#!/usr/bin/perl
# get_lines.pl
use strict;
my $check_next_line = "no";
my ($new_line, $mp);
while (<>) {
    chomp;
    if (/^NEW/) {
        $new_line = $_;  # save the line beginning with word NEW
        $check_next_line = "yes";
        $mp = (split (/\s+/, $_))[2];  # save the field containing MP code
        next;
    }
    elsif (/^CNL/) {
        if ($mp eq (split (/\s+/, $_))[2]) {
            print $new_line, "\n";
            print;
            print "\n";
        }
    }
    $check_next_line = "no";
}

perl get_lines.pl new_file

awk '/^CNL/&&x=="NEW"$3&&$0=y RS$0
{x=$1$3;y=$0}' filename

import java.io.*;


public class GetLine {

	private String prevWord = "";
	private String prevLine = "";
	
	private void parse(String fileName){
		try {
	        BufferedReader in = new BufferedReader(new FileReader(fileName));
	        System.out.println("Reading file: " +fileName);
	        String line = "";
	        while ((line = in.readLine()) != null) {
	        	//System.out.println(str);
	        	String [] word = line.split("[\t]");
	        	//System.out.println(word[2]);
	        	if ( prevWord.equals(word[2])){
	        		System.out.println(prevLine);
	        		System.out.println(line);
	        	}
	        	prevWord = word[2];
	        	prevLine = line;
	        }
	        in.close();
	    } catch (IOException e) {
	    	System.err.println(e);
	    }
	}
	
	public static void main(String [] args){
		GetLine getLine = new GetLine();
		getLine.parse(args[0]);
	}
	
}