersion.FOURTEEN);
+	}
+
 }