Locator (Google Web Toolkit Javadoc)

java.lang.Object
- com.google.web.bindery.requestfactory.shared.Locator<T,I>

Type Parameters:
T - the type of domain object the Locator will operate on
I - the type of object the Locator expects to use as an id for the domain object

Direct Known Subclasses:

ValueLocator
```
public abstract class Locator<T,I>
extends java.lang.Object
```
A Locator allows entity types that do not conform to the RequestFactory entity protocol to be used. Instead of attempting to use a findFoo(), getId(), and getVersion() declared in the domain entity type, an instance of a Locator will be created to provide implementations of these methods.
Locator subtypes must be default instantiable (i.e. public static types with a no-arg constructor). Instances of Locators may be retained and reused by the RequestFactory service layer.

See Also:
ProxyFor.locator()

Constructor Summary

Constructors
Constructor and Description

Locator()

Constructors
Constructor and Description
`Locator()`

Method Summary

Methods
Modifier and Type	Method and Description
`abstract T`	`create(java.lang.Class<? extends T> clazz)` Create a new instance of the requested type.
`abstract T`	`find(java.lang.Class<? extends T> clazz, I id)` Retrieve an object.
`abstract java.lang.Class<T>`	`getDomainType()` Returns the `T` type.
`abstract I`	`getId(T domainObject)` Returns a domain object to be used as the id for the given object.
`abstract java.lang.Class<I>`	`getIdType()` Returns the `I` type.
`abstract java.lang.Object`	`getVersion(T domainObject)` Returns a domain object to be used as the version for the given object.
`boolean`	`isLive(T domainObject)` Returns a value indicating if the domain object should no longer be considered accessible.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - Locator
```
public Locator()
```
- Method Detail
  - create
```
public abstract T create(java.lang.Class<? extends T> clazz)
```
    Create a new instance of the requested type.
    
    Parameters:
    clazz - the type of object to create
    
    Returns:
    the new instance of the domain type
  - find
```
public abstract T find(java.lang.Class<? extends T> clazz,
     I id)
```
    Retrieve an object. May return null to indicate that the requested object could not be found.
    
    Parameters:
    clazz - the type of object to retrieve
    id - an id previously returned from getId(Object)
    
    Returns:
    the requested object or null if it could not be found
  - getDomainType
```
public abstract java.lang.Class<T> getDomainType()
```
    Returns the T type.
  - getId
```
public abstract I getId(T domainObject)
```
    Returns a domain object to be used as the id for the given object. This method may return null if the object has not been persisted or should be treated as irretrievable.
    
    Parameters:
    domainObject - the object to obtain an id for
    
    Returns:
    the object's id or null
  - getIdType
```
public abstract java.lang.Class<I> getIdType()
```
    Returns the I type.
  - getVersion
```
public abstract java.lang.Object getVersion(T domainObject)
```
    Returns a domain object to be used as the version for the given object. This method may return null if the object has not been persisted or should be treated as irretrievable.
    
    Parameters:
    domainObject - the object to obtain an id for
    
    Returns:
    the object's version or null
  - isLive
```
public boolean isLive(T domainObject)
```
    Returns a value indicating if the domain object should no longer be considered accessible. This method might return false if the record underlying the domain object had been deleted as a side-effect of processing a request.
    The default implementation of this method uses getId(Object) and find(Class, Object) to determine if an object can be retrieved.

Class Locator<T,I>

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Locator

Method Detail

create

find

getDomainType

getId

getIdType

getVersion

isLive