CastFunction.java
/*
* Portions of this software was developed by employees of the National Institute
* of Standards and Technology (NIST), an agency of the Federal Government and is
* being made available as a public service. Pursuant to title 17 United States
* Code Section 105, works of NIST employees are not subject to copyright
* protection in the United States. This software may be subject to foreign
* copyright. Permission in the United States and in foreign countries, to the
* extent that NIST may hold copyright, to use, copy, modify, create derivative
* works, and distribute this software and its documentation without fee is hereby
* granted on a non-exclusive basis, provided that this notice and disclaimer
* of warranty appears in all copies.
*
* THE SOFTWARE IS PROVIDED 'AS IS' WITHOUT ANY WARRANTY OF ANY KIND, EITHER
* EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY
* THAT THE SOFTWARE WILL CONFORM TO SPECIFICATIONS, ANY IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND FREEDOM FROM
* INFRINGEMENT, AND ANY WARRANTY THAT THE DOCUMENTATION WILL CONFORM TO THE
* SOFTWARE, OR ANY WARRANTY THAT THE SOFTWARE WILL BE ERROR FREE. IN NO EVENT
* SHALL NIST BE LIABLE FOR ANY DAMAGES, INCLUDING, BUT NOT LIMITED TO, DIRECT,
* INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES, ARISING OUT OF, RESULTING FROM,
* OR IN ANY WAY CONNECTED WITH THIS SOFTWARE, WHETHER OR NOT BASED UPON WARRANTY,
* CONTRACT, TORT, OR OTHERWISE, WHETHER OR NOT INJURY WAS SUSTAINED BY PERSONS OR
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* OF THE RESULTS OF, OR USE OF, THE SOFTWARE OR SERVICES PROVIDED HEREUNDER.
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package gov.nist.secauto.metaschema.core.metapath.function.library;
import gov.nist.secauto.metaschema.core.metapath.DynamicContext;
import gov.nist.secauto.metaschema.core.metapath.ISequence;
import gov.nist.secauto.metaschema.core.metapath.function.FunctionUtils;
import gov.nist.secauto.metaschema.core.metapath.function.IArgument;
import gov.nist.secauto.metaschema.core.metapath.function.IFunction;
import gov.nist.secauto.metaschema.core.metapath.function.IFunctionExecutor;
import gov.nist.secauto.metaschema.core.metapath.item.IItem;
import gov.nist.secauto.metaschema.core.metapath.item.atomic.IAnyAtomicItem;
import gov.nist.secauto.metaschema.core.util.ObjectUtils;
import java.net.URI;
import java.util.List;
import edu.umd.cs.findbugs.annotations.NonNull;
public final class CastFunction<ITEM extends IAnyAtomicItem> implements IFunctionExecutor {
@NonNull
private final ICastExecutor<ITEM> castExecutor;
@NonNull
static <ITEM extends IAnyAtomicItem> IFunction signature(
@NonNull URI namespace,
@NonNull String name,
@NonNull Class<ITEM> resulingAtomicType,
@NonNull ICastExecutor<ITEM> executor) {
return signature(
ObjectUtils.notNull(namespace.toASCIIString()),
name,
resulingAtomicType,
executor);
}
@NonNull
static <ITEM extends IAnyAtomicItem> IFunction signature(
@NonNull String namespace,
@NonNull String name,
@NonNull Class<ITEM> resulingAtomicType,
@NonNull ICastExecutor<ITEM> executor) {
return IFunction.builder()
.name(name)
.namespace(namespace)
.argument(IArgument.newBuilder()
.name("arg1")
.type(IAnyAtomicItem.class)
.zeroOrOne()
.build())
.returnType(resulingAtomicType)
.returnZeroOrOne()
.functionHandler(newCastExecutor(executor))
.build();
}
@NonNull
private static <ITEM extends IAnyAtomicItem> CastFunction<ITEM>
newCastExecutor(@NonNull ICastExecutor<ITEM> executor) {
return new CastFunction<>(executor);
}
private CastFunction(@NonNull ICastExecutor<ITEM> castExecutor) {
this.castExecutor = castExecutor;
}
@Override
public ISequence<ITEM> execute(@NonNull IFunction function,
@NonNull List<ISequence<?>> arguments,
@NonNull DynamicContext dynamicContext,
IItem focus) {
ISequence<? extends IAnyAtomicItem> arg = FunctionUtils.asType(
ObjectUtils.notNull(arguments.get(0)));
IAnyAtomicItem item = FunctionUtils.getFirstItem(arg, true);
if (item == null) {
return ISequence.empty(); // NOPMD - readability
}
ITEM castItem = castExecutor.cast(item);
return ISequence.of(castItem);
}
@FunctionalInterface
public interface ICastExecutor<ITEM extends IAnyAtomicItem> {
/**
* Cast the provided {@code item}.
*
* @param item
* the item to cast
* @return the item cast to the appropriate type
*/
@NonNull
ITEM cast(@NonNull IAnyAtomicItem item);
}
}