regex - Match pattern in a file ruby -

i want search string in file (mostly .txt file) , return true if there match. i've tried multiple solutions such follows:

# 1. file.foreach('c:\installlist.txt').grep /java/  # 2. file.open("c:/installlist.txt") |f|   f.each_line |line|     if line =~ '/java/'       puts "found java: #{line}"     else       puts "not found"     end   end end 

but none of these seem work. please seems trivial thing, still not happening.

# 3.  file.each_line('c:/installlist.txt') |li|   puts li if (li[/java/]) end 

here snippet of installlist.txt file.

swmsm 12.0.0.1
microsoft office live meeting 2007 8.0.6362.190
microsoft .net framework 4.5 4.5.50709
google update helper 1.3.24.15
vagrant 1.6.1
windows azure storage tools - v2.2.2 2.2.2.0
microsoft visual c++ 2005 redistributable 8.0.61001
aws command line interface 1.3.17
microsoft visual c++ 2008 redistributable - x86 9.0.30729.4148 9.0.30729.4148
microsoft silverlight 5.1.30214.0
oracle vm virtualbox 4.3.10 4.3.10
java auto updater 2.1.9.5
rapidboot shield 1.23

you read entire file string:

if file.read('file.txt') =~ /java/   # ... end 

or process line line:

if file.foreach('file.txt').any? { |line| line =~ /java/ }   # ... end 

in case you're dealing file encoding other ascii / utf-8, have specify when opening file. open utf-16 file bom you'd use:

file.read('file.txt', mode: 'r:bom|utf-16:utf-8')