Re: Java completion for Java files

[Michal Politowski <mpol@xxxxxxx>]

Dnia Mon,  5 Feb 2024 21:47:48 -0500, Henri Tremblay napisał(a):
> Yes.
> Let's say you have a file in a directory:
> "src/main/java/org/zsh/Main.java". The class is named Main and is in the
> package org.zsh in this case.
> If you compile it with "javac src/main/java/org/zsh/Main.java" it will
> generate a file named "src/main/java/org/zsh/Main.class".
> 
> So, if you execute it the old way, you would do "java -cp src/main/java
> org.zsh.Main" which means "Please execute the class with a main() method
> that is called Main and found in the package org.zsh. The classpath where
> this class can be found is "src/main".
> 
> If you execute it the new way, you don't need to compile with javac. So you
> only have "src/main/java/org/zsh/Main.java".
> And you will execute by doing "java src/main/java/org/zsh/Main.java" and
> that's it.
> 
> Bottom line, indeed, the ".java" at the end tells that it's a java source
> file and not a compile class found in the classpath that you want to
> execute.

Not exactly. You can have a class named java on the classpath.

The precise behaviour as specified here https://openjdk.org/jeps/330#Description
(since Java 11) seems to be: if the first non-option argument is
- a name of an existing file with .java extension, or
- a name of an existing file and the --source <version> option is given
then compile/run the source.

> On Mon, 5 Feb 2024 at 15:44, Bart Schaefer <schaefer@xxxxxxxxxxxxxxxx>
> wrote:
> 
> > On Mon, Feb 5, 2024 at 10:04 AM Henri Tremblay <henri.tremblay@xxxxxxxxx>
> > wrote:
> > >
> > > Java now supports (since Java 10 I think) command lines like
> > >
> > > java Math.java
> > >
> > > It will then just compile and launch that java file. But zsh won't
> > autocomplete for that. It only wants a jar, class file or whatever.
> >
> > The issue is here in the _arguments setup for _java:
> >
> >     '(-):class:_java_class -m main ${(kv)opt_args[(i)(-classpath|-cp)]}' \
> >     '*::args:= _normal' \
> >      && return 0
> >
> > The (-) says that the first word after "java" must either be an option
> > (start with "-") or must be a class name.  The completion stops there
> > unless working on the next word.
> >
> > How does "java" itself distinguish between a class name and a file
> > name?  Just whether the string ends in ".java"?
> >

-- 
Michał Politowski
Talking has been known to lead to communication if practiced carelessly.