Class GroupExtractor

java.lang.Object
org.simpleframework.xml.core.GroupExtractor
All Implemented Interfaces:
Group
class GroupExtractor extends Object implements Group
The GroupExtractor represents an extractor for labels associated with a particular union annotation. This extractor registers Label by name and by type. Acquiring the label by type allows the serialization process to dynamically select a label, and thus converter, based on the instance type. On deserialization a label is dynamically selected based on name.
See Also:

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    private static class 
    GroupExtractor.Registry
    The Registry object is used to maintain mappings from types to labels.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private final LabelMap
    elements
    This contains each label registered by label name.
    private final ExtractorFactory
    factory
    This represents a factory for creating union extractors.
    private final Annotation
    label
    This represents the union label to be used for this group.
    private final GroupExtractor.Registry
    registry
    This contains each label registered by name and by type.

  • Constructor Summary

    Constructors
    Constructor
    Description
    GroupExtractor(Contact contact, Annotation label, Format format)
    Constructor for the GroupExtractor object.

  • Method Summary

    Modifier and Type
    Method
    Description
    private void
    extract()
    This is used to extract the labels associated with the group.
    private void
    extract(Extractor extractor)
    This is used to extract the labels associated with the group.
    private void
    extract(Extractor extractor, Annotation value)
    This is used to extract the labels associated with the group.
    LabelMap
    getElements()
    This is used to acquire a LabelMap containing the labels available to the group.
    Label
    getLabel(Class type)
    This is used to acquire a Label based on the type of an object.
    String[]
    getNames()
    This is used to acquire the names for each label associated with this Group instance.
    String[]
    getPaths()
    This is used to acquire the paths for each label associated with this Group instance.
    Label
    getText()
    This is used to get a Label that represents the text between elements on an element union.
    boolean
    isDeclared(Class type)
    This is used to determine if a type has been declared by the annotation associated with the group.
    boolean
    isInline()
    This is used to determine if the group is inline.
    boolean
    isTextList()
    This is used to determine if an annotated list is a text list.
    boolean
    isValid(Class type)
    This is used to determine if the associated type represents a label defined within the union group.
    String
    toString()
    This returns a string representation of the union group.

    Methods inherited from class Object

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

  • Field Details

    • factory

      private final ExtractorFactory factory
      This represents a factory for creating union extractors.

    • label

      private final Annotation label
      This represents the union label to be used for this group.

    • registry

      private final GroupExtractor.Registry registry
      This contains each label registered by name and by type.

    • elements

      private final LabelMap elements
      This contains each label registered by label name.

  • Constructor Details

    • GroupExtractor

      public GroupExtractor(Contact contact, Annotation label, Format format) throws Exception
      Constructor for the GroupExtractor object. This will create an extractor for the provided union annotation. Each individual declaration within the union is extracted and made available within the group.
      Parameters:
      contact - this is the annotated field or method
      label - this is the label associated with the contact
      format - this is the format used by this extractor
      Throws:
      Exception

  • Method Details

    • getNames

      public String[] getNames() throws Exception
      This is used to acquire the names for each label associated with this Group instance. The names provided here are not styled according to a serialization context.
      Returns:
      this returns the names of each union extracted
      Throws:
      Exception

    • getPaths

      public String[] getPaths() throws Exception
      This is used to acquire the paths for each label associated with this Group instance. The paths provided here are not styled according to a serialization context.
      Returns:
      this returns the paths of each union extracted
      Throws:
      Exception

    • getElements

      public LabelMap getElements() throws Exception
      This is used to acquire a LabelMap containing the labels available to the group. Providing a context object ensures that each of the labels is mapped to a name that is styled according to its internal style.
      Specified by:
      getElements in interface Group
      Returns:
      this returns a label map containing the labels
      Throws:
      Exception

    • getLabel

      public Label getLabel(Class type)
      This is used to acquire a Label based on the type of an object. Selecting a label based on the type ensures that the serialization process can dynamically convert an object to XML. If the type is not supported, this returns null.
      Specified by:
      getLabel in interface Group
      Parameters:
      type - this is the type to select the label from
      Returns:
      this returns the label based on the type

    • getText

      public Label getText()
      This is used to get a Label that represents the text between elements on an element union. Providing a label here ensures that the free text found between elements can be converted in to strings and added to the list.
      Specified by:
      getText in interface Group
      Returns:
      a label if a text annotation has been declared

    • isValid

      public boolean isValid(Class type)
      This is used to determine if the associated type represents a label defined within the union group. If the label exists this returns true, if not then this returns false.
      Parameters:
      type - this is the type to check for
      Returns:
      this returns true if a label for the type exists

    • isDeclared

      public boolean isDeclared(Class type)
      This is used to determine if a type has been declared by the annotation associated with the group. Unlike determining if the type is valid this will not consider super types.
      Parameters:
      type - this is the type to determine if it is declared
      Returns:
      this returns true if the type has been declared

    • isInline

      public boolean isInline()
      This is used to determine if the group is inline. A group is inline if all of the elements in the group is inline. If any of the Label objects in the group is not inline then the entire group is not inline, although this is unlikely.
      Specified by:
      isInline in interface Group
      Returns:
      this returns true if each label in the group is inline

    • isTextList

      public boolean isTextList()
      This is used to determine if an annotated list is a text list. A text list is a list of elements that also accepts free text. Typically this will be an element list union that will allow unstructured XML such as XHTML to be parsed.
      Specified by:
      isTextList in interface Group
      Returns:
      returns true if the label represents a text list

    • extract

      private void extract() throws Exception
      This is used to extract the labels associated with the group. Extraction will instantiate a Label object for an individual annotation declared within the union. Each of the label instances is then registered by both name and type.
      Throws:
      Exception

    • extract

      private void extract(Extractor extractor) throws Exception
      This is used to extract the labels associated with the group. Extraction will instantiate a Label object for an individual annotation declared within the union. Each of the label instances is then registered by both name and type.
      Parameters:
      extractor - this is the extractor to get labels for
      Throws:
      Exception

    • extract

      private void extract(Extractor extractor, Annotation value) throws Exception
      This is used to extract the labels associated with the group. Extraction will instantiate a Label object for an individual annotation declared within the union. Each of the label instances is then registered by both name and type.
      Parameters:
      extractor - this is the extractor to get labels for
      value - this is an individual annotation declared
      Throws:
      Exception

    • toString

      public String toString()
      This returns a string representation of the union group. Providing a string representation in this way ensures that the group can be used in exception messages and for any debugging.
      Specified by:
      toString in interface Group
      Overrides:
      toString in class Object
      Returns:
      this returns a string representation of the group