Java11: Run Java code in a single file as is

Java 11 has been released.

The official version of Java 11 has been released, and support for the Oracle JDK will be charged from this version. Expectations for free long-term support provided by OpenJDK are low at this time

"Execute Java code in a single file as it is" in it

JEP 330: Launch Single-File Source-Code Programs

I tried.


I tried the Windows version. ~~ I followed the link from ~~, but ... I followed the link to the Oracle JDK and installed it. ~~ ~~ OpenJDK 11 is here (look for later). ~~

You can download it from the following.

Install it for the time being and check the java version. I updated from java 8 on Windows The environment variables remained unchanged at java 8, so I manually rewrote the PATH and JAVA_HOME paths to java 11.

$ java -version
openjdk version "11" 2018-09-25
OpenJDK Runtime Environment 18.9 (build 11+28)
OpenJDK 64-Bit Server VM 18.9 (build 11+28, mixed mode)

Run Java code in a single file as is

And a single java file

class Test {
    public static void main(String[] arg) {
        System.out.println("Hello World");

Run without compiling

$ java
Hello World

I was able to execute it. ..

Of course you can compile and run

$ javac
$ ls
$ java Test
Hello World

Obviously, When using .class files, there is no first intermediate compilation, so execution is faster.

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