compile with java 1.6 or lower about spoon

[GerardPaligot]

Hi @boeserwolf91,

Unfortunately, there is a reason for using java 1.7 and not a lower version. We would like that Spoon supports java 1.7 (and in a near future java 1.8) and there is already a minimum support for java 1.7 in Spoon.

So we can't compile Spoon in 1.6 or 1.5. Thanks for you question but sorry for the answer. :)

[pschichtel]

How is spoon's supported jdk version related to the jdk version it's build with?

[GerardPaligot]

If I am not mistaken I believe the minimum support for Java 1.7 is in the JDT compiler (integrate in Spoon) and this compiler has need a JVM 1.7 to compile the project.

[swolf91]

Before I switched to spoon I used the jdt compiler with Java 1.5. But it was an older version.
I'll have a look for the minimum jdk version tonight. But I don't think that one needs the jdk 7 to use Eclipse.

[swolf91]

@GerardPaligot The ecj dependency version 4.2.2 has a min jdk version of java 1.2 ! and the newest versions 4.4 needs at least java 1.6.

[GerardPaligot]

Good to know! Thanks for you search @boeserwolf91.

For now, ecj dependency is in version 4.2.2 in Spoon (and so compatible java 1.2) but Spoon use massively concepts of Java 1.5.

Do you have tested to compile in Java 1.5 and execute all tests?

[pschichtel]

Going below 1.5 would be crazy as you'd lose generics. As the current version of ecj requires jdk1.6 I'd go for that. You'd need to replace diamonds and try-with-resources and maybe nio2 API usage if you use it. I think that was all I saw when I tried to compile spoon against 1.6 and 1.5

[GerardPaligot]

Well yes, I also tested and the majority of errors are about the diamond operator. This seems not a big deal to solve these errors but, @pschichtel, I don't see any try-with-resources errors neither nio2 API usage.

[swolf91]

Great. So we can port it to compile with jdk 1.6 😄
I just had a short look into this. I found diamonds and the AutoCloseable API was used.
I think we can port it with a few commits.
Also it's possible to use a different jdk version for the tests. So the sources can compile with 1.6 and the tests with 1.8 to test lambdas and co (well they're not supported yet, I just want to let you know that it works)