Logstash - require at file:/opt/logstash/vendor/jar/jruby-complete-1.7.11.jar

After installation of logstash 1.4.2 rpm on CentOS, I got stuck across this error:

[root@psj admin]# tail -f /var/log/logstash/logstash.err
  require at file:/opt/logstash/vendor/jar/jruby-complete-1.7.11.jar!/META-INF/jruby.home/lib/ruby/shared/rubygems/core_ext/kernel_require.rb:55
  require at org/jruby/RubyKernel.java:1085
   (root) at file:/opt/logstash/vendor/jar/jruby-complete-1.7.11.jar!/META-INF/jruby.home/lib/ruby/shared/ffi.rb:1
   (root) at file:/opt/logstash/vendor/jar/jruby-complete-1.7.11.jar!/META-INF/jruby.home/lib/ruby/shared/rubygems/core_ext/kernel_require.rb:1
  require at file:/opt/logstash/vendor/jar/jruby-complete-1.7.11.jar!/META-INF/jruby.home/lib/ruby/shared/rubygems/core_ext/kernel_require.rb:55
  require at org/jruby/RubyKernel.java:1085
     LibC at /opt/logstash/lib/logstash/util/prctl.rb:4
   (root) at /opt/logstash/lib/logstash/util/prctl.rb:3
     main at /opt/logstash/lib/logstash/runner.rb:79
   (root) at /opt/logstash/lib/logstash/runner.rb:215
^C

[root@psj admin]# service logstash status
logstash is not running


After some time, I realized that it may be a path issue  or not getting proper java environment variables issue.
So, to get rid of this, please check your environment for JAVA paths:

[root@psj ELK]# cat /etc/environment
JRE_HOME=/usr/java/jre1.8.0_40/
JAVA_HOME=/usr/java/jdk1.8.0_31
JDK_HOME=/usr/java/jdk1.8.0_31/
[root@psj ELK]# source /etc/environment

Also, add logstash and java to the path:

[root@psj ELK]# export PATH=$PATH:/usr/java/default/bin
[root@psj ELK]# export PATH=/opt/logstash/bin:$PATH

[root@psj ELK]# service logstash status
logstash is running
If this is not your case, perhaps, you can look up bug details reported on github.
https://github.com/elastic/logstash/issues/1289