Module dev.metaschema.core

Package dev.metaschema.core.metapath.function.library

Class FnExactlyOne

java.lang.Object

dev.metaschema.core.metapath.function.library.FnExactlyOne

public final class FnExactlyOne
extends Object

Implements the XPath 3.1 fn:exactly-one function.

Method Summary

Modifier and Type	Method	Description
static ISequence<?>	fnExactlyOne(ISequence<?> sequence)	Check that the provided sequence has exactly one item.

Methods inherited from class java.lang.Object

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

Method Details

fnExactlyOne

@NonNull
public static ISequence<?> fnExactlyOne(@NonNull
 ISequence<?> sequence)

Check that the provided sequence has exactly one item.

Based on the XPath 3.1 fn:exactly-one function.

Parameters:

sequence - the sequence to evaluate

Returns:

the sequence if it has zero or one items

Throws:

InvalidArgumentFunctionException - with the code InvalidArgumentFunctionException.INVALID_ARGUMENT_EXACTLY_ONE if the sequence contains less or more than one item