How to replace multiple HTML titles in a directory using Java?

Question

I am creating a Java Application to replace or a title to an HTML file. I have a folder of HTML files that I want to change the titles for and I don't want to manually do every HTML file. I want to read the HTML, find the title tag (i.e. <title>Some Title Here</title>), and replace it with a new title (i.e <title>Some New Title Here</title>) in each HTML file in the folder.

Can this be done using java? And how?

Keep getting IO Exceptions

for (int i = 0; i < listOfFiles.length; i++) {
    if (listOfFiles[i].isFile()) {
        File file = new File(listOfFiles[i].getName());
        BufferedReader in = new BufferedReader(new FileReader(file));
        String line = in.readLine();
        while (line != null) {
            if (line.contains(type)) {
                line = line.replaceAll(
                        "(<title>[A-Za-z0-9\\s]+</title>)",
                        "<title>New title</title>");
            }

            lines.add(line);
            line = in.readLine();
        }
        in.close();

        PrintWriter out = new PrintWriter(listOfFiles[i]);
        for (String l : lines)
            out.println(l);
        out.close();

        System.out.println("File " + listOfFiles[i].getName());
    } else if (listOfF`enter code here`iles[i].isDirectory()) {
        System.out.println("Directory " + listOfFiles[i].getName());
    }

Related: http://stackoverflow.com/q/1934248/1065197 – Luiggi Mendoza May 14 '14 at 21:48 — Luiggi Mendoza, May 14 '14 at 21:48

score 1 · Answer 1 · edited May 23 '17 at 12:25

1

You can read the content of each file and use a regular expression to replace the title like this:

package replacetitle;

import java.io.*;
import java.util.*;

public class ReplaceTitle {
    public static void main(String[] args) {
        try {
            File file = new File("c:\\demo.html");
            replaceSelected(file, "<title>");
        } catch(IOException ex) {
            System.out.println(ex.toString());
        }
    }

    public static void replaceSelected(File file, String type) throws IOException {
        // we need to store all the lines
        List<String> lines = new ArrayList<String>();

        // first, read the file and store the changes
        BufferedReader in = new BufferedReader(new FileReader(file));
        String line = in.readLine();
        while (line != null) {
            if(line.contains(type)) {
                line = line.replaceAll("(<title>[A-Za-z0-9\\s]+</title>)","<title>New title</title>");
            }

            lines.add(line);
            line = in.readLine();
        }
        in.close();

        // now, write the file again with the changes
        PrintWriter out = new PrintWriter(file);
        for (String l : lines)
            out.println(l);
        out.close();
    }
}

And then save the file.

Hope it help.

Based on this question.

edited May 23 '17 at 12:25

Community

1
1

answered May 14 '14 at 21:55

Sergio Flores

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Please read: [RegEx match open tags except XHTML self-contained tags](http://stackoverflow.com/q/1732348/1065197). – Luiggi Mendoza May 14 '14 at 22:01
Yeah, isn't going to parse an entire [X]HTML, but helps to replace just the "Anything" that is what he needs. – Sergio Flores May 14 '14 at 22:17
What would happen if the `` is written in 2 or more lines? How this RegEx will handle it? – Luiggi Mendoza May 14 '14 at 22:20
I know, but generally a title tag appears just once in an HTML file, but that's not the real problem. – Sergio Flores May 14 '14 at 22:41
The real problem is to even advice to use regex for HTML parsing. It is plain wrong. It is not the right solution, and it won't be **ever**. – Luiggi Mendoza May 14 '14 at 22:43
@LuiggiMendoza: I don't think byoigres is at all suggesting that OP parse HTML using regular expressions. They are suggesting that replacing a string in a well-defined position is a valid use case for RegExp, which it is. – Whymarrh May 14 '14 at 23:26
@byoigres how could I modify that code to make the application read from a folder of HTML files and do the same thing for each HTML file? – WillieS1212 May 14 '14 at 23:42
@user3638544 you can use [this code](http://stackoverflow.com/a/5694398/1301872) and mix it up with the code above. – Sergio Flores May 14 '14 at 23:49
@byoigres one questionif you dont mind. what is type? Where is that variable at in the code? – WillieS1212 May 15 '14 at 00:36
@user3638544 type is the second string parameter which contains the value `` – Sergio Flores May 15 '14 at 01:30
@byoigres Im getting an File not found exceptions. can you take a look? – WillieS1212 May 15 '14 at 14:25

How to replace multiple HTML titles in a directory using Java?

1 Answers1