Important topics for interviews(only written):

COREJAVA:

1.Inheritance(Single, Multilevel):

Single Inheritance:


public class A {
  public void test1() {
    System.out.println("test1");

  }
}

public class B extends A {
  public void test2() {
    System.out.println("test2");
  }

  public static void main(String[] args) {
    B b1 = new B();
    b1.test1();
    b1.test2();
  }

}

Multilevel Inheritance:

public class C {
  public void test3() {
    System.out.println("test3");
  }

}

public class A extends C {
  public void test1() {
    System.out.println("test1");

  }}
public class B extends A {
  public void test2() {
    System.out.println("test2");
  }

  public static void main(String[] args) {
    B b1 = new B();
    b1.test1();
    b1.test2();
    b1.test3();
  }

}

2.Polymorphism(Method overloading,Method overriding):

Method overloading:

public class Employee {
  public void findEmpId(int age) {
    System.out.println("123");
  }

  public void findEmpId() {
    System.out.println("123");
  }

  public static void main(String[] args) {
    Employee e = new Employee();
    e.findEmpId();
    e.findEmpId(765);
  }

}

Method overriding:

public class AxisBank {
  public void fixedDeposite() {
    System.out.println("5%");

  }
}
public class HDFCBank extends AxisBank {
  public void fixedDeposite() {
    System.out.println("10%");

  }

  public static void main(String[] args) {
    AxisBank bank = new HDFCBank();
    bank.fixedDeposite();

  }

}

3.Abstarctions(interface,abstarct class,multiple inheritance through interface):
Abstract class:

public abstract class Bank {
  public abstract void savingAcct();

  public abstract void currentAcct();

  public void branchDetails() {
    System.out.println("Chennai");
  }

}


public class HDFCBank extends Bank {

  public void savingAcct() {
    System.out.println("6%");

  }

  public void currentAcct() {
    System.out.println("8%");
  }

  public static void main(String[] args) {
    Bank b = new HDFCBank();
    b.savingAcct();
    b.currentAcct();
    b.branchDetails();
  }

}



public class AxisBank extends Bank {

  public void savingAcct() {
    System.out.println("5%");

  }

  public void currentAcct() {
    System.out.println("10%");
  }

  public static void main(String[] args) {
    Bank b = new AxisBank();
    b.savingAcct();
    b.currentAcct();
    b.branchDetails();
  }

}

Interface:

public interface Bank {
  public abstract void savingAcct();

  public void currentAcct();

}


public class HDFCBank implements Bank {

  public void savingAcct() {
    System.out.println("6%");

  }

  public void currentAcct() {
    System.out.println("8%");
  }

  public static void main(String[] args) {
    Bank b = new HDFCBank();
    b.savingAcct();
    b.currentAcct();
  }

}



public class AxisBank implements Bank {

  public void savingAcct() {
    System.out.println("5%");

  }

  public void currentAcct() {
    System.out.println("10%");
  }

  public static void main(String[] args) {
    Bank b = new AxisBank();
    b.savingAcct();
    b.currentAcct();
  }

}


Multiple Inheritance through Interface:

public interface I1 {
  void test1();
}


public interface I2 {
  void test2();
}


public class C implements I1, I2 {

  public void test2() {
    System.out.println("test2");
  }

  public void test1() {
    System.out.println("test1");
  }

  public static void main(String[] args) {
    C c1 = new C();
    c1.test1();
    c1.test2();
  }

}



4.Insert values in list/userdefine and iterate values using foreach/for:

Insert values in List:

import java.util.ArrayList;
import java.util.List;

public class Employee {
  public static void main(String[] args) {
    List<Integer> emp = new ArrayList<>();
    emp.add(12);
    emp.add(122);
    emp.add(123);
    emp.add(124);
    emp.add(125);

    // for loop

    for (int i = 0; i < emp.size(); i++) {
      System.out.println(emp.get(i));
    }

    // Enhanced for loop
    for (Integer i : emp) {
      System.out.println(i);

    }
  }

}


Insert values in List with userdefine list:

public class Employee {
  private int id;
  private String name;

  public int getId() {
    return id;
  }

  public void setId(int id) {
    this.id = id;
  }

  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }

}



import java.util.ArrayList;
import java.util.List;

public class Details {
  public static void main(String[] args) {
    List<Employee> emp = new ArrayList<>();

    Employee e1 = new Employee();
    e1.setId(12);
    e1.setName("Vel");

    Employee e2 = new Employee();
    e2.setId(13);
    e2.setName("Bala");

    emp.add(e1);
    emp.add(e2);

    for (Employee x : emp) {
      System.out.println(x.getId());
      System.out.println(x.getName());
    }

  }

}

5.Insert values in Map/userdefine Map and iterate values:
Insert the values in Map:
package org.cts.toyota.login;

import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

public class Details {
  public static void main(String[] args) {

    Map<Integer, String> emp = new HashMap<>();
    emp.put(10, "Selenium");
    emp.put(20, "Webdriver");
    emp.put(30, "Junit");
    emp.put(40, "TestNG");
    emp.put(50, "SQL");
    Set<Entry<Integer, String>> e = emp.entrySet();
    for (Entry<Integer, String> x : e) {
      System.out.println(x.getKey());
      System.out.println(x.getValue());

    }

  }

}

Insert the values in userdefine Map:

public class Employee {
  private int id;
  private String name;

  public int getId() {
    return id;
  }

  public void setId(int id) {
    this.id = id;
  }

  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }

}



import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

public class Details {
  public static void main(String[] args) {

    Map<Integer, Employee> emp = new HashMap<>();

    Employee e1 = new Employee();
    e1.setId(12);
    e1.setName("bala");

    Employee e2 = new Employee();
    e2.setId(312);
    e2.setName("Guna");

    emp.put(10, e1);
    emp.put(20, e2);

    Set<Entry<Integer, Employee>> e = emp.entrySet();
    for (Entry<Integer, Employee> x : e) {
      System.out.println(x.getKey());
      System.out.println(x.getValue().getId());
      System.out.println(x.getValue().getName());
    }

  }

}



6.JDBC connection steps code:

JDBC connection steps:

package org.cts.toyota.login;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class Details {
  public static void main(String[] args) {
    Connection con = null;
    try {
      // load the driver
      Class.forName("com.mysql.jdbc.Driver");
      // connec to db
      con = DriverManager.getConnection("jdbc:mysql://127.0.0.1localhost:portnum/schemaName", "username",
          "password");
      // write a sql query
      String sql = "Select * from employees";
      PreparedStatement ps = con.prepareStatement(sql);
      // execute query
      ResultSet rs = ps.executeQuery();
      // iterate
      while (rs.next()) {
        int empId = rs.getInt("id");
        String empName = rs.getString("name");
      }

    } catch (Throwable e) {
      e.printStackTrace();
    } finally {
      try {
        // close db connection
        con.close();
      } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
      }
    }

  }

}

7.Code for singleton class:
public class Employee {
  private static Employee emp = null;

  private Employee() {
  }

  public static Employee getObject() {
    if (emp == null) {
      emp = new Employee();
    }
    return emp;

  }

  public void getId() {
    System.out.println("12");
  }

  public void getName() {
    System.out.println("Vel");
  }
}



public class Details {
  public static void main(String[] args) {
    Employee e = Employee.getObject();
    e.getId();
    e.getName();

  }

}


8.userdefine exception:

public class MyException extends Exception {
  @Override
  public String getMessage() {
    return "Not Found";
  }

}



public class Details {
  public static void main(String[] args) {
    String env = "down";
    if (env.equals("down")) {
      try {
        throw new MyException();
      } catch (MyException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
      }
    }
  }

}

Windows Handling
Syntax:
driver.switchTo().window(String Url) 
driver.switchTo().window(String title) 
driver.switchTo().window(String windows)

driver.getwindowHandle()-parent 
driver.getwindowHandles()--child

Set<String> all=driver.getwindowsHandles();
List<String> emp=new ArrayList<String>();
emp.addAll(all);
driver.switchTo().window(emp.get(index));
Program:
import java.util.Set;

import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;

public class Employee {
  public static void main(String[] args) {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");
    // parent window id
    String pWid = driver.getWindowHandle();
    // all windows
    Set<String> allWindows = driver.getWindowHandles();
    for (String x : allWindows) {
      if (!pWid.equals(x)) {
        driver.switchTo().window(x);
      }

    }

  }
}

webtable
Syntax:
List<WebElement> tRows=driver.findElements(By.tagName("tr"));
for(WebElement x:tRows){
List<WebElement> tData=driver.findElements(By.tagName("td"));
for(WebElement y:tData){
String name=y.getText();
sysout(name);
}
}
Program:
package org.cts.toyota.login;

import java.util.List;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;

public class Employee {
  public static void main(String[] args) {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");
    // Enhnaced for loop
    List<WebElement> tRows = driver.findElements(By.tagName("tr"));
    for (WebElement rows : tRows) {
      List<WebElement> tData = rows.findElements(By.tagName("td"));
      for (WebElement data : tData) {
        System.out.println(data.getText());

      }
    }

    // for loop
    for (int i = 0; i < tRows.size(); i++) {
      List<WebElement> tData = tRows.get(i).findElements(By.tagName("td"));
      for (int j = 0; j < tData.size(); j++) {
        System.out.println(tData.get(j).getText());
      }
    }
  }
}

ScreenShot
Syntax:
TakeScreenShot tk=(TakeScreenShot)driver;
File src=tk.getScreenShotAs(OutPut type.FILE);
File desc=new File("path");
FileUtiles.copyFile(Src,desc);
Program:
import java.io.File;
import java.io.IOException;

import org.apache.commons.io.FileUtils;
import org.openqa.selenium.OutputType;
import org.openqa.selenium.TakesScreenshot;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;

public class Employee {
  public static void main(String[] args) throws IOException {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");

    TakesScreenshot tk = (TakesScreenshot) driver;
    File f = tk.getScreenshotAs(OutputType.FILE);
    FileUtils.copyFile(f, new File("dest location"));

  }
}

ScroolDown
Syntax:
JavaScriptExecutor jk=(JavaScriptExecutor)driver;
jk.executeScript("arguments[0].ScrollIntoview(true)",WebElement)
ScroolUp
JavaScriptExecutor jk=(JavaScriptExecutor)driver;
jk.executeScript("arguments[0].ScrollIntoview(false)",WebElement)
Program:
package org.cts.toyota.login;

import java.io.IOException;

import org.openqa.selenium.By;
import org.openqa.selenium.JavascriptExecutor;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;

public class Employee {
  public static void main(String[] args) throws IOException {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");

    WebElement down = driver.findElement(By.id("email"));
    JavascriptExecutor js = (JavascriptExecutor) driver;
    // down
    js.executeScript("arguments[0].scrollIntoView(true)", down);
    // up
    js.executeScript("arguments[0].scrollIntoView(false)", down);

  }
}

link count
Program:
import java.io.IOException;
import java.util.List;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;

public class Employee {
  public static void main(String[] args) throws IOException {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");
    List<WebElement> allLinks = driver.findElements(By.tagName("a"));
    int linksCount = allLinks.size();
    System.out.println(linksCount);
  }
}

Broken link count
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
Try
{
connection.connect();
 String response = connection.getResponseMessage();         
 connection.disconnect();
  return response;
 }
 catch(Exception exp)
 {
 return exp.getMessage();
 }        
 }

Select
Syntax:
Select refName=new Select(webElement);
refName.selectByIndex();
refName.selectByVisibleText();
refName.selectByValue();
Methods in Select:
selectByIndex();
selectByVisibleText();
selectByValue();
getOptions();
getAllSelectedOptions();
getFirstSelectedOptions();
isMultiple();
deSelectByIndex();
deSelectByVisibleText();
deSelectByValue();
deSelectAll();
For print the selected value:
import java.io.IOException;
import java.util.List;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.support.ui.Select;

public class Employee {
  public static void main(String[] args) throws IOException {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");
    WebElement w = driver.findElement(By.id("country"));
    Select s = new Select(w);
    // foreach
    List<WebElement> emp = s.getAllSelectedOptions();
    for (WebElement x : emp) {
      System.out.println(x.getText());

    }
    // for loop
    for (int i = 0; i < emp.size(); i++) {
      System.out.println(emp.get(i).getAttribute("value"));

    }

  }
}

For print all the options:
package org.cts.toyota.login;

import java.io.IOException;
import java.util.List;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.support.ui.Select;

public class Employee {
  public static void main(String[] args) throws IOException {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");
    WebElement w = driver.findElement(By.id("country"));
    Select s = new Select(w);
    // select all values by index
    List<WebElement> optionsAll = s.getOptions();
    for (int i = 0; i < optionsAll.size(); i++) {
      s.selectByIndex(i);

    }
    // select all values by value with for loop
    for (int i = 0; i < optionsAll.size(); i++) {
      s.selectByValue(optionsAll.get(i).getAttribute("value"));

    }
    // select all values by value with foreach
    for (WebElement x : optionsAll) {
      s.selectByValue(x.getAttribute("value"));

    }
    // select values by visibletext with for loop
    for (int i = 0; i < optionsAll.size(); i++) {
      s.selectByVisibleText(optionsAll.get(i).getText());

    }

    // select all values by visible text with foreach
    for (WebElement x : optionsAll) {
      s.selectByVisibleText(x.getText());
    }

  }
}


Action:
mouseOverAction:
Actions refName=new Actions(driver);
refName.moveToElement(webElement).perform();
Program:
package org.cts.toyota.login;

import java.io.IOException;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.interactions.Actions;

public class Employee {
  public static void main(String[] args) throws IOException {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");
    // drag and drop
    WebElement from = driver.findElement(By.id("from"));
    Actions acc = new Actions(driver);
    acc.moveToElement(from).perform();
  }
}

dropAndDrag:
Actions refName=new Actions(driver);
refName.dropAndDrag(webEle1,wenEle2).perform();
Program:
import java.io.IOException;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.interactions.Actions;

public class Employee {
  public static void main(String[] args) throws IOException {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");
    // drag and drop
    WebElement from = driver.findElement(By.id("from"));
    WebElement dest = driver.findElement(By.id("to"));
    Actions acc = new Actions(driver);
    acc.dragAndDrop(from, dest).perform();
  }
}

contextClick:
Actions refName=new Actions(driver);
refName.contectClick(webElement).perform();
Program:
import java.io.IOException;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.interactions.Actions;

public class Employee {
  public static void main(String[] args) throws IOException {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");
    // drag and drop
    WebElement from = driver.findElement(By.id("from"));
    Actions acc = new Actions(driver);
    acc.contextClick(from).perform();
  }
}

DoubleClick:
Actions refName=new Actions(driver);
refName.doubleClick(webElement).perform();
Program:
import java.io.IOException;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.interactions.Actions;

public class Employee {
  public static void main(String[] args) throws IOException {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");
    // drag and drop
    WebElement from = driver.findElement(By.id("from"));
    Actions acc = new Actions(driver);
    acc.doubleClick(from).perform();
  }
}

Implict wait:
*It make the whole webdriver wait for that particular time we mention.
*driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS)
Explict wait:
*It make the particular webelememt wait for that particular time we mention.
*We can also mention the condition for which the webelement will wait.
*WebDriverWait wait = new WebDriverWait(driver, 10);
 WebElement element = wait.until(ExpectedConditions.somecondition(By.id("someid")));
Fluent wait:
*Each FluentWait instance defines the maximum amount of time to wait for a condition, as well as the frequency with which to check the condition. 
*The user may configure the wait to ignore specific types of exceptions whilst waiting, such as NoSuchElementExceptions when searching for an element on the page.
Xpath functions
Following: 
*Selects all elements in the document of the current node.
sibling:
*Select the following siblings of the context node. Siblings are at the same level of the current node .
Parent:
*Selects the parent of the current node.
Child : 
*Selects all children elements of the current node.
Preceding: 

*Select all nodes that come before the current node.
Alert
Alert refName=driver.SwitchTo.alert();
Program:
import java.io.IOException;

import org.openqa.selenium.Alert;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;

public class Employee {
  public static void main(String[] args) throws IOException {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");
    // alert switch
    Alert al = driver.switchTo().alert();
    // ok
    al.accept();
    // cancell
    al.dismiss();
    // insert
    al.sendKeys("yes");

  }
}

Frames:
Syntax:
driver.switchTo().frame("name");
driver.switchTo().frame(index);
driver.switchTo().frame(WebElement);
Program:
import java.io.IOException;
import java.util.List;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;

public class Employee {
  public static void main(String[] args) throws IOException {
    System.setProperty("webdriver.chrome.driver", "path");
    WebDriver driver = new ChromeDriver();
    driver.get("url");
    List<WebElement> emp = driver.findElements(By.tagName("iframe"));
    int frameCount = emp.size();
    System.out.println(frameCount);
  }
}

Reusable code for sendkeys:
public static void type(WebElement element,String name)
{
element.sendkeys(name);
}
Reusable code for button:
public static void type(WebElement element)
{
element.click();
}
Reusable code for driver close:
public static void type(WebDriver driver)
{
driver.quit();
}

Reusable code for Driver lanuch:

public static webDriver getDriver(String url){
System setProperty("webdriver.chrome.driver","path");
WebDriver driver=new ChromeDriver();
driver.get(url);
return driver;
}