/*
* WhitespaceRule.java
* :tabSize=4:indentSize=4:noTabs=false:
* :folding=explicit:collapseFolds=1:
*
* Copyright (C) 2007 Marcelo Vanzin
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or any later version.
*
* 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
package org.gjt.sp.jedit.indent;
import java.util.List;
import org.gjt.sp.jedit.buffer.JEditBuffer;
/**
* Whitespace rule. This rule cancels all indent actions in the
* following case:
*
* <ul>
* <li>The previous line is all whitespace</li>
* <li>The current line is not empty</li>
* </ul>
*
* <p>The result is that this rule won't allow the indentation to be
* increased, only decreased (by rules triggered by unindentThisLine).
* If the requirements above do not apply, this rule does nothing.</p>
*
* @author Marcelo Vanzin
* @version $Id$
* @since jEdit 4.3pre10
*/
public class WhitespaceRule implements IndentRule
{
public void apply(JEditBuffer buffer, int thisLineIndex,
int prevLineIndex, int prevPrevLineIndex,
List<IndentAction> indentActions)
{
/* Don't apply this rule if the current line is empty. */
CharSequence current = buffer.getLineSegment(thisLineIndex);
boolean found = false;
for (int i = 0; i < current.length(); i++)
{
if (!Character.isWhitespace(current.charAt(i)))
{
found = true;
break;
}
}
if (!found)
return;
/* Check if the previous line is empty. */
if (prevLineIndex >= 0) {
CharSequence previous = buffer.getLineSegment(prevLineIndex);
for (int i = 0; i < previous.length(); i++)
{
if (!Character.isWhitespace(previous.charAt(i)))
return;
}
}
indentActions.add(new IndentAction.NoIncrease());
}
}