Remove HTML tags from a String

Use a HTML parser instead of regex. This is dead simple with Jsoup.

public static String html2text(String html) {    return Jsoup.parse(html).text();}

Jsoup also supports removing HTML tags against a customizable whitelist, which is very useful if you want to allow only e.g. <b>, <i> and <u>.

See also:

• RegEx match open tags except XHTML self-contained tags
• What are the pros and cons of the leading Java HTML parsers?
• XSS prevention in JSP/Servlet web application

If you're writing for Android you can do this...

android.text.HtmlCompat.fromHtml(instruction, HtmlCompat.FROM_HTML_MODE_LEGACY).toString()

If the user enters <b>hey!</b>, do you want to display <b>hey!</b> or hey!? If the first, escape less-thans, and html-encode ampersands (and optionally quotes) and you're fine. A modification to your code to implement the second option would be:

replaceAll("\\<[^>]*>","")

but you will run into issues if the user enters something malformed, like <bhey!</b>.

You can also check out JTidy which will parse "dirty" html input, and should give you a way to remove the tags, keeping the text.

The problem with trying to strip html is that browsers have very lenient parsers, more lenient than any library you can find will, so even if you do your best to strip all tags (using the replace method above, a DOM library, or JTidy), you will still need to make sure to encode any remaining HTML special characters to keep your output safe.