java - regex replace all ignore case

Question

How do I ignore case in the below example?

outText = inText.replaceAll(word, word.replaceAll(" ", "~"));

Example:

Input:

inText = "Retail banking Wikipedia, the free encyclopedia Retail banking "
       + "From Wikipedia. retail banking industry."

word   = "retail banking"

Output

outText = "Retail~banking Wikipedia, the free encyclopedia Retail~banking " +
          "From Wikipedia. retail~banking industry."

Answer 1

To do case-insensitive search and replace, you can change

outText = inText.replaceAll(word, word.replaceAll(" ", "~"));

into

outText = inText.replaceAll("(?i)" + word, word.replaceAll(" ", "~"));

---

Avoid ruining the original capitalization:

In the above approach however, you're ruining the capitalization of the replaced word. Here is a better suggestion:

String inText="Sony Ericsson is a leading company in mobile. " +
              "The company sony ericsson was found in oct 2001";
String word = "sony ericsson";

Pattern p = Pattern.compile(word, Pattern.CASE_INSENSITIVE);
Matcher m = p.matcher(inText);

StringBuffer sb = new StringBuffer();

while (m.find()) {
  String replacement = m.group().replace(' ', '~');
  m.appendReplacement(sb, Matcher.quoteReplacement(replacement));
}
m.appendTail(sb);

String outText = sb.toString();

System.out.println(outText);

Output:

Sony~Ericsson is a leading company in mobile.
The company sony~ericsson was found in oct 2001