GWT perguntas e respostas de entrevista
Pergunta 21. How to work with Server side communication?
Using GWT RPC
To user GWT RPC we need to create couple of interfaces and one implementation class.
1. Synchronous interface
2. Asynchronous interface
3. Implementation class implements Synchronous interface.
Pergunta 22. How are we going to get the response from server side?
For this purpose only GWT has one Asynchronous interface which has one parameter called AsyncCallBack, using this callback object it will call the client side code once the server completed the execution.
So basically all the calls to server side method will have two call back methods
onSuccess()
onFailure()
If the server side method executed properly then onSuccess() method will be called otherwise onFailure() method will be called, so based on this we can proceed with our functionality.
Pergunta 23. How to use RequestBuilder?
To use RequestBuilder we need to inherit HTTP Module in module.xml file
<inherits name="com.google.gwt.http.HTTP"/>
Pergunta 24. What is the purpose of the IsSerializable interface in GWT?
A user-defined class is serializable if all of the following apply:
It is assignable to IsSerializable or Serializable, either because it directly implements one of these interfaces or because it derives from a superclass that does
All non-final, non-transient instance fields are themselves serializable, and
As of GWT 1.5, it must have a default (zero argument) constructor (with any access modifier) or no constructor at all.
One key difference though is that , for security reasons, all Serializable classes must be included in a serialization policy, which is generated at compile time, while IsSerializable classes do not have that requirement.
If your interest is purely in GWT, and you don't e.g. share your model classes between the web application and another application, I suggest you have your model classes/DTOs implement IsSerializable.
Pergunta 25. How GWT Navigation works?
In GWT we can handle page navigation using couple of ways.
1. Using History tokens
2. Clearing the content panel and load the new page in the content panel.
Mais uteis segundo os usuarios:
- What is Google Web Toolkit (GWT)?
- How many modes are provided by GWT to execute application?
- What are Modules, Entry Points and HTML Pages in GWT?
- How can you set Browser targeted Compilation in GWT?
- How can we run GWT application?