How to pass two strings (Username and Password) one by one in the two different text fields (Username and Password) in webdriver (Java)

I am having two different Strings by name username and password. And i want to pass these string values one by one (ONLY one value from username and one value from password) into username and password text fields. I tried in two different ways but not sure where i am doing mistake. Below are my codes and O/P result. Expected: Two combinations (1st: @ and @, 2nd: test and test).

Expected O/P: username password username password

String[] username={"@", "test"};

String[] password= {"@", "test"};

1st method:

import java.util.concurrent.TimeUnit;

import org.openqa.selenium.By;

import org.openqa.selenium.WebDriver;

import org.openqa.selenium.firefox.FirefoxDriver;

public class TwoStrings {

public static void main(String[] args) {

String[] username={"@", "test"};

String[] password= {"@", "test"};

WebDriver d =new FirefoxDriver();

d.get("http://newtours.demoaut.com/mercurysignon.php");

d.manage().timeouts().implicitlyWait(30, TimeUnit.SECONDS);

for(String j:username){

d.findElement(By.name("userName")).clear();

d.findElement(By.name("userName")).sendKeys(j);

System.out.println("userName");

for(int i =0; i<password.length; i++){

d.findElement(By.name("password")).clear();

d.findElement(By.name("password")).sendKeys(password[i]);

System.out.println("password");

}

}

d.findElement(By.name("login")).click();

}

}

O/P: userName password password userName password password

2nd method which i tried:

import java.util.concurrent.TimeUnit;

import org.openqa.selenium.By;

import org.openqa.selenium.WebDriver;

import org.openqa.selenium.firefox.FirefoxDriver;

public class TwoStrings {

public static void main(String[] args) {

String[] username={"@", "test"};

String[] password= {"@", "test"};

WebDriver d =new FirefoxDriver();

d.get("http://newtours.demoaut.com/mercurysignon.php");

d.manage().timeouts().implicitlyWait(30, TimeUnit.SECONDS);

for(String j:username){

for(String k:password){

d.findElement(By.name("userName")).clear();

d.findElement(By.name("userName")).sendKeys(j);

System.out.println("userName");

d.findElement(By.name("password")).clear();

d.findElement(By.name("password")).sendKeys(k);

System.out.println("password");

}

}

d.findElement(By.name("login")).click();

}

}

O/P: userName password userName password userName password userName password