killjava

#!/usr/bin/env ruby
require 'optparse'

# Parse arguments
OPTIONS = {}
op = OptionParser.new do |x|
  x.banner = 'killjava [-9] [-n] [java_main_class]'
  x.separator ''

  x.on("-9", "--KILL", "Send KILL signal instead of TERM") do
    OPTIONS[:kill] = true
  end

  x.on("-n", "--no-prompt", "Do not prompt user, kill all matching processes") do
    OPTIONS[:no_prompt] = true
  end

  x.on("-h", "--help", "Show this message") do
    puts op
    exit
  end
end
op.parse!(ARGV)
OPTIONS[:main_class] = ARGV.first

# Figure out terminal characteristics
lines, columns = `stty size`.split.map { |x| x.to_i } rescue [25, 80]

# Obtain list of java processes
processes = `jps -lv`.split("\n")

# Print/filter process ids
pids = []
i = 0
processes.each do |p|
  main = p.split(" ")[1]
  if !OPTIONS[:main_class] || main[OPTIONS[:main_class]]
    pids << p.split(" ")[0].to_i
    command = p.split(" ").drop(1).join(" ")
    puts "#{i}: #{command[0..columns-7]}"  # display 1-line per process
    i += 1
  end
end

if pids.size == 0 && OPTIONS[:main_class]
  puts "No matching processes"
  exit
end

if pids.size == 0
  puts "No Java processes"
  exit
end

def kill(pid)
  cmd = ["kill"]
  cmd << "-9" if OPTIONS[:kill]
  cmd << pid
  cmd = cmd.join(" ")
  puts cmd
  `#{cmd}`
end

def invalid()
  puts "Invalid process"
  exit
end

if OPTIONS[:no_prompt]
  # Kill all matching processes
  pids.each { |pid| kill(pid) }
else
  puts "Kill which java process?"
  pid = STDIN.gets
  if pid && pid.chomp != ""
    pid = Integer(pid) rescue invalid
    invalid if (pid < 0) || (pid >= pids.size)
    kill(pids[pid])
  end
end