extract multiple instances of a pattern occuring in string?

Question

I have a String like following:

String text = "This is awesome
               Wait what?
               [[Foo:f1 ]]
               [[Foo:f2]]
               [[Foo:f3]]
               Some texty text
               [[Foo:f4]]

Now, I am trying to write a function:

public String[] getFields(String text, String field){
// do somethng
 }

enter code here should return [f1,f2,f3,f4] if i pass this text with field = "Foo"

How do i do this cleanly?

Answer 1

Use the pattern:

Pattern.compile("\\[\\[" + field + ":\\s*([\\w\\s]+?)\\s*\\]\\]");

and get the values of the first capturing group.

---

String text = "This is awesome Wait what? [[Foo:f1]] [[Foo:f2]]"
        + " [[Foo:f3]] Some texty text [[Foo:f4]]";

String field = "Foo";

Matcher m = Pattern.compile(
        "\\[\\[" + field + ":\\s*([\\w\\s]+?)\\s*\\]\\]").matcher(text);

while (m.find())
    System.out.println(m.group(1));

f1
f2
f3
f4

You can put all the matches in a List<String> and convert that to an array.