Example Checkbox in Dropdown Selenium WebDriver

package dayOne;

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

public class JobServe {


public static void main(String[] args) {

 WebDriver driver = new FirefoxDriver();

 driver.get("http://www.jobserve.com/in/en/Job-Search/");

 driver.findElement(By.xpath("/html/body/form/div[4]/div[1]/div[12]/div[1]/div/div[2]/div[2]/div/div[1]/div[2]/span/span")).click();

 driver.findElement(By.xpath("/html/body/form/div[4]/div[1]/div[12]/div[1]/div/div[2]/div[2]/div/div[1]/div[2]/div/div/div[1]/input")).click();

 int selection = 5;

String xpath_start = "/html/body/form/div[4]/div[1]/div[12]/div[1]/div/div[2]/div[2]/div/div[1]/div[2]/div/div/div[";
String xpath_end = "]/input";

driver.findElement(By.xpath(xpath_start + selection + xpath_end )).click(); 
}

}