I also used junit as a semi-REPL similar to how you describe. then I started playing with a REPL for a fully dynaimic language and when I came back to java, there were parts that I missed.
I would say the things it does that the typical junit run does not are:
1. Explorative queries, send sql statements see the results quickly. What particularly helps here is that any collection is converted to a table with each column representing a getXXX method.
2. Command line instant queries. Sometimes I just want an advanced calculator on the command line. I do "jpad -e 2+2" and it returns 4. No messing around with IDEs.
3. Automatic smart guessing of imports and ability to upload results straight to website to share with colleagues.
That's what I liked, so I built it in. The lack of traffic may suggest others did not find it as useful :)
So I actually created a java REPL: http://jpad.io
I would say the things it does that the typical junit run does not are:
1. Explorative queries, send sql statements see the results quickly. What particularly helps here is that any collection is converted to a table with each column representing a getXXX method.
2. Command line instant queries. Sometimes I just want an advanced calculator on the command line. I do "jpad -e 2+2" and it returns 4. No messing around with IDEs.
3. Automatic smart guessing of imports and ability to upload results straight to website to share with colleagues.
That's what I liked, so I built it in. The lack of traffic may suggest others did not find it as useful :)