# Uses of Interface
org.apache.tiles.request.attribute.HasKeys

Packages that use HasKeys
Package
Description
org.apache.tiles.request.attribute
Methods to get, set and remove attributes from different sources (like HTTP requests or sessions).
org.apache.tiles.request.collection
Special collections and maps for attributes (like HTTP request or session attributes).
org.apache.tiles.request.freemarker.extractor
Extractors to get information from Freemarker objects.
org.apache.tiles.request.jsp.extractor
Extractors to get scopes from `PageContext`.
org.apache.tiles.request.servlet.extractor
Extractors to get attributes and other info from servlet requests and contexts.
org.apache.tiles.request.velocity.extractor
Extractors to get info about Velocity-specific objects.

- ## Uses of HasKeys in org.apache.tiles.request.attribute

  Subinterfaces of HasKeys in org.apache.tiles.request.attribute
  Modifier and Type
  Interface
  Description
  `interface`
  `AttributeExtractor`
  Allows to get, put and remove Object-type attributes.
  `interface`
  `EnumeratedValuesExtractor`
  Allows to get values from multi-valued attributes.
  `interface`
  `HasAddableKeys<V>`
  Allows to get and set attributes.
  `interface`
  `HasRemovableKeys<V>`
  Allows to get and remove attributes.

- ## Uses of HasKeys in org.apache.tiles.request.collection

  Fields in org.apache.tiles.request.collection declared as HasKeys
  Modifier and Type
  Field
  Description
  `protected HasKeys<V>`
  ReadOnlyEnumerationMap.`request`
  The request.
  Constructors in org.apache.tiles.request.collection with parameters of type HasKeys
  Modifier
  Constructor
  Description
  ``
  `KeySet(HasKeys<?> request)`
  Constructor.
  ``
  `ReadOnlyEnumerationMap(HasKeys<V> request)`
  Constructor.

- ## Uses of HasKeys in org.apache.tiles.request.freemarker.extractor

  Classes in org.apache.tiles.request.freemarker.extractor that implement HasKeys
  Modifier and Type
  Class
  Description
  `class`
  `EnvironmentScopeExtractor`
  Extract attributes from `Environment` objects as a scope.

- ## Uses of HasKeys in org.apache.tiles.request.jsp.extractor

  Classes in org.apache.tiles.request.jsp.extractor that implement HasKeys
  Modifier and Type
  Class
  Description
  `class`
  `ScopeExtractor`
  Extracts attributes from a numbered scope from `JspContext`.
  `class`
  `SessionScopeExtractor`
  Extracts attributes from session scope from `PageContext`.

- ## Uses of HasKeys in org.apache.tiles.request.servlet.extractor

  Classes in org.apache.tiles.request.servlet.extractor that implement HasKeys
  Modifier and Type
  Class
  Description
  `class`
  `ApplicationScopeExtractor`
  Extract attributes from application scope.
  `class`
  `HeaderExtractor`
  Extract header values from an HTTP request.
  `class`
  `InitParameterExtractor`
  Extract initialization parameters from the servlet context.
  `class`
  `ParameterExtractor`
  Extract parameters from the request.
  `class`
  `RequestScopeExtractor`
  Extracts attributes from request scope.
  `class`
  `SessionScopeExtractor`
  Extract attributes from session scope.

- ## Uses of HasKeys in org.apache.tiles.request.velocity.extractor

  Classes in org.apache.tiles.request.velocity.extractor that implement HasKeys
  Modifier and Type
  Class
  Description
  `class`
  `VelocityScopeExtractor`
  Extracts attributes from Velocity context..