What is the alternate way to send text in textbox of webpage with out using sendKeys() method ?

Note- Use Javascript to send text.
syntax-

((JavascriptExecutor)driver).executeScript("document.getElementById('attribute value of id').value='text which you want to pass'");

ex-
import java.util.concurrent.TimeUnit;
import org.openqa.selenium.JavascriptExecutor;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.firefox.FirefoxDriver;

public class WithoutSendKeys {
public static void main(String[] args) {
WebDriver driver = new FirefoxDriver();
driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
driver.get("https://accounts.google.com/ServiceLogin?sacu=1&scc=1...");
((JavascriptExecutor)driver).executeScript("document.getElementById('Email').value='sanjay'");
}
}

How to check whether the selectbox is singleListbox or multipleListBox.

Note- use the method getAttribute("multiple") , if it return 'true' then it is multipleListBox else if return null then it is singleListBox.

Sample html code- 

<select id="sdd">   //in this select box only one option can be selected

<option>idly</option>

<option>dosa</option>

<option>vada</option>

<option>tea</option>

</select>

<br>

Combo

<select id="mdd" multiple>  //in this select box only multiple option can be selected

<option>idly</option>

<option>dosa</option>

<option>vada</option>

<option>tea</option>

</select>

Script Code-

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.firefox.FirefoxDriver;

public class MultipleListBox {
    public static void main(String[] args) {
        WebDriver driver = new FirefoxDriver();
        driver.get("C:\\selenium\\Selenium_web.html"); 
/*here the url is my personal page, you can try for any url which has such scenario or you can develop your own html page having the above html code.*/
        System.out.println(driver.findElement(By.xpath("//select[@id='mdd']")).getAttribute("multiple")); // this will print true, which means it is multipleListBox
        System.out.println(driver.findElement(By.xpath("//select[@id='sdd']")).getAttribute("multiple"));//
// this will print null, which means it is singleListBox       
    }
}

How do I identify and click on hidden element present on web page?

 HTML :
------------------
 
<input id="reporting" class="main" type="checkbox" title="reporting" onclick="enableRadioButtons('reporting', 'reportingHidden', 'reportingCheck')"/>Reporting</td>


 SELENIUM CODE:
----------------------
JavaScriptExecutor js= javaScriptExecutor(driver);
js.executescript("onclick="enableRadioButtons('reporting', 'reportingHidden', 'reportingCheck')");

Print the name of friends with the status like one is online, busy, idle or offline in gmail chat.

Note- Please give the gmail id and password while runtime. (after pressing ctrl+f11).

import java.util.List;
import java.util.Scanner;
import java.util.concurrent.TimeUnit;
import org.openqa.selenium.By;
import org.openqa.selenium.NoSuchElementException;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.firefox.FirefoxDriver;

public class GmailOnlinePeople {

public static void main(String[] args) {
    WebDriver driver;
    Scanner in = new Scanner(System.in);
    System.out.println("Enter the gmail id: ");
    String emailId = in.next();
    System.out.println("Enter the pass: ");
    String pass = in.next();
 
    driver = new FirefoxDriver(); //open firefox browser
 
    //login to gmail
    driver.get("http://www.gmail.com");
    driver.manage().window().maximize();
    driver.manage().timeouts().implicitlyWait(40,TimeUnit.SECONDS);
    driver.findElement(By.name("Email")).sendKeys(emailId);
    driver.findElement(By.name("Passwd")).sendKeys(pass);
    driver.findElement(By.name("signIn")).click();
    String name="";
    //friends with available status
    try {
        List<WebElement> available = driver.findElements(By.xpath("//tr[td[img[contains(@alt,'Available')]]]//td[2]/span[1]"));
        System.out.println("number of friends with available status in the gmail chat: "+available.size());
        if(available.size()!=0){
            System.out.println("Name of the friends with Available status: ");
        }
        for (int i=0; i <available.size(); i++)
        {
            name = available.get(i).getAttribute("textContent");
            System.out.println((i+1)+") "+name);
        }
    } catch (NoSuchElementException e) {
        System.out.println("No one is there with available status.");
    }
   
  //friends with busy status in the gmail chat
    try {
        List<WebElement> busy = driver.findElements(By.xpath("//tr[td[img[@alt='Busy']]]//td[2]/span[1]"));
        System.out.println("number of friends with busy status in the gmail chat: "+busy.size());
        if(busy.size()!=0){
            System.out.println("Name of the friends with busy status: ");
        }
        for (int i=0; i <busy.size(); i++)
        {
            name = busy.get(i).getAttribute("textContent");
            System.out.println((i+1)+") "+name);
        }
    } catch (NoSuchElementException e) {
        System.out.println("No one is with busy status.");
    }
   
  //friends with idle status
    try {
        List<WebElement> idle = driver.findElements(By.xpath("//tr[td[img[@alt='Idle']]]//td[2]/span[1]"));
        System.out.println("number of friends with idle status in the gmail chat: "+idle.size());
        if(idle.size()!=0){
            System.out.println("Name of the friends with idle status: ");
        }
        for (int i=0; i <idle.size(); i++)
        {
            name = idle.get(i).getAttribute("textContent");
            System.out.println((i+1)+") "+name);
        }
    } catch (NoSuchElementException e) {
        System.out.println("No one is with idle status.");
    }
   
  //friends with offline status
    try {
        List<WebElement> offline = driver.findElements(By.xpath("//tr[td[img[@alt='Offline']]]//td[2]/span[1]"));
        System.out.println("number of friends offline in the gmail chat: "+offline.size());
        if(offline.size()!=0){
            System.out.println("Name of the friends offline: ");
        }
        for (int i=0; i <offline.size(); i++)
        {
            name = offline.get(i).getAttribute("textContent");
            System.out.println((i+1)+") "+name);
        }
    } catch (NoSuchElementException e) {
        System.out.println("No one is offline.");
    }
    driver.close();
}
}