On Fri, 29 Nov 2024 07:25:23 GMT, Jan Lahoda <jlah...@openjdk.org> wrote:
>> Currently, running `java` without any parameters will lead to an output that >> is a full `--help`, which is over 100 lines (on my computer at least), and >> it feels overwhelming. And many people might actually want to run >> JShell/REPL, not the `java` executable, but it is difficult find out about >> JShell. >> >> The proposal herein is to print a much shorter help, together with a pointer >> to JShell, when the executable does not know what to do. I.e. there is >> nothing specified to start, and no option like `--help` is specified. In >> particular, on my machine, it prints: >> >> Usage: java [java options...] <application> [application arguments...] >> >> Where <application> is one of: >> <mainclass> to execute the main method of a compiled main >> class >> -jar <jarfile>.jar to execute the main class of a JAR archive >> -m <module>[/<mainclass>] to execute the main class of a module >> <sourcefile>.java to compile and execute a source-file program >> >> Where key java options include: >> --class-path <class path> >> where <class path> is a list of directories and JAR archives to search >> for class files, separated by ":" >> --module-path <module path> >> where <module path> is a list of directories and JAR archives to search >> for modules, separated by ":" >> -version >> to print product version to the error stream and exit >> >> For additional help on usage: java --help >> For an interactive Java environment: jshell >> >> >> The full `java -help` with these changes is as follows: >> >> Usage: java [options] <mainclass> [args...] >> (to execute a class) >> or java [options] -jar <jarfile>.jar [args...] >> (to execute a jar file) >> or java [options] -m <module>[/<mainclass>] [args...] >> java [options] --module <module>[/<mainclass>] [args...] >> (to execute the main class in a module) >> or java [options] <sourcefile>.java [args] >> (to execute a source-file program) >> >> Arguments following the main class, source file, -jar <jarfile>.jar, >> -m or --module <module>/<mainclass> are passed as the arguments to >> main class. >> >> where options include: >> >> -cp <class search path of directories and zip/jar files> >> -classpath <class search path of directories and zip/jar files> >> --class-path <class search path of directories and zip/jar files> >> A ":"-separated list of directories, JAR archives, >> and ZIP archives to s... > > Jan Lahoda has updated the pull request incrementally with two additional > commits since the last revision: > > - Dropping printing of the version. > - Dropping the version from the concise help I think this looks okay, it doesn't preclude us changing it in the future or add the version in the concise or full usage in the future. ------------- Marked as reviewed by alanb (Reviewer). PR Review: https://git.openjdk.org/jdk/pull/21411#pullrequestreview-2470342068
