How do I compile a .java with support for older versions of Java?

Question

I want to compile my .java\'s (several) into one .jar that are compatible with at least Java 1.6 and newer, preferably Java 1.5 and ne

Answer 1

You can specify the target version of the compiler lower than the build java version (all answers basically said that) but you should not: it is quite messy as it only works if you also supply the class libraries for the actual target version. If you do that you are much better off with simply using this old Java version to compile. Much cleaner and less stuff to setup. For Java 9 the options are a bit nicer but you still need an old JDK lying around for the rt.jar.

What you can do is in your ide and dedvelopment cycle use the -target/-bootclasspath trick to get faster compiler and better warnings, but IT and release builds then should be done with the target version.