/*
* 07/28/2008
*
* RtfToText.java - Returns the plain text version of RTF documents.
* Copyright (C) 2008 Robert Futrell
* robert_futrell at users.sourceforge.net
* http://fifesoft.com/rsyntaxtextarea
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/
package org.fife.ui.rsyntaxtextarea;
import java.io.*;
/**
* Gets the plain text version of RTF documents.
* <p>
*
* This is used by <code>RtfTransferable</code> to return the plain text version of the transferable when the receiver
* does not support RTF.
*
* @author Robert Futrell
* @version 1.0
*/
class RtfToText {
private Reader r;
private StringBuffer sb;
private StringBuffer controlWord;
private int blockCount;
private boolean inControlWord;
/**
* Private constructor.
*
* @param r
* The reader to read RTF text from.
*/
private RtfToText(Reader r) {
this.r = r;
sb = new StringBuffer();
controlWord = new StringBuffer();
blockCount = 0;
inControlWord = false;
}
/**
* Converts the RTF text read from this converter's <code>Reader</code> into plain text. It is the caller's
* responsibility to close the reader after this method is called.
*
* @return The plain text.
* @throws IOException
* If an IO error occurs.
*/
private String convert() throws IOException {
// Skip over first curly brace as the whole file is in '{' and '}'
int i = r.read();
if (i != '{') {
throw new IOException("Invalid RTF file");
}
while ((i = r.read()) != -1) {
char ch = (char) i;
switch (ch) {
case '{':
if (inControlWord && controlWord.length() == 0) { // "\{"
sb.append('{');
controlWord.setLength(0);
inControlWord = false;
}
else {
blockCount++;
}
break;
case '}':
if (inControlWord && controlWord.length() == 0) { // "\}"
sb.append('}');
controlWord.setLength(0);
inControlWord = false;
}
else {
blockCount--;
}
break;
case '\\':
if (blockCount == 0) {
if (inControlWord) {
if (controlWord.length() == 0) { // "\\"
sb.append('\\');
controlWord.setLength(0);
inControlWord = false;
}
else {
endControlWord();
}
}
inControlWord = true;
}
break;
case ' ':
if (blockCount == 0) {
if (inControlWord) {
endControlWord();
}
else {
sb.append(' ');
}
}
break;
case '\r':
case '\n':
if (blockCount == 0) {
if (inControlWord) {
endControlWord();
}
// Otherwise, ignore
}
break;
default:
if (blockCount == 0) {
if (inControlWord) {
controlWord.append(ch);
}
else {
sb.append(ch);
}
}
break;
}
}
return sb.toString();
}
/**
* Ends a control word. Checks whether it is a common one that affects the plain text output (such as "
* <code>par</code>" or "<code>tab</code>") and updates the text buffer accordingly.
*/
private void endControlWord() {
String word = controlWord.toString();
if ("par".equals(word)) {
sb.append('\n');
}
else if ("tab".equals(word)) {
sb.append('\t');
}
controlWord.setLength(0);
inControlWord = false;
}
/**
* Converts the contents of the specified byte array representing an RTF document into plain text.
*
* @param rtf
* The byte array representing an RTF document.
* @return The contents of the RTF document, in plain text.
* @throws IOException
* If an IO error occurs.
*/
public static String getPlainText(byte[] rtf) throws IOException {
return getPlainText(new ByteArrayInputStream(rtf));
}
/**
* Converts the contents of the specified RTF file to plain text.
*
* @param file
* The RTF file to convert.
* @return The contents of the file, in plain text.
* @throws IOException
* If an IO error occurs.
*/
public static String getPlainText(File file) throws IOException {
return getPlainText(new BufferedReader(new FileReader(file)));
}
/**
* Converts the contents of the specified input stream to plain text. The input stream will be closed when this
* method returns.
*
* @param in
* The input stream to convert.
* @return The contents of the stream, in plain text.
* @throws IOException
* If an IO error occurs.
*/
public static String getPlainText(InputStream in) throws IOException {
return getPlainText(new InputStreamReader(in, "US-ASCII"));
}
/**
* Converts the contents of the specified <code>Reader</code> to plain text.
*
* @param r
* The <code>Reader</code>.
* @return The contents of the <code>Reader</code>, in plain text.
* @throws IOException
* If an IO error occurs.
*/
private static String getPlainText(Reader r) throws IOException {
try {
RtfToText converter = new RtfToText(r);
return converter.convert();
} finally {
r.close();
}
}
/**
* Converts the contents of the specified String to plain text.
*
* @param rtf
* A string whose contents represent an RTF document.
* @return The contents of the String, in plain text.
* @throws IOException
* If an IO error occurs.
*/
public static String getPlainText(String rtf) throws IOException {
return getPlainText(new StringReader(rtf));
}
}