com.github.simy4.xpath.expr.PathExpr Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of xpath-to-xml-core Show documentation

Convenient utility to build XML models by evaluating XPath expressions

There is a newer version: 2.3.9

/*
 * Copyright 2017-2021 Alex Simkin
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.github.simy4.xpath.expr;

import com.github.simy4.xpath.XmlBuilderException;
import com.github.simy4.xpath.navigator.Navigator;
import com.github.simy4.xpath.navigator.Node;
import com.github.simy4.xpath.util.Function;
import com.github.simy4.xpath.view.IterableNodeView;
import com.github.simy4.xpath.view.NodeView;

import java.io.Serializable;
import java.util.Iterator;
import java.util.List;

public class PathExpr implements Expr, Serializable {

  private static final long serialVersionUID = 1L;

  private final List pathExpr;

  public PathExpr(List pathExpr) {
    this.pathExpr = pathExpr;
  }

  @Override
  public  IterableNodeView resolve(
      Navigator navigator, NodeView view, boolean greedy) throws XmlBuilderException {
    final boolean newGreedy = !view.hasNext() && greedy;
    IterableNodeView children = view;
    for (final StepExpr stepExpr : pathExpr) {
      children = children.flatMap(new StepResolver(navigator, stepExpr, newGreedy));
    }
    return children;
  }

  @Override
  public String toString() {
    final Iterator pathExprIterator = pathExpr.iterator();
    final StringBuilder stringBuilder = new StringBuilder();
    if (pathExprIterator.hasNext()) {
      stringBuilder.append(pathExprIterator.next());
      while (pathExprIterator.hasNext()) {
        stringBuilder.append('/').append(pathExprIterator.next());
      }
    }
    return stringBuilder.toString();
  }

  private static final class StepResolver
      implements Function, IterableNodeView> {

    private final Navigator navigator;
    private final StepExpr stepExpr;
    private final boolean greedy;

    private StepResolver(Navigator navigator, StepExpr stepExpr, boolean greedy) {
      this.navigator = navigator;
      this.stepExpr = stepExpr;
      this.greedy = greedy;
    }

    @Override
    public IterableNodeView apply(NodeView view) {
      return stepExpr.resolve(navigator, view, greedy);
    }
  }
}