Switch jdk versions (bash + perl)

switch-jdk.pl

#!/usr/bin/env perl
use v5.28;
use Data::Dumper;
use Tie::IxHash;

my @jdk_paths = qw{~/.jdks /usr/lib/jvm};

my @jdks;
push @jdks, glob "$_/*-*" for @jdk_paths;

my $version = $ARGV[0];
unless ($version) {
    say STDERR $_ for @jdks;
    exit 1
}

my @matches = grep { $_ =~ m{.*/*-\Q$version\E} }  @jdks;


if (@matches < 1) {
    say STDERR "No matching versions. Available:";
    say STDERR $_ for @jdks;
    exit 1
}

if (@matches > 1) {
    say STDERR  "Multiple matching versions found: ";
    say STDERR $_ for @matches;
    exit 1
}

my $jdk = $matches[0];
say STDERR "Using $jdk";

my $p = $ENV{PATH};

my @expanded_paths;
for my $path (@jdk_paths) {
    push @expanded_paths, $path;
    my $x = glob $path;
    push @expanded_paths, $x unless $x eq $path or !$x;
}

my $paths_rx = join '|', @expanded_paths;

my @v = grep ! m{/$paths_rx/}, split /[:]/, $p;

tie my %s, 'Tie::IxHash';
$s{$_}++ for @v;

say 'export PATH="' . $matches[0] . '/bin:' . join(':', keys %s) . '"';
say 'export JAVA_HOME=' . $matches[0];