Replace words in parenthesis

Question

I have a question about replacing words. I have some strings, each of which looks like this:

String string = "today is a (happy) day, I would like to (explore) more about Java."

I need to replace the words that have parentheses. I want to replace "(happy)" with "good", and "(explore)" with "learn".

I have some ideas, but I don't know how.

for (int i = 0; i <= string.length(), i++) {
  for (int j = 0; j <= string.length(), j++
    if ((string.charAt(i)== '(') && (string.charAt(j) == ')')) {
      String w1 = line.substring(i+1,j);
      string.replace(w1, w2)
    }
  }
}

My problem is that I can only replace one word with one new word...

I am thinking of using a scanner to prompt me to give a new word and then replace it, how can I do this?

Answer 1

The appendReplacement and appendTail methods of Matcher are designed for this purpose. You can use a regex to scan for your pattern--a pair of parentheses with a word in the middle--then do whatever you need to do to determine the string to replace it with. See the javadoc.

An example, based on the example in the javadoc. I'm assuming you have two methods, replacement(word) that tells what you want to replace the word with (so that replacement("happy") will equal "good" in your example), and hasReplacement(word) that tells whether the word has a replacement or not.

Pattern p = Pattern.compile("\\((.*?)\\)");
Matcher m = p.matcher(source);
StringBuffer sb = new StringBuffer();
while (m.find()) {
    String word = m.group(1);
    String newWord = hasReplacement(word) ? replacement(word) : m.group(0);
    m.appendReplacement(sb, newWord); // appends the replacement, plus any not-yet-used text that comes before the match
}
m.appendTail(sb); // appends any text left over after the last match
String result = sb.toString();

Answer 2

Use below code for replacing the string.

String string = "today is a (happy) day, I would like to (explore) more about Java.";
string = string.replaceAll("\\(happy\\)", "good");
string = string.replaceAll("\\(explore\\)", "learn");
System.out.println(string);`

Answer 3

What you can do is run a loop from 0 to length-1 and if loop encounters a ( then assign its index to a temp1 variable. Now go on further as long as you encounter ).Assign its index to temp2 .Now you can replace that substring using string.replace(string.substring(temp1+1,temp2),"Your desired string")).

Answer 4

No need to use the nested loops. Better use one loop and store the index when you find opening parenthesis and also for close parenthesis and replace it with the word. Continue the same loop and store next index. As you are replacing the words in same string it changes the length of string you need to maintain copy of string and perform loop and replace on different,

Answer 5

Do not use nested for loop. Search for occurrences of ( and ). Get the substring between these two characters and then replace it with the user entered value. Do it till there are not more ( and ) combinations left.

import java.util.Scanner;

public class ReplaceWords {

    public static String replaceWords(String s){
        while(s.contains(""+"(") && s.contains(""+")")){
            Scanner keyboard = new Scanner(System.in);
            String toBeReplaced = s.substring(s.indexOf("("), s.indexOf(")")+1);
            System.out.println("Enter the word with which you want to replace "+toBeReplaced+" : ");
            String replaceWith = keyboard.nextLine();
            s = s.replace(toBeReplaced, replaceWith);
        }
        return s;
    }

    public static void main(String[] args) {
        String myString ="today is a (happy) day, I would like to (explore) more about Java.";
        myString = replaceWords(myString);
        System.out.println(myString);
    }
}

Answer 6

This snippet works for me, just load the HashMap up with replacements and iterate through:

import java.util.*;

public class Test
{
    public static void main(String[] args) {
        String string = "today is a (happy) day, I would like to (explore) more about Java.";
        HashMap<String, String> hm = new HashMap<String, String>();
        hm.put("\\(happy\\)", "good");
        hm.put("\\(explore\\)", "learn");

        for (Map.Entry<String, String> entry : hm.entrySet()) {
            String key = entry.getKey();
            String value = entry.getValue();
            string = string.replaceAll(key, value);
        }
        System.out.println(string);
    }
}

Remember, replaceAll takes a regex, so you want it to display "\(word\)", which means the slashes themselves must be escaped.