/* 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) {
    String str = "email1@gmail.com , 'email2@gmail.com,email3@gmail.com, email4@gmail.com' "+
                ", 'email5@gmail.com ,email6@gmail.com';email7@gmail.com/email8@gmail.com";
 
    Matcher m = Pattern.compile("\\w+@\\w+.com").matcher(str);
    List<String> emailsList = new ArrayList<>();
 
    while (m.find()){
        emailsList.add(m.group());
    }
 
    String[]emailsArray = emailsList.toArray(new String[0]);  // if really need an array
    System.out.println(Arrays.toString(emailsArray));
}
}

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