| /* |
| * Copyright (C) 2007-2010 JĂșlio Vilmar Gesser. |
| * Copyright (C) 2011, 2013-2016 The JavaParser Team. |
| * |
| * This file is part of JavaParser. |
| * |
| * JavaParser can be used either under the terms of |
| * a) the GNU Lesser General Public License as published by |
| * the Free Software Foundation, either version 3 of the License, or |
| * (at your option) any later version. |
| * b) the terms of the Apache License |
| * |
| * You should have received a copy of both licenses in LICENCE.LGPL and |
| * LICENCE.APACHE. Please refer to those files for details. |
| * |
| * JavaParser is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU Lesser General Public License for more details. |
| */ |
| |
| package com.github.javaparser.printer.lexicalpreservation; |
| |
| import java.util.Iterator; |
| import java.util.LinkedList; |
| import java.util.List; |
| |
| class TextElementIteratorsFactory { |
| |
| static class CascadingIterator<E> implements Iterator<E> { |
| interface Provider<E> { |
| Iterator<E> provide(); |
| } |
| |
| private final Provider<E> nextProvider; |
| private Iterator<E> current; |
| private Iterator<E> next; |
| private boolean lastReturnedFromCurrent = false; |
| private boolean lastReturnedFromNext = false; |
| |
| public CascadingIterator(Iterator<E> current, Provider<E> nextProvider) { |
| this.nextProvider = nextProvider; |
| this.current = current; |
| } |
| |
| |
| @Override |
| public boolean hasNext() { |
| if (current.hasNext()) { |
| return true; |
| } |
| if (next == null) { |
| next = nextProvider.provide(); |
| } |
| return next.hasNext(); |
| } |
| |
| @Override |
| public E next() { |
| if (current.hasNext()) { |
| lastReturnedFromCurrent = true; |
| lastReturnedFromNext = false; |
| return current.next(); |
| } |
| if (next == null) { |
| next = nextProvider.provide(); |
| } |
| lastReturnedFromCurrent = false; |
| lastReturnedFromNext = true; |
| return next.next(); |
| } |
| |
| @Override |
| public void remove() { |
| if (lastReturnedFromCurrent) { |
| current.remove(); |
| return; |
| } |
| if (lastReturnedFromNext) { |
| next.remove(); |
| return; |
| } |
| throw new IllegalArgumentException(); |
| } |
| } |
| |
| static class EmptyIterator<E> implements Iterator<E> { |
| @Override |
| public boolean hasNext() { |
| return false; |
| } |
| |
| @Override |
| public E next() { |
| throw new IllegalArgumentException(); |
| } |
| } |
| |
| private static class SingleElementIterator<E> implements Iterator<E> { |
| private final E element; |
| private boolean returned; |
| |
| SingleElementIterator(E element) { |
| this.element = element; |
| } |
| |
| @Override |
| public boolean hasNext() { |
| return !returned; |
| } |
| |
| @Override |
| public E next() { |
| returned = true; |
| return element; |
| } |
| |
| @Override |
| public void remove() { |
| |
| } |
| } |
| |
| static class ComposedIterator<E> implements Iterator<E> { |
| private final List<Iterator<E>> elements; |
| private int currIndex; |
| |
| ComposedIterator(List<Iterator<E>> elements) { |
| this.elements = elements; |
| currIndex = 0; |
| } |
| |
| @Override |
| public boolean hasNext() { |
| if (currIndex >= elements.size()) { |
| return false; |
| } |
| if (elements.get(currIndex).hasNext()){ |
| return true; |
| } |
| currIndex++; |
| return hasNext(); |
| } |
| |
| @Override |
| public E next() { |
| if (!hasNext()) { |
| throw new IllegalArgumentException(); |
| } |
| return elements.get(currIndex).next(); |
| } |
| |
| @Override |
| public void remove() { |
| elements.get(currIndex).remove(); |
| } |
| } |
| |
| private static Iterator<TokenTextElement> reverseIterator(NodeText nodeText, int index) { |
| TextElement textElement = nodeText.getTextElement(index); |
| if (textElement instanceof TokenTextElement) { |
| return new SingleElementIterator<TokenTextElement>((TokenTextElement)textElement) { |
| @Override |
| public void remove() { |
| nodeText.removeElement(index); |
| } |
| }; |
| } else if (textElement instanceof ChildTextElement) { |
| ChildTextElement childTextElement = (ChildTextElement)textElement; |
| NodeText textForChild = childTextElement.getNodeTextForWrappedNode(); |
| return reverseIterator(textForChild); |
| } else { |
| throw new IllegalArgumentException(); |
| } |
| } |
| |
| public static Iterator<TokenTextElement> reverseIterator(NodeText nodeText) { |
| return partialReverseIterator(nodeText, nodeText.numberOfElements() - 1); |
| } |
| |
| public static Iterator<TokenTextElement> partialReverseIterator(NodeText nodeText, int fromIndex) { |
| List<Iterator<TokenTextElement>> elements = new LinkedList<>(); |
| for (int i=fromIndex;i>=0;i--) { |
| elements.add(reverseIterator(nodeText, i)); |
| } |
| return new ComposedIterator<>(elements); |
| } |
| |
| } |