Question

I need a Java code to take this text ” text1 [example1]http://example1.com [example2]http://example2.com text2 ….” and return it as the following:

text1 <a target='_blank' href='http://example1.com'>example1</a> <a target='_blank' href='http://example2.com'>example2</a> text2

i mean whenever it finds this pattern [example2]http://example2.com in a text to take and put it in html hyperlink. Please help.. that what i have done till now but its not working

    ViolationTableItem item = new ViolationTableItem(m_violation);
    String dataSource = "";
     String copyDataSource="";
    try {
        dataSource = item.getUi().getViolation().getBlackListEntries()
                .getDataSources();

        Matcher matcher = Pattern.compile(
                "(\\[.*?\\])(.*://[^<>[:space:]]+[[:alnum:]/])").matcher(
                dataSource);

        while (matcher.find()) {

            String matchedLink = matcher.group();

            Matcher nameMatcher = Pattern.compile("\\[.*?\\]").matcher(
                    matchedLink);
            String nameMatched = "";
            String nameMatched2 = "";
            String linkableText = "";
            String[] tst = matchedLink.split("\\[.*?\\]");
            for (int i = 1; i < tst.length; i++) {
                if (nameMatcher.find()) {
                    nameMatched = nameMatcher.group();
                    // System.out.println(nameMatched);
                    nameMatched2 = matchedLink.replace(nameMatched, "");
                    // System.out.println(nameMatched2);

                }
                if (tst[i] != null && !tst[i].equals("")) {
                    linkableText = "<a target='_blank' href='"
                            + tst[i]
                            + "'>"
                            + nameMatched.replaceAll("\\[", "").replaceAll(
                                    "\\]", "") + "</a>";
                    copyDataSource += dataSource.replace(matchedLink,
                            linkableText) + " ";
                }
            }

        }
    } catch (Exception ne){
        return copyDataSource;
    }
    return copyDataSource;

Thanks in advance!

Answer 1

You can do this easily with String.replaceAll():

String text = " text1 [example1]http://example1.com [example2]http://example2.com text2 ....";
String link = "<a target='_blank' href='$2'>$1</a>";
String newText = text.replaceAll("\\[(.*?)\\](.*?)(?=\\s)", link);
System.out.println(newText);

prints

text1 <a target='_blank' href='http://example1.com'>example1</a> <a target='_blank' href='http://example2.com'>example2</a> text2 ....

The regex looks for a pair of brackets, captures everything inside and after up until the next space, and replaces it with the link string.
$1 and $2 are used to find what was captured in the first and second parantheses.

If you dont want it to match any brackets, but for example just those followed by http://, just change the second (.*?) to (http://.*?).