/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String str = "{\n  \"xxx\" : \"1234\",\n  \"yyy\" : \"1234\",\n  \"zzz\" : \"8888\"\n}"; 
 
		Matcher m = Pattern.compile(".*zzz\".*?\"(.*?)\"").matcher(str);
 
		while (m.find()){
			System.out.println("Captured content: " + m.group(1));
 
		}
 
 
	}
}

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