com.saxonica.functions.extfn

Class ObjectMap

java.lang.Object

net.sf.saxon.functions.AbstractFunction

net.sf.saxon.functions.SystemFunction

com.saxonica.functions.extfn.ObjectMap

All Implemented Interfaces:

java.lang.Iterable<Function>, Callable, Function, GroundedValue<Function>, Item<Function>, Sequence<Function>

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 Summary

Constructors

Constructor and Description
ObjectMap()

Method Summary

Modifier and Type	Method and Description
MapItem	call(XPathContext context, Sequence[] arguments) Evaluate this function call at run-time
static java.util.Map<java.lang.String,Function>	makeMethodMap(Configuration config, java.lang.Class javaClass, java.lang.String required) Make a map representing the methods defined in a class.
static MapItem	toMap(Configuration config, ObjectValue value, java.lang.String required) Convert a Java object to a map

Methods inherited from class net.sf.saxon.functions.SystemFunction

dependsOnContextItem, dynamicCall, equals, export, exportAdditionalArguments, exportAttributes, fixArguments, getArity, getCardinality, getCompilerName, getContextNode, getDescription, getDetails, getErrorCodeForTypeErrors, getFunctionItemType, getFunctionName, getIntegerBounds, getNetCost, getOperandRoles, getRequiredType, getResultItemType, getResultItemType, getRetainedStaticContext, getSpecialProperties, getStaticBaseUriString, getStreamerName, importAttributes, isTrustedResultType, makeCall, makeFunction, makeFunctionCall, makeOptimizedFunctionCall, resultIfEmpty, setArity, setDetails, setRetainedStaticContext, supplyTypeInformation, toShortString, toString, typeCheckCaller

Methods inherited from class net.sf.saxon.functions.AbstractFunction

atomize, deepEquals, effectiveBooleanValue, getAnnotations, getStringValue, getStringValueCS, isArray, isMap, makeNewContext, simplify, typeCheck

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.sf.saxon.om.Function

argumentArray, getGenre

Methods inherited from interface net.sf.saxon.om.Item

getLength, head, isStreamed, itemAt, iterate, iterator, reduce, subsequence, toGroundedValue

Methods inherited from interface net.sf.saxon.om.GroundedValue

asIterable, materialize

Methods inherited from interface net.sf.saxon.om.Sequence

makeRepeatable

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

ObjectMap

public ObjectMap()

Method Detail

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,
                            java.lang.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 java.util.Map<java.lang.String,Function> makeMethodMap(Configuration config,
                                                                     java.lang.Class javaClass,
                                                                     java.lang.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.