Can you please tell me how to make substring replacement in strings using regular expressions? In the text ( html ) there are so-called variables for which you need to make a replacement - %str% . I search with Matcher all the matches, I find. but here's how to do that to replace this value with the one I need.

Code:

 Pattern pattern = Pattern.compile("%(\\w.*)%"); Matcher matcher = pattern.matcher(html); StringBuffer buffer = new StringBuffer(); while (matcher.find()) { }
  • Something like this , huh? - Wiktor Stribiżew
  • @ WiktorStribiżew yes. problem solved. - Tsyklop
  • I added the answer. - Wiktor Stribiżew

1 answer 1

You can use the Matcher#appendReplacement , with which you can perform a replacement dynamically, based on the resulting match.

Here is an example code :

 import java.util.*; import java.util.regex.*; import java.lang.*; import java.io.*; class Ideone { public static void main (String[] args) throws java.lang.Exception { String s = "Код %здесь%, кот %там%"; HashMap<String, String> h = new HashMap<String, String>(); h.put("здесь" , "на земле"); h.put("там" , "в раю"); System.out.println(convertTree(s, h)); } private static String convertTree(String s, HashMap<String, String> conv) { Pattern pattern = Pattern.compile("%(\\p{L}+)%"); // Задаем шаблон Matcher m = pattern.matcher(s); // Инициализация Matcher StringBuffer result = new StringBuffer(); // Буфер для конечного значения while (m.find()) { // Проверка на совпадение if (conv.containsKey(m.group(1))) { // Проверка на наличие ключа m.appendReplacement(result, conv.get(m.group(1))); // Подставляем значение из HashMap } else { m.appendReplacement(result, m.group(0)); // Или найденное совпадение, если ключ не найден } } m.appendTail(result); // Добавить остаток строки return result.toString(); } }