/************************************************************************
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* Copyright 2009 IBM. All rights reserved.
*
* Use is subject to license terms.
*
* 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. You can also
* obtain a copy of the License at http://odftoolkit.org/docs/license.txt
*
* 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 org.odftoolkit.odfdom.incubator.doc.text;
import org.odftoolkit.odfdom.dom.DefaultElementVisitor;
import org.odftoolkit.odfdom.dom.OdfDocumentNamespace;
import org.odftoolkit.odfdom.dom.element.text.TextHElement;
import org.odftoolkit.odfdom.dom.element.text.TextLineBreakElement;
import org.odftoolkit.odfdom.dom.element.text.TextPElement;
import org.odftoolkit.odfdom.dom.element.text.TextSElement;
import org.odftoolkit.odfdom.dom.element.text.TextTabElement;
import org.odftoolkit.odfdom.pkg.OdfElement;
import org.w3c.dom.Node;
/**
* It's a sub class of DefaultElementVisitor. It provides a method to get the display text
* of a single element.
* <p> If you pass the content root as the parameter, the whole document content will be
* returned, without any tag information.</p>
* <p> It implements part of white space handling fuctions: text:p, text:h, text:s, text:tab, text:linebreak are processed
* according to ODF specification.</p>
*/
public class OdfTextExtractor extends DefaultElementVisitor {
protected StringBuilder mTextBuilder;
OdfElement mElement;
protected static final char NewLineChar = '\r';
protected static final char TabChar = '\t';
/**
* Default constructor
*/
protected OdfTextExtractor() {
}
/**
* Constructor with an ODF element as paramter
* @param element the ODF element whose text would be extracted.
*/
protected OdfTextExtractor(OdfElement element) {
mTextBuilder = new StringBuilder();
mElement = element;
}
/**
* Append the text content of this element to string buffer.
* @param ele the ODF element whose text will be appended.
*/
protected void appendElementText(OdfElement ele) {
Node node = ele.getFirstChild();
while (node != null) {
if (node.getNodeType() == Node.TEXT_NODE) {
mTextBuilder.append(node.getNodeValue());
} else if (node.getNodeType() == Node.ELEMENT_NODE) {
OdfElement element = (OdfElement) node;
element.accept(this);
}
node = node.getNextSibling();
}
}
/**
* An instance of OdfTextExtractor will be created to
* extract the text content of an ODF element.
* @param element the ODF element whose text will be extracted.
* @return An instance of OdfTextExtractor
*/
public static OdfTextExtractor newOdfTextExtractor(OdfElement element) {
return new OdfTextExtractor(element);
}
/* (non-Javadoc)
* @see org.odftoolkit.odfdom.dom.DefaultElementVisitor#visit(org.odftoolkit.odfdom.pkg.OdfElement)
*/
@Override
public void visit(OdfElement element) {
if (element.getNamespaceURI().equals(OdfDocumentNamespace.META.getUri())
|| element.getNamespaceURI().equals(OdfDocumentNamespace.DC.getUri())) {
mTextBuilder.append(NewLineChar);
}
appendElementText(element);
}
/* (non-Javadoc)
* @see org.odftoolkit.odfdom.dom.DefaultElementVisitor#visit(org.odftoolkit.odfdom.dom.element.text.TextPElement)
*/
@Override
public void visit(TextPElement ele) {
mTextBuilder.append(NewLineChar);
appendElementText(ele);
}
/* (non-Javadoc)
* @see org.odftoolkit.odfdom.dom.DefaultElementVisitor#visit(org.odftoolkit.odfdom.dom.element.text.TextHElement)
*/
@Override
public void visit(TextHElement ele) {
mTextBuilder.append(NewLineChar);
appendElementText(ele);
}
/* (non-Javadoc)
* @see org.odftoolkit.odfdom.dom.DefaultElementVisitor#visit(org.odftoolkit.odfdom.dom.element.text.TextSElement)
*/
@Override
public void visit(TextSElement ele) {
Integer count = ele.getTextCAttribute();
if (count == null) {
count = 1;
}
for (int i = 0; i < count; i++) {
mTextBuilder.append(' ');
}
}
/* (non-Javadoc)
* @see org.odftoolkit.odfdom.dom.DefaultElementVisitor#visit(org.odftoolkit.odfdom.dom.element.text.TextTabElement)
*/
@Override
public void visit(TextTabElement ele) {
mTextBuilder.append(TabChar);
}
/* (non-Javadoc)
* @see org.odftoolkit.odfdom.dom.DefaultElementVisitor#visit(org.odftoolkit.odfdom.dom.element.text.TextLineBreakElement)
*/
@Override
public void visit(TextLineBreakElement ele) {
mTextBuilder.append(NewLineChar);
appendElementText(ele);
}
/**
* Return the text content as a string
* @return the text content as a string
*/
public String getText() {
visit(mElement);
return mTextBuilder.toString();
}
}