Java RegEx problem, need help

[shin_orochi]

Hi all,

i am trying to learning about regular expression in java. i have some problem, here my code :

import java.io.*;
import java.util.regex.Pattern;
import java.util.regex.Matcher;
import java.io.Console;

class RegularExpression {
  public static void main(String args[]) {
    try {
		Console console = System.console();


         Pattern pattern = Pattern.compile("ing|les");
         Matcher matcher = pattern.matcher("About 2 months after being laid, the turtles hatchlings emerge from the sand and are put into sea water tanks");


		 boolean found = false;
		 while (matcher.find()) {
			 console.format("I found the text" +
				 " \"%s\" starting at " +
				 "index %d and ending at index %d.%n",
				 matcher.group(),
				 matcher.start(),
				 matcher.end());

			 found = true;
		 }
		 if(!found){
			 console.format("No match found.%n");
		}
     } catch (Exception e) {
      System.err.println(e);
    }
  }
}

and the result are :

I found the text "ing" starting at index 23 and ending at index 26.
I found the text "les" starting at index 41 and ending at index 44.
I found the text "ing" starting at index 51 and ending at index 54.

my problem is, how to display the word "being" instead "I found the text "ing" starting at index 23 and ending at index 26." or "turtles" instead of "I found the text "les" starting at index 41 and ending at index 44.".


Excuse for my English.

[DarrylBurke]

Look around the FAQs section of this site and discover how to use code tags. I've added them for you this time.

So, you want to capture all non-whitespace characters preceding "ing|or"? Or is it all non-punctuation|whitespace characters? or non-numeric characters?

First formulate your requirements. Then try to illustrate them with examples. Examples without specs are meaningless.

A couple of learning resources: Regular-Expressions.info - Regex Tutorial, Examples and Reference - Regexp Patterns and Lesson: Regular Expressions (The Java™ Tutorials > Essential Classes)

db

[shin_orochi]

hi db,

sorry for the mistake.

yes, i want to capture the characters preceding "ing|or"

[Fubarable]

Have a look at this Regular Expressions Tutorial. I think that the shorthand character classes, word boundaries and the lookahead sections are likely most appropriate for your problem.

[shin_orochi]

why when i try to put "ing$" as the regex, it returns "No math found"

[DarrylBurke]

What did you think the regex "ing$" signifies?

db

[DarrylBurke]

hi db,

sorry for the mistake.

yes, i want to capture the characters preceding "ing|or"

You call that a specification? Whitespace characters are characters. Alpha characters are characters. Digit/numeric characters are characters. Punctuation characters are characters.

So

the characters preceding "ing|or"

would mean from the beginning of input up to each "ing|or"

db

[shin_orochi]

regex "ing$" will return any words ended with "ing", am i right?

[JosAH]

regex "ing$" will return any words ended with "ing", am i right?

Nope, the '$' indicates the end of the string. <-- this would match if there wasn't a period ;-)

kind regards,

Jos

[shin_orochi]

ooo i see,

then how to capture only the words ended with 'ing' ?

[DarrylBurke]

You've been given the links to two learning resources. One of the links has already been posted twoc.e

Are we to believe that you went through the material and are still unable to come up with an approximation of what might go into the regex? I'd sooner believe that you glanced at the pages and decided it might be easier to hang around here till someone spoonfeeds you the answer.

That's not going to happen. Not likely anyways.

And your specs are still vague and incomplete.

db

[shin_orochi]

yaay!! finally i solve it.

Thank you DB and JosAH.

it's not like i'm not read all those articles, i need sometime to understand it.

here is my code

import java.io.*;
import java.util.regex.Pattern;
import java.util.regex.Matcher;
import java.util.*;

class FileRead {
  public static void main(String args[]) {
    try {
		int count = 0;
		String txtFile;
		String str;
		Console console = System.console();
		boolean found = false;

		while (true) {
			Pattern pattern = Pattern.compile(console.readLine("%nEnter your regex: "));
			BufferedReader fileName = new BufferedReader(new InputStreamReader(System.in));
		 	System.out.print("Please enter directory of the file: ");
		 	System.out.flush();
		 	txtFile = fileName.readLine();
		 	FileInputStream fstream = new FileInputStream(txtFile);
		 	DataInputStream in = new DataInputStream(fstream);
			BufferedReader br = new BufferedReader(new InputStreamReader(in));

			while((str = br.readLine()) !=null){
				StringTokenizer token = new StringTokenizer(str);

				while(token.hasMoreTokens()) {
					str = token.nextToken();
					Matcher matcher = pattern.matcher(str);

					while (matcher.find()) {
						count++;
						System.out.println("i've found "+str);
						found = true;
					}
				}
			}

			System.out.println("Total word/s found= "+count);
			count = 0;
			if(!found) {
				System.out.println("No match found");
			}
		}
	}
	catch (Exception e) {
		System.err.println(e);
    }
  }
}

Thanks for the help, i really appreciate it.

[DarrylBurke]

i need sometime to understand it.

Very true.

here is my code

I don't see any regex in that code.

db

[JosAH]

I don't see any regex in that code.

The user has to enter one during runtime.

kind regards,

Jos

[DarrylBurke]

The user has to enter one during runtime.

I saw that, but how does it relate to the question asked in this thread?

db

[JosAH]

I saw that, but how does it relate to the question asked in this thread?

It was also about regular expressions?

kind regards,

Jos