# assume $src contains a whole file of java code...

# first, split $src code into an array, on "/* ... */" style comments,
# making sure to keep these comments as array elements

my @chunks = split m{ (/\* .*? \*/) }sx, $src;

# now go through the chunks, and look for uncommented "public" methods

my $mod;  # this will be the output string

for ( @chunks ) {
    if ( m{^/\*} ) {  # this is a "/*...*/" comment
        $mod .= $_;   # so just copy it to output
    }
    else {
        my @lines = split /[\r\n]+/;
        for ( @lines ) {
            if ( m{^\s*public\s+\w+} ) {
                # this line looks like a public declaration
                # so do something special with it
            }
            $mod .= $_;  # copy line to output
        }
    }
}

print $mod;