Package org.openqa.selenium.support.decorators

Class WebDriverDecorator

java.lang.Object

org.openqa.selenium.support.decorators.WebDriverDecorator

Direct Known Subclasses:

EventFiringDecorator

@Beta
public class WebDriverDecorator
extends java.lang.Object

This class helps to create decorators for instances of WebDriver and derived objects, such as WebElements and Alert, that can extend or modify their "regular" behavior. It provides a flexible alternative to subclassing WebDriver.

Here is a general usage pattern:

1. implement a subclass of WebDriverDecorator that adds something to WebDriver behavior:
   public class MyWebDriverDecorator extends WebDriverDecorator { ... }
   (see below for details)
2. use a decorator instance to decorate a WebDriver object:
   WebDriver original = new FirefoxDriver(); WebDriver decorated = new MyWebDriverDecorator().decorate(original);
3. use the decorated WebDriver instead of the original one:
   decorated.get("http://example.com/"); ... decorated.quit();

By subclassing WebDriverDecorator you can define what code should be executed

• before executing a method of the underlying object,
• after executing a method of the underlying object,
• instead of executing a method of the underlying object,
• when an exception is thrown by a method of the underlying object.

The same decorator is used under the hood to decorate all the objects derived from the underlying WebDriver instance. For example, decorated.findElement(someLocator) automatically decorates the returned WebElement.

Instances created by the decorator implement all the same interfaces as the original objects.

When you implement a decorator there are two main options (that can be used both separately and together):

• if you want to apply the same behavior modification to all methods of a WebDriver instance and its derived objects you can subclass WebDriverDecorator and override some of the following methods: beforeCall(Decorated, Method, Object[]), afterCall(Decorated, Method, Object[], Object), call(Decorated, Method, Object[]) and onError(Decorated, Method, Object[], InvocationTargetException)
• if you want to modify behavior of a specific class instances only (e.g. behaviour of WebElement instances) you can override one of the overloaded createDecorated methods to create a non-trivial decorator for the specific class only.

Let's consider both approaches by examples.

One of the most widely used decorator examples is a logging decorator. In this case we want to add the same piece of logging code before and after each invoked method: public class LoggingDecorator extends WebDriverDecorator { final Logger logger = LoggerFactory.getLogger(Thread.currentThread().getName());

Constructor Summary

Constructors

Constructor	Description
WebDriverDecorator()

Method Summary

Modifier and Type	Method	Description
void	afterCall(Decorated<?> target, java.lang.reflect.Method method, java.lang.Object[] args, java.lang.Object res)
void	beforeCall(Decorated<?> target, java.lang.reflect.Method method, java.lang.Object[] args)
java.lang.Object	call(Decorated<?> target, java.lang.reflect.Method method, java.lang.Object[] args)
Decorated<org.openqa.selenium.Alert>	createDecorated(org.openqa.selenium.Alert original)
Decorated<org.openqa.selenium.virtualauthenticator.VirtualAuthenticator>	createDecorated(org.openqa.selenium.virtualauthenticator.VirtualAuthenticator original)
Decorated<org.openqa.selenium.WebDriver>	createDecorated(org.openqa.selenium.WebDriver driver)
Decorated<org.openqa.selenium.WebDriver.Navigation>	createDecorated(org.openqa.selenium.WebDriver.Navigation original)
Decorated<org.openqa.selenium.WebDriver.Options>	createDecorated(org.openqa.selenium.WebDriver.Options original)
Decorated<org.openqa.selenium.WebDriver.TargetLocator>	createDecorated(org.openqa.selenium.WebDriver.TargetLocator original)
Decorated<org.openqa.selenium.WebDriver.Timeouts>	createDecorated(org.openqa.selenium.WebDriver.Timeouts original)
Decorated<org.openqa.selenium.WebDriver.Window>	createDecorated(org.openqa.selenium.WebDriver.Window original)
Decorated<org.openqa.selenium.WebElement>	createDecorated(org.openqa.selenium.WebElement original)
protected <Z> Z	createProxy(Decorated<Z> decorated)
org.openqa.selenium.WebDriver	decorate(org.openqa.selenium.WebDriver original)
Decorated<org.openqa.selenium.WebDriver>	getDecoratedDriver()
java.lang.Object	onError(Decorated<?> target, java.lang.reflect.Method method, java.lang.Object[] args, java.lang.reflect.InvocationTargetException e)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

WebDriverDecorator

public WebDriverDecorator()

Method Detail

decorate

public final org.openqa.selenium.WebDriver decorate(org.openqa.selenium.WebDriver original)

getDecoratedDriver

public Decorated<org.openqa.selenium.WebDriver> getDecoratedDriver()

createDecorated

public Decorated<org.openqa.selenium.WebDriver> createDecorated(org.openqa.selenium.WebDriver driver)

createDecorated

public Decorated<org.openqa.selenium.WebElement> createDecorated(org.openqa.selenium.WebElement original)

createDecorated

public Decorated<org.openqa.selenium.WebDriver.TargetLocator> createDecorated(org.openqa.selenium.WebDriver.TargetLocator original)

createDecorated

public Decorated<org.openqa.selenium.WebDriver.Navigation> createDecorated(org.openqa.selenium.WebDriver.Navigation original)

createDecorated

public Decorated<org.openqa.selenium.WebDriver.Options> createDecorated(org.openqa.selenium.WebDriver.Options original)

createDecorated

public Decorated<org.openqa.selenium.WebDriver.Timeouts> createDecorated(org.openqa.selenium.WebDriver.Timeouts original)

createDecorated

public Decorated<org.openqa.selenium.WebDriver.Window> createDecorated(org.openqa.selenium.WebDriver.Window original)

createDecorated

public Decorated<org.openqa.selenium.Alert> createDecorated(org.openqa.selenium.Alert original)

createDecorated

public Decorated<org.openqa.selenium.virtualauthenticator.VirtualAuthenticator> createDecorated(org.openqa.selenium.virtualauthenticator.VirtualAuthenticator original)

beforeCall

public void beforeCall(Decorated<?> target,
                       java.lang.reflect.Method method,
                       java.lang.Object[] args)

call

public java.lang.Object call(Decorated<?> target,
                             java.lang.reflect.Method method,
                             java.lang.Object[] args)
                      throws java.lang.Throwable

Throws:

java.lang.Throwable

afterCall

public void afterCall(Decorated<?> target,
                      java.lang.reflect.Method method,
                      java.lang.Object[] args,
                      java.lang.Object res)

onError

public java.lang.Object onError(Decorated<?> target,
                                java.lang.reflect.Method method,
                                java.lang.Object[] args,
                                java.lang.reflect.InvocationTargetException e)
                         throws java.lang.Throwable

Throws:

java.lang.Throwable

createProxy

protected final <Z> Z createProxy(Decorated<Z> decorated)