Added instructions

Author: blafond

tooling/jbang/README.md

@@ -0,0 +1,25 @@
+Rapid Reactive testing with JBang
+
+If you want to see them in action, here's how it works:
+
+1. [Download JBang](https://www.jbang.dev/download)
+2. Start the default Postgres we use for testing (you can replace podman with docker):
+    ```
+    podman run --rm --name HibernateTestingPGSQL \
+    -e POSTGRES_USER=hreact -e POSTGRES_PASSWORD=hreact -e POSTGRES_DB=hreact \
+    -p 5432:5432 postgres:13.2
+    ```
+3. JBang it:
+    ```
+    jbang https://github.com/hibernate/hibernate-reactive/tree/main/tooling/jbang/Example.java
+    ```
+   or
+    ```
+    jbang https://github.com/hibernate/hibernate-reactive/tree/main/tooling/jbang/SampleIssueTest.java
+    ```
+4. (Optional) If you want to edit the class with Idea
+    ```
+    jbang edit --open=idea https://github.com/hibernate/hibernate-reactive/tree/main/tooling/jbang/SampleIssueTest.java
+    ```
+
+_NOTE: For testing with other DB's see [podman.md](https://github.com/hibernate/hibernate-reactive/blob/main/podman.md)_.