Get values from json using multiregex

[theunreal]

Using Java Pattern, I used to have something like this:

public String getAttributeFromMessage(String receiveData, Pattern patternToSearch) {
		Matcher matcher = patternToSearch.matcher(receiveData);
		if (matcher.find()) {
			return  matcher.group(1);
		}
		return "";
	}

Using this library I did something like this:

String[] patterns = new String[]{
					"\"field1\":\\s*\"(.*?)\"",
					"\"field2\":\\s*(\\d+)(\\.\\d)?",
					"\"field3\":\\s*\"(.*?)\""
			};
			this.matcher = MultiPattern.of(patterns).matcher();
...
public String getAttributeFromMessage(String receiveData) {
		int[] match = this.matcher.match(receiveData);
                ??
	}

I'm not sure how I can extract the values that the matcher has found, using Java.pattern I could do matcher.group(1) to get the string.

Any idea?