Add JavaVersion entry for JDK 16

See gh-24453

Author: dreis2211

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

@@ -21,6 +21,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
+import java.util.stream.Stream;
 
 import org.springframework.util.ClassUtils;
 
@@ -71,7 +72,12 @@ public enum JavaVersion {
 	/**
 	 * Java 15.
 	 */
-	FIFTEEN("15", CharSequence.class, "isEmpty");
+	FIFTEEN("15", CharSequence.class, "isEmpty"),
+
+	/**
+	 * Java 16.
+	 */
+	SIXTEEN("16", Stream.class, "toList");
 
 	private final String name;
 

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

@@ -127,4 +127,10 @@ void currentJavaVersionFifteen() {
 		assertThat(JavaVersion.getJavaVersion()).isEqualTo(JavaVersion.FIFTEEN);
 	}
 
+	@Test
+	@EnabledOnJre(JRE.JAVA_16)
+	void currentJavaVersionSixteen() {
+		assertThat(JavaVersion.getJavaVersion()).isEqualTo(JavaVersion.SIXTEEN);
+	}
+
 }