Open file, read line by line, do string manipulation

Strings example from a Well House Consultants training course
More on Strings [link]

This example is described in the following article(s):
• String handling - from first steps to practical examples - [link]

Source code: Vest.java Module: J707

import java.io.*;

/* Open file, read line by line, do string manipulation

Some basic string handling functions and also some file
stuff (which comes up in more detail later) so that you
can get a really practical feel for a real job that's
doing something quite straightforward to a heavy flow
of data */

public class Vest {
        public static void main (String [] args)
                                throws FileNotFoundException, IOException {

// String handling basics - run a method on a string

                String Copyright = "This is mine and you SHUNNAE touch";
                System.out.println(Copyright.toLowerCase());

// String handling basics - echo command line params

                for (int k=0; k<args.length; k++) {
                        System.out.println(args[k]);
                }

// String handling basics - read (and echo) whole file

                int countplace = 0, countlines = 0;
                int iptop; String RemoteIp;
                BufferedReader Suck = new BufferedReader(new FileReader(args[0]));
                String Stuff;
                while ((Stuff = Suck.readLine()) != null) {

// String handling basics - look for one string in another

                        countlines ++;
                        iptop = Stuff.indexOf(" ");
                        RemoteIp = Stuff.substring(0,iptop);
                        if (Stuff.indexOf("Swindon") >= 0) {
                                        System.out.println(RemoteIp);
                                        countplace++;

                        }
                }

// Print out summary report too

                System.out.println("Total " + countlines);
                System.out.println("Matched " + countplace);
        }
}

/* Sample Output

wizard:jn10 graham$ java Vest ac_20101103
this is mine and you shunnae touch
ac_20101103
66.249.66.174
66.249.66.174
67.195.112.232
66.249.66.174
66.249.66.174
66.249.66.174
66.249.66.174
66.249.66.174
66.249.66.174
66.249.66.174
193.47.80.37
217.160.182.81
62.189.77.47
62.189.77.47
62.189.77.47
62.189.77.47
67.195.112.232
66.249.65.99
67.195.112.232
189.32.14.180
67.195.112.232
67.195.112.232
67.195.115.231
220.181.94.224
67.195.112.232
66.249.65.99
81.52.143.36
86.45.252.202
86.45.252.202
86.45.252.202
195.42.102.21
66.249.65.118
208.115.111.250
66.249.65.65
207.46.13.42
24.226.108.128
24.226.108.128
24.226.108.128
24.226.108.128
24.226.108.128
207.46.13.136
217.160.182.81
66.249.65.65
Total 159715
Matched 43
wizard:jn10 graham$

*/

Learn about this subject

This module and example are covered on the following public courses:
* Learning to Program in Java
* Java Bootcamp
* Java Programming for the Web
Also available on on site courses for larger groups

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Other Examples

This example comes from our "Strings" training module. You'll find a description of the topic and some other closely related examples on the "Strings" module index page.

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