java regular expression find and replace

Question

I am trying to find environment variables in input and replace them with values.

The pattern of env variable is ${\\\\.}

Pattern myPatte         


        

Answer 1

Use groups once it is matched ${env1} will be your first group and then you use regex to replace what is in each group.

Pattern p = Pattern.compile("(${\\.})");
Matcher m = p.matcher(line);
while (m.find())
  for (int j = 0; j <= m.groupCount(); j++)
    //here you do replacement - check on the net how to do it;)