Foo.java

import java.io.FileReader;
import java.io.File;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.FileNotFoundException;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.Queue;

public class Foo {
  public static void main(String args[]) throws FileNotFoundException {
    LinkedBlockingQueue<String> queue = new LinkedBlockingQueue<String>();
    int count = 0;

    Popper<String> thread = new Popper<String>(queue);
    thread.start();
    BufferedReader reader = new BufferedReader(new FileReader(new File(args[0])));
    try {
      String line;
      while ((line = reader.readLine()) != null ) {
        queue.add(line);
        count += 1;
      }
      System.out.println(count);
    } catch (IOException e) {
      // nothing, we break
    }
    thread.interrupt();
  }

}

Popper.java

import java.util.Queue;
import java.util.concurrent.LinkedBlockingQueue;

public class Popper<T> extends Thread {
  private LinkedBlockingQueue<T> queue;
  public Popper(LinkedBlockingQueue<T> queue) {
    this.queue = queue;
  }
  public void run() {
    while (true) {
      try {
        this.queue.take();
      } catch (InterruptedException e) {
        break;
      }
    }
  }
}

read.rb

# Use buftok because `File#each_line` is slower by about 30%.
require "buftok"

TERMINATE = :terminate

2.times do
  start = Time.now
  queue = Queue.new

  file = File.new(ARGV[0])

  thread = Thread.new(queue) do |queue|
    count = 0
    while queue.pop != TERMINATE
      count += 1
    end
    puts count
  end

  tok = BufferedTokenizer.new("\n")
  size = 1<<15
  while true
    data = file.read(size)
    break unless data
    tok.extract(data).each do |line|
      event = { "message" => line }
      queue << event
    end
  end

  queue << TERMINATE
  thread.join

  duration = Time.now - start
  puts duration
end

RUNS.txt

% rvm 1.7.24 do ruby read.rb ~/sample-logs-2gb
10499965
11.8
10499965
10.747

% java Foo ~/sample-logs-2gb
10499965
Duration: 8.552