Class ObjectMap

All Implemented Interfaces:
Callable, FunctionItem, GroundedValue, Item, Sequence

public class ObjectMap extends SystemFunction
Extension function saxon:object-map(), which converts an external object to a map

The current implementation physically creates a new map, though there's some optimization if it is known that only one of the entries will be needed. There would be scope for a faster implementation, creating a virtual map backed by the Java object, if this proves to be needed.

Since:
9.9
  • Constructor Details

    • ObjectMap

      public ObjectMap()
  • Method Details

    • call

      public MapItem call(XPathContext context, Sequence[] arguments) throws XPathException
      Evaluate this function call at run-time
      Parameters:
      context - The XPath dynamic evaluation context
      arguments - The values of the arguments to the function call. Each argument value (which is in general a sequence) is supplied in the form of an iterator over the items in the sequence. If required, the supplied sequence can be materialized by calling, for example, new SequenceExtent(arguments[i]). If the argument is always a singleton, then the single item may be obtained by calling arguments[i].next(). The implementation is not obliged to read all the items in each SequenceIterator if they are not required to compute the result; but if any SequenceIterator is not read to completion, it is good practice to call its close() method.
      Returns:
      an iterator over the results of the function. If the result is a single item, it can be returned in the form of a SingletonIterator. If the result is an empty sequence, the method should return EmptyIterator.getInstance()
      Throws:
      XPathException - if a dynamic error occurs during evaluation of the function. The Saxon run-time code will add information about the error location.
    • toMap

      public static MapItem toMap(Configuration config, ObjectValue<?> value, String required)
      Convert a Java object to a map
      Parameters:
      config - the Saxon Configuration
      value - the (wrapped) Java object to be converted
      required - if non-null, indicates the key of the entry that is required in the map. If this parameter is supplied, then the map will be limited to a single entry with this key, since it is known that the other entries would never be used.
      Returns:
      an XDM map containing entries representing the public instance-level methods available in the object, to the extent that they have unique names.
    • makeMethodMap

      public static Map<String,FunctionItem> makeMethodMap(Configuration config, Class<?> javaClass, String required)
      Make a map representing the methods defined in a class. This map is specific to the class, not to a particular instance. The functions present in this map take an extra first argument representing the target instance; the functions returned in the final instance-level map will be partial applications of the functions in the class-level map
      Parameters:
      config - the Saxon configuration
      javaClass - the Java class whose methods are required
      required - if non-null, indicates the key of the entry that is required in the map. If this parameter is supplied, then the map will be limited to a single entry with this key, since it is known that the other entries would never be used
      Returns:
      a map whose entries represent public instance-level methods in the supplied Java class, to the extent that these methods have unique names.