org.apache.fop.render.rtf.rtflib.rtfdoc.RtfSpaceManager Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
/* $Id: RtfSpaceManager.java 1761020 2016-09-16 11:17:35Z ssteiner $ */
package org.apache.fop.render.rtf.rtflib.rtfdoc;
import java.util.LinkedList;
/**
* This class is responsible for saving space-before/space-after attributes
* history and adding spacing to established candidates (i.e. attributes) or
* accumulation spacing in case of candidate absence.
*/
public class RtfSpaceManager {
/** Stack for saving rtf block-level attributes. */
private LinkedList blockAttributes = new LinkedList();
/** Stack for saving rtf inline-level attributes. */
private LinkedList inlineAttributes = new LinkedList();
/**
* Keeps value of accumulated space in twips. For example if block has
* nonzero space-before or space-after properties and has no plain text
* inside, then the next block should has increased value of space-before
* property.
*/
private int accumulatedSpace;
/**
* Construct a newly allocated RtfSpaceManager object.
*/
public RtfSpaceManager() {
}
/**
* Iterates block-level stack (i.e. all open blocks) and stops updating
* candidate for adding space-before/space-after attribute in case of
* candidate presence.
*/
public void stopUpdatingSpaceBefore() {
for (Object blockAttribute : blockAttributes) {
RtfSpaceSplitter splitter = (RtfSpaceSplitter) blockAttribute;
if (splitter.isBeforeCadidateSet()) {
splitter.stopUpdatingSpaceBefore();
}
}
}
/**
* Set attributes as candidate for space attributes inheritance.
*
* @param attrs attributes to set
*/
public void setCandidate(RtfAttributes attrs) {
for (Object blockAttribute : blockAttributes) {
RtfSpaceSplitter splitter = (RtfSpaceSplitter) blockAttribute;
splitter.setSpaceBeforeCandidate(attrs);
splitter.setSpaceAfterCandidate(attrs);
}
}
/**
* Builds RtfSpaceSplitter on attrs and adds it to the
* block-level stack.
*
* @param attrs RtfAttribute to add
* @return instance of RtfSpaceSplitter
*/
public RtfSpaceSplitter pushRtfSpaceSplitter(RtfAttributes attrs) {
RtfSpaceSplitter splitter;
splitter = new RtfSpaceSplitter(attrs, accumulatedSpace);
// set accumulatedSpace to 0, because now accumulatedSpace used
// in splitter
accumulatedSpace = 0;
blockAttributes.addLast(splitter);
return splitter;
}
/**
* Removes RtfSpaceSplitter from top of block-level stack.
*/
public void popRtfSpaceSplitter() {
if (!blockAttributes.isEmpty()) {
RtfSpaceSplitter splitter;
splitter = (RtfSpaceSplitter) blockAttributes.removeLast();
accumulatedSpace += splitter.flush();
}
}
/**
* Pushes inline attributes to inline-level stack.
*
* @param attrs attributes to add
*/
public void pushInlineAttributes(RtfAttributes attrs) {
inlineAttributes.addLast(attrs);
}
/**
* Pops inline attributes from inline-level stack.
*/
public void popInlineAttributes() {
if (!inlineAttributes.isEmpty()) {
inlineAttributes.removeLast();
}
}
/**
* Peeks at inline-level attribute stack.
*
* @return RtfAttributes from top of inline-level stack
*/
public RtfAttributes getLastInlineAttribute() {
return (RtfAttributes) inlineAttributes.getLast();
}
}