Package com.google.web.bindery.requestfactory.server

Class ServiceLayerDecorator

java.lang.Object
com.google.web.bindery.requestfactory.server.ServiceLayer
com.google.web.bindery.requestfactory.server.ServiceLayerDecorator
Direct Known Subclasses:
FindServiceLayer, LocatorServiceLayer, ReflectiveServiceLayer, ResolverServiceLayer, ServiceLayerCache
public class ServiceLayerDecorator extends ServiceLayer
Users that intend to alter how RequestFactory interacts with the domain environment can extend this type and provide it to ServiceLayer.create(ServiceLayerDecorator...). The methods defined in this type will automatically delegate to the next decorator or the root service object after being processed bycreate().

  • Field Details

    • next

      ServiceLayer next
      A pointer to the next deepest layer.

  • Constructor Details

    • ServiceLayerDecorator

      public ServiceLayerDecorator()

  • Method Details

    • createDomainObject

      public <T> T createDomainObject(Class<T> clazz)
      Description copied from class: ServiceLayer
      Create an instance of the requested domain type.
      Specified by:
      createDomainObject in class ServiceLayer
      Type Parameters:
      T - the requested domain type
      Parameters:
      clazz - the requested domain type
      Returns:
      an instance of the requested domain type

    • createLocator

      public <T extends Locator<?, ?>> T createLocator(Class<T> clazz)
      Description copied from class: ServiceLayer
      Create an instance of the requested Locator type.
      Specified by:
      createLocator in class ServiceLayer
      Type Parameters:
      T - the requested Locator type
      Parameters:
      clazz - the requested Locator type
      Returns:
      an instance of the requested Locator type

    • createServiceInstance

      public Object createServiceInstance(Class<? extends RequestContext> requestContext)
      Description copied from class: ServiceLayer
      Create an instance of a service object that can be used as the target for the given method invocation.
      Specified by:
      createServiceInstance in class ServiceLayer
      Parameters:
      requestContext - the RequestContext type for which a service object must be instantiated.
      Returns:
      an instance of the requested service object

    • createServiceLocator

      public <T extends ServiceLocator> T createServiceLocator(Class<T> clazz)
      Description copied from class: ServiceLayer
      Create an instance of the requested ServiceLocator type.
      Specified by:
      createServiceLocator in class ServiceLayer
      Type Parameters:
      T - the requested ServiceLocator type
      Parameters:
      clazz - the requested ServiceLocator type
      Returns:
      an instance of the requested ServiceLocator type

    • getDomainClassLoader

      public ClassLoader getDomainClassLoader()
      Description copied from class: ServiceLayer
      Returns the ClassLoader that should be used when attempting to access domain classes or resources.

      The default implementation returns Thread.currentThread().getContextClassLoader().

      Specified by:
      getDomainClassLoader in class ServiceLayer

    • getGetter

      public Method getGetter(Class<?> domainType, String property)
      Description copied from class: ServiceLayer
      Determine the method to invoke when retrieving the given property.
      Specified by:
      getGetter in class ServiceLayer
      Parameters:
      domainType - a domain entity type
      property - the name of the property to be retrieved
      Returns:
      the Method that should be invoked to retrieve the property or null if the method could not be located

    • getId

      public Object getId(Object domainObject)
      Description copied from class: ServiceLayer
      Return the persistent id for a domain object. May return null to indicate that the domain object has not been persisted. The value returned from this method must be a simple type (e.g. Integer, String) or a domain type for which a mapping to an EntityProxy or Value proxy exists.

      The values returned from this method may be passed to ServiceLayer.loadDomainObject(Class, Object) in the future.

      Specified by:
      getId in class ServiceLayer
      Parameters:
      domainObject - a domain object
      Returns:
      the persistent id of the domain object or null if the object is not persistent

    • getIdType

      public Class<?> getIdType(Class<?> domainType)
      Description copied from class: ServiceLayer
      Returns the type of object the domain type's findFoo() or Locator.getId() expects to receive.
      Specified by:
      getIdType in class ServiceLayer
      Parameters:
      domainType - a domain entity type
      Returns:
      the type of the persistent id value used to represent the domain type

    • getProperty

      public Object getProperty(Object domainObject, String property)
      Description copied from class: ServiceLayer
      Retrieve the named property from the domain object.
      Specified by:
      getProperty in class ServiceLayer
      Parameters:
      domainObject - the domain object being examined
      property - the property name
      Returns:
      the value of the property

    • getRequestReturnType

      public Type getRequestReturnType(Method contextMethod)
      Description copied from class: ServiceLayer
      Compute the return type for a method declared in a RequestContext by analyzing the generic method declaration.
      Specified by:
      getRequestReturnType in class ServiceLayer

    • getSetter

      public Method getSetter(Class<?> domainType, String property)
      Description copied from class: ServiceLayer
      Determine the method to invoke when setting the given property.
      Specified by:
      getSetter in class ServiceLayer
      Parameters:
      domainType - a domain entity type
      property - the name of the property to be set
      Returns:
      the Method that should be invoked to set the property or null if the method could not be located

    • getVersion

      public Object getVersion(Object domainObject)
      Description copied from class: ServiceLayer
      May return null to indicate that the domain object has not been persisted. The value returned from this method must be a simple type (e.g. Integer, String) or a domain type for which a mapping to an EntityProxy or Value proxy exists.
      Specified by:
      getVersion in class ServiceLayer
      Parameters:
      domainObject - a domain object
      Returns:
      the version of the domain object or null if the object is not persistent

    • invoke

      public Object invoke(Method domainMethod, Object... args)
      Description copied from class: ServiceLayer
      Invoke a domain service method. The underlying eventually calls Method.invoke(Object, Object...).
      Specified by:
      invoke in class ServiceLayer
      Parameters:
      domainMethod - the method to invoke
      args - the arguments to pass to the method
      Returns:
      the value returned from the method invocation

    • isLive

      public boolean isLive(Object domainObject)
      Description copied from class: ServiceLayer
      Returns true if the given domain object is still live (i.e. not deleted) in the backing store.
      Specified by:
      isLive in class ServiceLayer
      Parameters:
      domainObject - a domain entity
      Returns:
      true if domainObject could be retrieved at a later point in time

    • loadDomainObject

      public <T> T loadDomainObject(Class<T> clazz, Object domainId)
      Description copied from class: ServiceLayer
      Load an object from the backing store. This method may return null to indicate that the requested object is no longer available.
      Specified by:
      loadDomainObject in class ServiceLayer
      Type Parameters:
      T - the type of object to load
      Parameters:
      clazz - the type of object to load
      domainId - an id previously returned from ServiceLayer.getId(Object)
      Returns:
      the requested object or null if it is irretrievable

    • loadDomainObjects

      public List<Object> loadDomainObjects(List<Class<?>> classes, List<Object> domainIds)
      Description copied from class: ServiceLayer
      Load multiple objects from the backing store. This method is intended to allow more efficient access to the backing store by providing all objects referenced in an incoming payload.

      The default implementation of this method will delegate to ServiceLayer.loadDomainObject(Class, Object).

      Specified by:
      loadDomainObjects in class ServiceLayer
      Parameters:
      classes - type type of each object to load
      domainIds - the ids previously returned from ServiceLayer.getId(Object)
      Returns:
      the requested objects, elements of which may be null if the requested objects were irretrievable

    • requiresServiceLocator

      public boolean requiresServiceLocator(Method contextMethod, Method domainMethod)
      Description copied from class: ServiceLayer
      Determines if the invocation of a domain method requires a ServiceLocator as the 0th parameter when passed into ServiceLayer.invoke(Method, Object...).
      Specified by:
      requiresServiceLocator in class ServiceLayer
      Parameters:
      contextMethod - a method defined in a RequestContext
      domainMethod - a domain method
      Returns:
      true if a ServiceLocator is required

    • resolveClass

      public Class<? extends BaseProxy> resolveClass(String typeToken)
      Description copied from class: ServiceLayer
      Given a type token previously returned from ServiceLayer.resolveTypeToken(Class), return the Class literal associated with the token.
      Specified by:
      resolveClass in class ServiceLayer
      Parameters:
      typeToken - a string token
      Returns:
      the type represented by the token

    • resolveClientType

      public <T> Class<? extends T> resolveClientType(Class<?> domainClass, Class<T> clientType, boolean required)
      Description copied from class: ServiceLayer
      Determine the type used by the client code to represent a given domain type. If multiple proxy types have been mapped to the same domain type, the clientType parameter is used to ensure assignability.
      Specified by:
      resolveClientType in class ServiceLayer
      Parameters:
      domainClass - the server-side type to be transported to the client
      clientType - the type to which the returned type must be assignable
      required - if true and no mapping is available, throw an exception, otherwise the method will return null
      Returns:
      a class that represents domainClass on the client which is assignable to clientType

    • resolveDomainClass

      public Class<?> resolveDomainClass(Class<?> clazz)
      Description copied from class: ServiceLayer
      Determine the domain (server-side) type that the given client type is mapped to.
      Specified by:
      resolveDomainClass in class ServiceLayer
      Parameters:
      clazz - a client-side type
      Returns:
      the domain type that clientType represents

    • resolveDomainMethod

      public Method resolveDomainMethod(String operation)
      Description copied from class: ServiceLayer
      Return the domain service method associated with a RequestContext method declaration. The requestContextMethod will have been previously resolved by #resolveRequestContextMethod(String, String).
      Specified by:
      resolveDomainMethod in class ServiceLayer
      Returns:
      the domain service method that should be invoked

    • resolveLocator

      public Class<? extends Locator<?,?>> resolveLocator(Class<?> domainType)
      Description copied from class: ServiceLayer
      Return the type of Locator that should be used to access the given domain type.
      Specified by:
      resolveLocator in class ServiceLayer
      Parameters:
      domainType - a domain (server-side) type
      Returns:
      the type of Locator to use, or null if the type conforms to the RequestFactory entity protocol

    • resolveRequestContext

      public Class<? extends RequestContext> resolveRequestContext(String operation)
      Description copied from class: ServiceLayer
      Find a RequestContext that should be used to fulfill the requested operation.
      Specified by:
      resolveRequestContext in class ServiceLayer
      Parameters:
      operation - the operation
      Returns:
      the RequestContext or null if no RequestContext exists that can fulfill the operation

    • resolveRequestContextMethod

      public Method resolveRequestContextMethod(String operation)
      Description copied from class: ServiceLayer
      Find a RequestContext method declaration by name.
      Specified by:
      resolveRequestContextMethod in class ServiceLayer
      Parameters:
      operation - the operation's name
      Returns:
      the method declaration, or null if the method does not exist

    • resolveRequestFactory

      public Class<? extends RequestFactory> resolveRequestFactory(String binaryName)
      Description copied from class: ServiceLayer
      Loads and validates a RequestFactory interface.
      Specified by:
      resolveRequestFactory in class ServiceLayer
      Parameters:
      binaryName - the RequestFactory's type token (usually the type's binary name)
      Returns:
      the RequestFactory type

    • resolveServiceClass

      public Class<?> resolveServiceClass(Class<? extends RequestContext> requestContextClass)
      Description copied from class: ServiceLayer
      Given a RequestContext method, find the service class referenced in the Service or ServiceName annotation.
      Specified by:
      resolveServiceClass in class ServiceLayer
      Parameters:
      requestContextClass - a RequestContext interface
      Returns:
      the type of service to use

    • resolveServiceLocator

      public Class<? extends ServiceLocator> resolveServiceLocator(Class<? extends RequestContext> requestContext)
      Description copied from class: ServiceLayer
      Given a RequestContext method declaration, resolve the ServiceLocator that should be used when invoking the domain method. This method will only be called if ServiceLayer.requiresServiceLocator(Method, Method) returned true for the associated domain method.
      Specified by:
      resolveServiceLocator in class ServiceLayer
      Parameters:
      requestContext - the RequestContext for which a ServiceLocator must be located
      Returns:
      the type of ServiceLocator to use

    • resolveTypeToken

      public String resolveTypeToken(Class<? extends BaseProxy> proxyType)
      Description copied from class: ServiceLayer
      Return a string used to represent the given type in the wire protocol.
      Specified by:
      resolveTypeToken in class ServiceLayer
      Parameters:
      proxyType - a client-side EntityProxy or ValueProxy type
      Returns:
      the type token used to represent the proxy type

    • setProperty

      public void setProperty(Object domainObject, String property, Class<?> expectedType, Object value)
      Description copied from class: ServiceLayer
      Sets a property on a domain object.
      Specified by:
      setProperty in class ServiceLayer
      Parameters:
      domainObject - the domain object to operate on
      property - the name of the property to set
      expectedType - the type of the property
      value - the new value

    • validate

      public <T> Set<ConstraintViolation<T>> validate(T domainObject)
      Description copied from class: ServiceLayer
      Invoke a JSR 303 validator on the given domain object. If no validator is available, this method is a no-op.
      Specified by:
      validate in class ServiceLayer
      Type Parameters:
      T - the type of data being validated
      Parameters:
      domainObject - the domain objcet to validate
      Returns:
      the violations associated with the domain object

    • die

      protected final <T> T die(Throwable e, String message, Object... args) throws UnexpectedException
      Throw a fatal error up into the top-level processing code. This method should be used to provide diagnostic information that will help the end-developer track down problems when that data would expose implementation details of the server to the client.
      Parameters:
      e - a throwable with more data, may be null
      message - a printf-style format string
      args - arguments for the message
      Throws:
      UnexpectedException - this method never returns normally
      See Also:

    • getTop

      protected final ServiceLayer getTop()
      Returns the top-most service layer. General-purpose ServiceLayer decorators should use the instance provided by getTop() when calling public methods on the ServiceLayer API to allow higher-level decorators to override behaviors built into lower-level decorators.
      Returns:
      the ServiceLayer returned by ServiceLayer.create(ServiceLayerDecorator...)

    • report

      protected final <T> T report(InvocationTargetException userGeneratedException) throws ReportableException
      Report an exception thrown by code that is under the control of the end-developer.
      Parameters:
      userGeneratedException - an InvocationTargetException thrown by an invocation of user-provided code
      Throws:
      ReportableException - this method never returns normally

    • report

      protected final <T> T report(String msg, Object... args) throws ReportableException
      Return a message to the client. This method should not include any data that was not sent to the server by the client to avoid leaking data.
      Parameters:
      msg - a printf-style format string
      args - arguments for the message
      Throws:
      ReportableException - this method never returns normally
      See Also:

    • getNext

      final ServiceLayer getNext()
      Retrieves the next service layer. Used only by the server-package code and accessed by used code via super.doSomething().