/*
* $Id: PdfContentParser.java 4784 2011-03-15 08:33:00Z blowagie $
*
* This file is part of the iText (R) project.
* Copyright (c) 1998-2011 1T3XT BVBA
* Authors: Bruno Lowagie, Paulo Soares, et al.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License version 3
* as published by the Free Software Foundation with the addition of the
* following permission added to Section 15 as permitted in Section 7(a):
* FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY 1T3XT,
* 1T3XT DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS.
*
* This program 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 Affero General Public License for more details.
* You should have received a copy of the GNU Affero General Public License
* along with this program; if not, see http://www.gnu.org/licenses or write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA, 02110-1301 USA, or download the license from the following URL:
* http://itextpdf.com/terms-of-use/
*
* The interactive user interfaces in modified source and object code versions
* of this program must display Appropriate Legal Notices, as required under
* Section 5 of the GNU Affero General Public License.
*
* In accordance with Section 7(b) of the GNU Affero General Public License,
* a covered work must retain the producer line in every PDF that is created
* or manipulated using iText.
*
* You can be released from the requirements of the license by purchasing
* a commercial license. Buying such a license is mandatory as soon as you
* develop commercial activities involving the iText software without
* disclosing the source code of your own applications.
* These activities include: offering paid services to customers as an ASP,
* serving PDFs on the fly in a web application, shipping iText with a closed
* source product.
*
* For more information, please contact iText Software Corp. at this
* address: [email protected]
*/
package com.itextpdf.text.pdf;
import java.io.IOException;
import java.util.ArrayList;
import com.itextpdf.text.error_messages.MessageLocalization;
import com.itextpdf.text.pdf.PRTokeniser.TokenType;
/**
* Parses the page or template content.
* @author Paulo Soares
*/
public class PdfContentParser {
/**
* Commands have this type.
*/
public static final int COMMAND_TYPE = 200;
/**
* Holds value of property tokeniser.
*/
private PRTokeniser tokeniser;
/**
* Creates a new instance of PdfContentParser
* @param tokeniser the tokeniser with the content
*/
public PdfContentParser(PRTokeniser tokeniser) {
this.tokeniser = tokeniser;
}
/**
* Parses a single command from the content. Each command is output as an array of arguments
* having the command itself as the last element. The returned array will be empty if the
* end of content was reached.
* @param ls an <CODE>ArrayList</CODE> to use. It will be cleared before using. If it's
* <CODE>null</CODE> will create a new <CODE>ArrayList</CODE>
* @return the same <CODE>ArrayList</CODE> given as argument or a new one
* @throws IOException on error
*/
public ArrayList<PdfObject> parse(ArrayList<PdfObject> ls) throws IOException {
if (ls == null)
ls = new ArrayList<PdfObject>();
else
ls.clear();
PdfObject ob = null;
while ((ob = readPRObject()) != null) {
ls.add(ob);
if (ob.type() == COMMAND_TYPE)
break;
}
return ls;
}
/**
* Gets the tokeniser.
* @return the tokeniser.
*/
public PRTokeniser getTokeniser() {
return this.tokeniser;
}
/**
* Sets the tokeniser.
* @param tokeniser the tokeniser
*/
public void setTokeniser(PRTokeniser tokeniser) {
this.tokeniser = tokeniser;
}
/**
* Reads a dictionary. The tokeniser must be positioned past the "<<" token.
* @return the dictionary
* @throws IOException on error
*/
public PdfDictionary readDictionary() throws IOException {
PdfDictionary dic = new PdfDictionary();
while (true) {
if (!nextValidToken())
throw new IOException(MessageLocalization.getComposedMessage("unexpected.end.of.file"));
if (tokeniser.getTokenType() == TokenType.END_DIC)
break;
if (tokeniser.getTokenType() != TokenType.NAME)
throw new IOException(MessageLocalization.getComposedMessage("dictionary.key.is.not.a.name"));
PdfName name = new PdfName(tokeniser.getStringValue(), false);
PdfObject obj = readPRObject();
int type = obj.type();
if (-type == TokenType.END_DIC.ordinal())
throw new IOException(MessageLocalization.getComposedMessage("unexpected.gt.gt"));
if (-type == TokenType.END_ARRAY.ordinal())
throw new IOException(MessageLocalization.getComposedMessage("unexpected.close.bracket"));
dic.put(name, obj);
}
return dic;
}
/**
* Reads an array. The tokeniser must be positioned past the "[" token.
* @return an array
* @throws IOException on error
*/
public PdfArray readArray() throws IOException {
PdfArray array = new PdfArray();
while (true) {
PdfObject obj = readPRObject();
int type = obj.type();
if (-type == TokenType.END_ARRAY.ordinal())
break;
if (-type == TokenType.END_DIC.ordinal())
throw new IOException(MessageLocalization.getComposedMessage("unexpected.gt.gt"));
array.add(obj);
}
return array;
}
/**
* Reads a pdf object.
* @return the pdf object
* @throws IOException on error
*/
public PdfObject readPRObject() throws IOException {
if (!nextValidToken())
return null;
TokenType type = tokeniser.getTokenType();
switch (type) {
case START_DIC: {
PdfDictionary dic = readDictionary();
return dic;
}
case START_ARRAY:
return readArray();
case STRING:
PdfString str = new PdfString(tokeniser.getStringValue(), null).setHexWriting(tokeniser.isHexString());
return str;
case NAME:
return new PdfName(tokeniser.getStringValue(), false);
case NUMBER:
return new PdfNumber(tokeniser.getStringValue());
case OTHER:
return new PdfLiteral(COMMAND_TYPE, tokeniser.getStringValue());
default:
return new PdfLiteral(-type.ordinal(), tokeniser.getStringValue());
}
}
/**
* Reads the next token skipping over the comments.
* @return <CODE>true</CODE> if a token was read, <CODE>false</CODE> if the end of content was reached
* @throws IOException on error
*/
public boolean nextValidToken() throws IOException {
while (tokeniser.nextToken()) {
if (tokeniser.getTokenType() == TokenType.COMMENT)
continue;
return true;
}
return false;
}
}
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