/*
* Copyright 2006 Ralf Joachim
*
* 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
*
* 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.exolab.javasource;
/**
* A class to format comments.
*
* @author <a href="mailto:ralf DOT joachim AT syscon DOT eu">Ralf Joachim</a>
* @version $Revision: 6668 $ $Date: 2005-05-08 12:32:06 -0600 (Sun, 08 May 2005) $
* @since 1.1
*/
public final class JCommentFormatter {
//--------------------------------------------------------------------------
private String _comment = null;
private int _maxLength = JComment.MAX_LENGTH;
private int _offset = 0;
private int _length = 0;
private String _prefix = null;
private StringBuffer _sb = null;
//--------------------------------------------------------------------------
/**
* Creates a new LineFormatter for the given comment.
*
* @param comment The String to format.
* @param maxLength The maximum number of characters per line.
* @param prefix A prefix to append to the beginning of each line.
*/
public JCommentFormatter(final String comment, final int maxLength, final String prefix) {
_comment = comment;
if (comment != null) { _length = comment.length(); }
_sb = new StringBuffer();
_maxLength = maxLength;
_prefix = prefix;
}
//--------------------------------------------------------------------------
public boolean hasMoreLines() {
if (_comment == null) { return false; }
return (_offset < _length);
}
public String nextLine() {
if (_comment == null) { return null; }
if (_offset >= _length) { return null; }
_sb.setLength(0);
if (_prefix != null) { _sb.append(_prefix); }
int max = _offset + _maxLength;
if (max > this._length) { max = this._length; }
int index = _offset;
int breakable = _offset;
for ( ; index < max; index++) {
char ch = _comment.charAt(index);
if (isNewLine(ch)) {
_sb.append(_comment.substring(_offset, index));
_offset = index + 1;
return _sb.toString();
}
if (isWhitespace(ch)) { breakable = index; }
}
if (index < _length - 1) {
//-- if we could not find a breakable character, we must look
//-- ahead
if (_offset == breakable) {
while (index < _length) {
if (isBreakable(_comment.charAt(index))) { break; }
++index;
}
} else {
index = breakable;
}
}
_sb.append(_comment.substring(_offset, index));
_offset = index + 1;
return _sb.toString();
}
/**
* Returns true if we can break a line at this character.
*
* @param ch Character to examine.
* @return True if we can break a line at this character.
*/
private boolean isBreakable(final char ch) {
return (isWhitespace(ch) || isNewLine(ch));
}
/**
* Returns true if this character is whitespace.
*
* @param ch Character to examine.
* @return True if this character is whitespace.
*/
private boolean isWhitespace(final char ch) {
return ((ch == ' ') || (ch == '\t'));
}
/**
* Returns true if this character is a new line character.
*
* @param ch Character to examine.
* @return True if this character is a new line character.
*/
private boolean isNewLine(final char ch) {
return ((ch == '\n') || (ch == '\r'));
}
//--------------------------------------------------------------------------
}