/*
* 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.
*/
package org.apache.pdfbox.util;
import java.io.IOException;
import java.util.Iterator;
import java.util.List;
import org.apache.pdfbox.pdmodel.PDDocument;
/**
* Wrap stripped text in simple HTML, trying to form HTML paragraphs. Paragraphs
* broken by pages, columns, or figures are not mended.
*
*
* @author jjb - http://www.johnjbarton.com
* @version $Revision: 1.3 $
*/
public class PDFText2HTML extends PDFTextStripper
{
private static final int INITIAL_PDF_TO_HTML_BYTES = 8192;
private boolean onFirstPage = true;
/**
* Constructor.
* @param encoding The encoding to be used
* @throws IOException If there is an error during initialization.
*/
public PDFText2HTML(String encoding) throws IOException
{
super(encoding);
setLineSeparator(systemLineSeparator);
setParagraphStart("<p>");
setParagraphEnd("</p>"+systemLineSeparator);
setPageStart("<div style=\"page-break-before:always; page-break-after:always\">");
setPageEnd("</div>"+systemLineSeparator);
setArticleStart(systemLineSeparator);
setArticleEnd(systemLineSeparator);
}
/**
* Write the header to the output document. Now also writes the tag defining
* the character encoding.
*
* @throws IOException
* If there is a problem writing out the header to the document.
*/
protected void writeHeader() throws IOException
{
StringBuffer buf = new StringBuffer(INITIAL_PDF_TO_HTML_BYTES);
buf.append("<!DOCTYPE html PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\"" + "\n"
+ "\"http://www.w3.org/TR/html4/loose.dtd\">\n");
buf.append("<html><head>");
buf.append("<title>" + escape(getTitle()) + "</title>\n");
if(outputEncoding != null)
{
buf.append("<meta http-equiv=\"Content-Type\" content=\"text/html; charset="
+ this.outputEncoding + "\">\n");
}
buf.append("</head>\n");
buf.append("<body>\n");
super.writeString(buf.toString());
}
/**
* {@inheritDoc}
*/
protected void writePage() throws IOException
{
if (onFirstPage)
{
writeHeader();
onFirstPage = false;
}
super.writePage();
}
/**
* {@inheritDoc}
*/
public void endDocument(PDDocument pdf) throws IOException
{
super.writeString("</body></html>");
}
/**
* This method will attempt to guess the title of the document using
* either the document properties or the first lines of text.
*
* @return returns the title.
*/
protected String getTitle()
{
String titleGuess = document.getDocumentInformation().getTitle();
if(titleGuess != null && titleGuess.length() > 0)
{
return titleGuess;
}
else
{
Iterator<List<TextPosition>> textIter = getCharactersByArticle().iterator();
float lastFontSize = -1.0f;
StringBuffer titleText = new StringBuffer();
while (textIter.hasNext())
{
Iterator<TextPosition> textByArticle = textIter.next().iterator();
while (textByArticle.hasNext())
{
TextPosition position = textByArticle.next();
float currentFontSize = position.getFontSize();
//If we're past 64 chars we will assume that we're past the title
//64 is arbitrary
if (currentFontSize != lastFontSize || titleText.length() > 64)
{
if (titleText.length() > 0)
{
return titleText.toString();
}
lastFontSize = currentFontSize;
}
if (currentFontSize > 13.0f)
{ // most body text is 12pt
titleText.append(position.getCharacter());
}
}
}
}
return "";
}
/**
* Write out the article separator (div tag) with proper text direction
* information.
*
* @param isltr true if direction of text is left to right
* @throws IOException
* If there is an error writing to the stream.
*/
protected void startArticle(boolean isltr) throws IOException
{
if (isltr)
{
super.writeString("<div>");
}
else
{
super.writeString("<div dir=\"RTL\">");
}
}
/**
* Write out the article separator.
*
* @throws IOException
* If there is an error writing to the stream.
*/
protected void endArticle() throws IOException
{
super.endArticle();
super.writeString("</div>");
}
/**
* Write a string to the output stream and escape some HTML characters.
*
* @param chars String to be written to the stream
* @throws IOException
* If there is an error writing to the stream.
*/
protected void writeString(String chars) throws IOException
{
super.writeString(escape(chars));
}
/**
* Escape some HTML characters.
*
* @param chars String to be escaped
* @return returns escaped String.
*/
private String escape(String chars)
{
StringBuilder builder = new StringBuilder(chars.length());
for (int i = 0; i < chars.length(); i++)
{
char c = chars.charAt(i);
// write non-ASCII as named entities
if ((c < 32) || (c > 126))
{
int charAsInt = c;
builder.append("&#").append(charAsInt).append(";");
}
else
{
switch (c)
{
case 34:
builder.append(""");
break;
case 38:
builder.append("&");
break;
case 60:
builder.append("<");
break;
case 62:
builder.append(">");
break;
default:
builder.append(String.valueOf(c));
}
}
}
return builder.toString();
}
}