Migrate Java 1.8 to 11+

This is a repo with some examples used in the Java Magazine article I wrote for Q1 2020.

It was set up as a Maven project but I tested the stuff with different docker containers with different java versions.

Prerequisites

• Docker

How to use

if you want to see the differences that happen when compiling with java 1.8 or e.g. java 9 or 11 the follow the instructions below.

git clone

Java 1.8

• Open a terminal and go to this repo

docker run --rm -it --name j8 -v "$(pwd):/project" ivonet/openjdk:8 /bin/bash

• on docker container prompt:

cd /project/src/main/java
javac nl/ivonet/CLASS_YOU_WANT_TO_COMPILE_HERE.java
java java nl.ivonet.CLASS_YOU_WANT_TO_COMPILE_HERE 

Java 9

• Open a terminal and go to this repo

docker run --rm -it --name j9 -v "$(pwd):/project" ivonet/openjdk:9 /bin/bash

• on docker container prompt:

cd /project/src/main/java
javac nl/ivonet/CLASS_YOU_WANT_TO_COMPILE_HERE.java
java java nl.ivonet.CLASS_YOU_WANT_TO_COMPILE_HERE # This will only work if the compile worked :-)

Java 11

• Open a terminal and go to this repo

docker run --rm -it --name j11 -v "$(pwd):/project" ivonet/openjdk:11 /bin/bash

• on docker container prompt:

cd /project/src/main/java
javac nl/ivonet/CLASS_YOU_WANT_TO_COMPILE_HERE.java
java java nl.ivonet.CLASS_YOU_WANT_TO_COMPILE_HERE # This will only work if the compile worked :-)