Step.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
* PROPERTY OR OTHERWISE, AND WHETHER OR NOT LOSS WAS SUSTAINED FROM, OR AROSE OUT
* OF THE RESULTS OF, OR USE OF, THE SOFTWARE OR SERVICES PROVIDED HEREUNDER.
*/
package gov.nist.secauto.metaschema.core.metapath;
import gov.nist.secauto.metaschema.core.metapath.item.IItem;
import gov.nist.secauto.metaschema.core.metapath.item.node.INodeItem;
import gov.nist.secauto.metaschema.core.util.ObjectUtils;
import java.util.List;
import edu.umd.cs.findbugs.annotations.NonNull;
/**
* An immutable expression that combines the evaluation of a sub-expression,
* with the evaluation of a series of predicate expressions that filter the
* result of the evaluation.
*/
class Step implements IExpression { // NOPMD - intentional
@NonNull
private final Axis axisExpression;
@NonNull
private final IExpression stepExpression;
@NonNull
private final Class<? extends IItem> staticResultType;
/**
* Construct a new stepExpression expression.
*
* @param axis
* the axis to evaluate against
* @param step
* the sub-expression to evaluate before filtering with the predicates
*/
@SuppressWarnings("null")
protected Step(@NonNull Axis axis, @NonNull IExpression step) {
this.axisExpression = axis;
this.stepExpression = step;
this.staticResultType = ExpressionUtils.analyzeStaticResultType(IItem.class, List.of(step));
}
@NonNull
public Axis getAxis() {
return axisExpression;
}
/**
* Get the stepExpression's sub-expression.
*
* @return the sub-expression
*/
@NonNull
public IExpression getStep() {
return stepExpression;
}
@Override
public Class<? extends IItem> getStaticResultType() {
return staticResultType;
}
@Override
public List<? extends IExpression> getChildren() {
return ObjectUtils.notNull(List.of(getAxis(), getStep()));
}
@Override
public <RESULT, CONTEXT> RESULT accept(IExpressionVisitor<RESULT, CONTEXT> visitor, CONTEXT context) {
return visitor.visitStep(this, context);
}
@Override
public ISequence<?> accept(DynamicContext dynamicContext, ISequence<?> focus) {
ISequence<? extends INodeItem> axisResult = getAxis().accept(dynamicContext, focus);
return getStep().accept(dynamicContext, axisResult);
}
@SuppressWarnings("null")
@Override
public String toASTString() {
return String.format("%s[axis=%s]", getClass().getName(), getAxis().name());
}
}