java-12

I am trying to build a project with JDK-12 ea. While trying to execute a sample class: public static void main(String[] args) { Scanner scanner = new Scanner(System.in); int value = scanner.nextInt(); // After JEP-325 switch (value) { case 1 ->System.out.println("one"); case 2 ->System.out.println("two"); default ->System.out.println("many"); } } The IDE throws the error that reads Error:java: error: invalid source release: 13 Relevant project configuration screens : Module settings SDKs Compiler settings About IDE: IntelliJ IDEA 2018.3.3 (Community Edition) Build #IC-183.5153.38, built on

I'm trying to migrate a project to Java 12, with --enable-preview . I added --enable-preview in compiler settings: <plugin> <artifactId>maven-compiler-plugin</artifactId> <version>3.8.0</version> <configuration> <release>12</release> <compilerArgs> <arg>--enable-preview</arg> </compilerArgs> </configuration> </plugin> And also added it in argLine for surefire and failsafe: <properties> <argLine>--enable-preview</argLine> </properties> And do a mvn clean verify results in: [ERROR] Failed to execute goal org.apache.maven.plugins:maven-surefire-plugin:3.0.0-M3:test (default-test) on project

I seem to stumble across something interesting in ArrayList implementation that I can't wrap my head around. Here is some code that shows what I mean: public class Sandbox { private static final VarHandle VAR_HANDLE_ARRAY_LIST; static { try { Lookup lookupArrayList = MethodHandles.privateLookupIn(ArrayList.class, MethodHandles.lookup()); VAR_HANDLE_ARRAY_LIST = lookupArrayList.findVarHandle(ArrayList.class, "elementData", Object[].class); } catch (Exception e) { e.printStackTrace(); throw new RuntimeException(); } } public static void main(String[] args) { List<String> defaultConstructorList =

With JDK/12 EarlyAccess Build 10 , the JEP-325 Switch Expressions has been integrated as a preview feature in the JDK. A sample code for the expressions (as in the JEP as well): Scanner scanner = new Scanner(System.in); Day day = Day.valueOf(scanner.next()); switch (day) { case MONDAY, TUESDAY -> System.out.println("Back to work.") ; case WEDNESDAY -> System.out.println("Wait for the end of week...") ; case THURSDAY,FRIDAY -> System.out.println("Plan for the weekend?"); case SATURDAY, SUNDAY -> System.out.println("Enjoy the holiday!"); } where Day being an enum as public enum Day { MONDAY,