how call external class (contains selenium commands) in selenium test properly?
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I use Selenium Web Driver with JUnit in Eclipse. I want diminish my code by creating new classes for repitable steps. I want store this classes in separate files for convenience. For example this one of such classes:

    import org.openqa.selenium.ie.InternetExplorerDriver;

     //Login
    public class Login {
	private InternetExplorerDriver driver;

	String url;
	String name;
	String password;
	String language;
	public Login (String ur, String nam, String pass, String lang){
		url=ur;
		name=nam;
		password=pass;
		language=lang;
	}
     public void log_in (){
	 driver.get(url);
	 driver.findElement(By.name("username")).sendKeys(name);	
	 driver.findElement(By.name("password")).sendKeys(password);	
	 driver.findElement(By.name("language")).sendKeys(language);	
	 driver.findElement(By.name("logon_action")).click(); 
      }	 
      }

This is my main test:

    package bobsworld;

    import init.Login;

    import org.junit.Assert;
    import org.junit.Test;
    import org.openqa.selenium.Alert;
    import org.openqa.selenium.By;
    import org.openqa.selenium.WebDriver;
    import org.openqa.selenium.WebElement;
    import org.openqa.selenium.ie.InternetExplorerDriver;


    public class WebTest {
    private WebDriver driver;


    @Test
    public void testUnit() throws Exception {

    //Open new window
    System.setProperty("webdriver.ie.driver", "IEDriverServer.exe");
    driver = new InternetExplorerDriver();
		 
    //Login	
    init.Login login = new init.Login ("myurl", "log","pas","English");
	  login.log_in();
    }
The problem is with object driver. I get `java.lang.NullPointerException` and can't execute test. How should I organize call to Login and code to make my test work?
	

