/*
* Sun Public License Notice
*
* The contents of this file are subject to the Sun Public License
* Version 1.0 (the "License"). You may not use this file except in
* compliance with the License. A copy of the License is available at
* http://www.sun.com/
*
* The Original Code is NetBeans. The Initial Developer of the Original
* Code is Sun Microsystems, Inc. Portions Copyright 1997-2003 Sun
* Microsystems, Inc. All Rights Reserved.
*/
package org.netbeans.editor;
import javax.swing.text.Segment;
import java.io.IOException;
import java.io.Reader;
/**
* Converters handling the various line separators.
*
* @author Miloslav Metelka
* @version 1.00
*/
public class LineSeparatorConversion {
/**
* Default size of the conversion buffers.
*/
private static final int DEFAULT_CONVERSION_BUFFER_SIZE = 16384;
private LineSeparatorConversion() {
// no instances
}
/**
* Convert all the occurrences of '\r' and '\r\n' in the text to '\n'.
* @param text text being converted
* @return converted text with '\n' instead of '\r' and '\r\n'.
*/
public static String convertToLineFeed(String text) {
StringBuffer output = new StringBuffer();
convertToLineFeed(text, 0, text.length(), output);
return output.toString();
}
/**
* Convert all the occurrences of '\r' and '\r\n' in the text to '\n'.
* @param text text being converted
* @param offset offset of the first character in the text to be converted.
* @param length number of characters to be converted.
* @param output output buffer to which the converted characters are added.
*/
public static void convertToLineFeed(String text, int offset, int length,
StringBuffer output) {
int endOffset = offset + length;
boolean lastCharCR = false; // whether last char was '\r'
while (offset < endOffset) {
char ch = text.charAt(offset++);
if (lastCharCR && ch == '\n') { // found CRLF sequence
lastCharCR = false;
} else { // not CRLF sequence
if (ch == '\r') {
output.append('\n');
lastCharCR = true;
} else { // current char not '\r'
lastCharCR = false;
output.append(ch);
}
}
}
}
/**
* Convert all the occurrences of '\n' in the given text
* to the requested line separator.
* @param text text being converted
* @param lineFeedReplace characters that replace the '\n' character
* in the converted text.
* @return converted text with replaced '\n' by characters from lineFeedReplace string
*/
public static String convertFromLineFeed(String text, String lineFeedReplace) {
StringBuffer output = new StringBuffer();
convertFromLineFeed(text, 0, text.length(), lineFeedReplace, output);
return output.toString();
}
/**
* Convert all the occurrences of '\n' in the given text
* to the requested line separator.
* @param text text being converted
* @param offset offset of the first character in the text to be converted.
* @param length number of characters to be converted.
* @param lineFeedReplace characters that replace the '\n' character in the output
* @param output output buffer to which the converted characters are added.
*/
public static void convertFromLineFeed(String text, int offset, int length,
String lineFeedReplace, StringBuffer output) {
int lineFeedReplaceLength = lineFeedReplace.length();
int endOffset = offset + length;
while (offset < endOffset) {
char ch = text.charAt(offset++);
if (ch == '\n') {
for (int i = 0; i < lineFeedReplaceLength; i++) {
output.append(lineFeedReplace.charAt(i));
}
} else {
output.append(ch);
}
}
}
/**
* Convert all the occurrences of '\r' and '\r\n' in the text to '\n'.
* This class does conversion in chunks of fixed size
* and is therefore suitable for conversion of readers
* where the size is unknown.
*/
public static class ToLineFeed {
private Reader reader;
private Segment convertedText;
private boolean lastCharCR;
public ToLineFeed(Reader reader) {
this(reader, DEFAULT_CONVERSION_BUFFER_SIZE);
}
public ToLineFeed(Reader reader, int convertBufferSize) {
this.reader = reader;
convertedText = new Segment();
convertedText.array = new char[convertBufferSize];
}
public Segment nextConverted() throws IOException {
if (reader == null) { // no more chars to read
return null;
}
int readOffset = 0;
int readSize = readBuffer(reader, convertedText.array, readOffset, true);
if (readSize == 0) { // no more chars in reader
reader.close();
reader = null;
return null;
}
if (lastCharCR && readSize > 0 && convertedText.array[readOffset] == '\n') {
/* the preceding '\r' was already converted to '\n'
* in the previous buffer so here just skip initial '\n'
*/
readOffset++;
readSize--;
}
convertedText.offset = readOffset;
convertedText.count = readSize;
lastCharCR = convertSegmentToLineFeed(convertedText);
return convertedText;
}
/**
* Convert all the '\r\n' or '\r' to '\n' (linefeed).
* This method
* @param text the text to be converted. Text is converted
* in the original array of the given segment.
* The <CODE>count</CODE> field
* of the text parameter will possibly be changed by the conversion
* if '\r\n' sequences are present.
* @return whether the last character in the text was the '\r' character.
* That character was already converted to '\n' and is present
* in the segment. However this notification is important
* because if there would be '\n' at the begining
* of the next buffer then that character should be skipped.
*/
private static boolean convertSegmentToLineFeed(Segment text) {
char[] chars = text.array;
int storeOffset = text.offset; // offset at which chars are stored
int endOffset = storeOffset + text.count;
boolean storeChar = false; // to prevent copying same chars to same offsets
boolean lastCharCR = false; // whether last char was '\r'
for (int offset = storeOffset; offset < endOffset; offset++) {
char ch = chars[offset];
if (lastCharCR && ch == '\n') { // found CRLF sequence
lastCharCR = false;
storeChar = true; // storeOffset now differs from offset
} else { // not CRLF sequence
if (ch == '\r') {
lastCharCR = true;
chars[storeOffset++] = '\n'; // convert it to '\n'
} else { // current char not '\r'
lastCharCR = false;
if (storeChar) {
chars[storeOffset] = ch;
}
storeOffset++;
}
}
}
text.count = storeOffset - text.offset;
return lastCharCR;
}
private static int readBuffer(Reader reader, char[] buffer, int offset,
boolean joinReads) throws IOException {
int maxReadSize = buffer.length - offset;
int totalReadSize = 0;
do {
int readSize = 0;
while (readSize == 0) { // eliminate empty reads
readSize = reader.read(buffer, offset, maxReadSize);
}
if (readSize == -1) {
break; // no more chars in reader
}
totalReadSize += readSize;
offset += readSize;
maxReadSize -= readSize;
} while (joinReads && maxReadSize > 0);
return totalReadSize;
}
}
/**
* Convert all the occurrences of '\n' in the given text
* to the requested line separator.
* This class does conversion in chunks of fixed size
* and is therefore suitable for conversion of large
* texts.
*/
public static class FromLineFeed {
private Object charArrayOrSequence;
private int offset;
private int endOffset;
private String lineFeedReplace;
private Segment convertedText;
public FromLineFeed(char[] source, int offset, int length,
String lineFeedReplace) {
this(source, offset, length, lineFeedReplace, DEFAULT_CONVERSION_BUFFER_SIZE);
}
public FromLineFeed(char[] source, int offset, int length,
String lineFeedReplace, int conversionSegmentSize) {
this((Object)source, offset, length, lineFeedReplace, conversionSegmentSize);
}
public FromLineFeed(String text, int offset, int length,
String lineFeedReplace) {
this(text, offset, length, lineFeedReplace, DEFAULT_CONVERSION_BUFFER_SIZE);
}
public FromLineFeed(String text, int offset, int length,
String lineFeedReplace, int conversionSegmentSize) {
this((Object)text, offset, length, lineFeedReplace, conversionSegmentSize);
}
private FromLineFeed(Object charArrayOrSequence, int offset, int length,
String lineFeedReplace, int conversionSegmentSize) {
if (conversionSegmentSize < lineFeedReplace.length()) {
throw new IllegalArgumentException("conversionSegmentSize="
+ conversionSegmentSize + " < lineFeedReplace.length()="
+ lineFeedReplace.length()
);
}
this.charArrayOrSequence = charArrayOrSequence;
this.offset = offset;
this.endOffset = offset + length;
this.lineFeedReplace = lineFeedReplace;
convertedText = new Segment();
convertedText.array = new char[conversionSegmentSize];
}
public Segment nextConverted() {
if (offset == endOffset) { // no more chars to convert
return null;
}
// [PENDING-PERF] optimization for '\n' -> arraycopy
char[] convertedArray = convertedText.array;
int convertedArrayLength = convertedArray.length;
int convertedOffset = 0;
/* Determine whether the source is char-sequence
* or char buffer.
* Assign either sourceText or sourceArray but not both.
*/
String sourceText;
char[] sourceArray;
if (charArrayOrSequence instanceof String) {
sourceText = (String)charArrayOrSequence;
sourceArray = null;
} else {
sourceArray = (char[])charArrayOrSequence;
sourceText = null;
}
int lineFeedReplaceLength = lineFeedReplace.length();
while (offset < endOffset
&& convertedArrayLength - convertedOffset >= lineFeedReplaceLength
) {
char ch = (sourceText != null)
? sourceText.charAt(offset++)
: sourceArray[offset++];
if (ch == '\n') {
for (int i = 0; i < lineFeedReplaceLength; i++) {
convertedArray[convertedOffset++] = lineFeedReplace.charAt(i);
}
} else {
convertedArray[convertedOffset++] = ch;
}
}
convertedText.offset = 0;
convertedText.count = convertedOffset;
return convertedText;
}
}
public static class InitialSeparatorReader extends Reader {
private static final int AFTER_CR_STATUS = -1;
private static final int INITIAL_STATUS = 0;
private static final int CR_SEPARATOR = 1;
private static final int LF_SEPARATOR = 2;
private static final int CRLF_SEPARATOR = 3;
private Reader delegate;
private int status = INITIAL_STATUS;
public InitialSeparatorReader(Reader delegate) {
this.delegate = delegate;
}
public String getInitialSeparator() {
String separator;
switch (status) {
case CR_SEPARATOR:
separator = "\r";
break;
case LF_SEPARATOR:
separator = "\n";
break;
case CRLF_SEPARATOR:
separator = "\r\n";
break;
case AFTER_CR_STATUS: // '\r' was last char
separator = "\r";
break;
default:
separator = "\n"; // default
break;
}
return separator;
}
private void resolveSeparator(char ch) {
switch (status) {
case INITIAL_STATUS:
switch (ch) {
case '\r':
status = AFTER_CR_STATUS;
break;
case '\n':
status = LF_SEPARATOR;
break;
}
break;
case AFTER_CR_STATUS:
switch (ch) {
case '\n':
status = CRLF_SEPARATOR;
break;
default:
status = CR_SEPARATOR;
break;
}
break;
default:
switch (ch) {
case '\r':
status = AFTER_CR_STATUS;
break;
case '\n':
status = LF_SEPARATOR;
break;
}
break;
}
}
private boolean isSeparatorResolved() {
return (status > 0);
}
public void close() throws IOException {
if (delegate == null) {
return;
}
delegate.close();
delegate = null;
}
public int read(char[] cbuf, int off, int len) throws IOException {
if (delegate == null) {
throw new IOException("Reader already closed.");
}
int readLen = delegate.read(cbuf, off, len);
for (int endOff = off + readLen;
off < endOff && !isSeparatorResolved();
off++
) {
resolveSeparator(cbuf[off]);
}
return readLen;
}
public int read() throws IOException {
if (delegate == null) {
throw new IOException("Reader already closed.");
}
int r = delegate.read();
if (r != -1 && !isSeparatorResolved()) {
resolveSeparator((char)r);
}
return r;
}
}
}