/jEdit/tags/jedit-4-5-pre1/org/gjt/sp/jedit/buffer/IndentFoldHandler.java
Java | 136 lines | 68 code | 9 blank | 59 comment | 10 complexity | 2535a1190463d89eef356749bacfe855 MD5 | raw file
Possible License(s): BSD-3-Clause, AGPL-1.0, Apache-2.0, LGPL-2.0, LGPL-3.0, GPL-2.0, CC-BY-SA-3.0, LGPL-2.1, GPL-3.0, MPL-2.0-no-copyleft-exception, IPL-1.0
- /*
- * IndentFoldHandler.java - Indent-based fold handler
- * :tabSize=8:indentSize=8:noTabs=false:
- * :folding=explicit:collapseFolds=1:
- *
- * Copyright (C) 2001, 2002 Slava Pestov
- *
- * 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.buffer;
- import java.util.ArrayList;
- import java.util.List;
- import javax.swing.text.Segment;
- /**
- * A fold handler that folds lines based on their indent level.
- * @author Slava Pestov
- * @version $Id: IndentFoldHandler.java 16133 2009-08-31 21:07:15Z shlomy $
- * @since jEdit 4.0pre1
- */
- public class IndentFoldHandler extends FoldHandler
- {
- public IndentFoldHandler()
- {
- super("indent");
- }
- // Returns the width of leading whitespace in the given segment
- // if it contains non-whitespace characters, or (-1) otherwise.
- private int getLeadingWhitespaceWidth(Segment seg, int tabSize)
- {
- int offset = seg.offset;
- int count = seg.count;
- int whitespace = 0;
- for(int i = 0; i < count; i++)
- {
- switch(seg.array[offset + i])
- {
- case ' ':
- whitespace++;
- break;
- case '\t':
- whitespace += (tabSize - whitespace % tabSize);
- break;
- default:
- return whitespace;
- }
- }
- return (-1);
- }
- //{{{ getFoldLevel() method
- /**
- * Returns the fold level of the specified line. For a whitespace-only
- * line, returns the fold level of the next non-whitespace line, or
- * the level of the previous line if no non-whitespace line follows or if
- * the level of the previous line is higher.
- * @param buffer The buffer in question
- * @param lineIndex The line index
- * @param seg A segment the fold handler can use to obtain any
- * text from the buffer, if necessary
- * @return The fold level of the specified line
- * @since jEdit 4.0pre1
- */
- public int getFoldLevel(JEditBuffer buffer, int lineIndex, Segment seg)
- {
- int tabSize = buffer.getTabSize();
- // Look for first non-whitespace line starting at lineIndex
- int prevLevel = 0;
- for (int index = lineIndex; index < buffer.getLineCount(); index++)
- {
- buffer.getLineText(index,seg);
- int whitespace = getLeadingWhitespaceWidth(seg,tabSize);
- if(whitespace >= 0) // Non-whitespace found on line
- return (whitespace > prevLevel) ? whitespace : prevLevel;
- if(index == 0)
- return 0;
- if(index == lineIndex)
- prevLevel = buffer.getFoldLevel(lineIndex - 1);
- }
- // All lines from lineIndex are whitespace-only - use fold
- // level of previous line.
- return prevLevel;
- } //}}}
- //{{{ getPrecedingFoldLevels() method
- /**
- * Returns the fold levels of the lines preceding the specified line,
- * which depend on the specified line.
- * @param buffer The buffer in question
- * @param lineIndex The line index
- * @param seg A segment the fold handler can use to obtain any
- * @param lineFoldLevel The fold level of the specified line
- * @return The fold levels of the preceding lines, in decreasing line
- * number order (i.e. bottomost line first).
- * @since jEdit 4.3pre18
- */
- public List<Integer> getPrecedingFoldLevels(JEditBuffer buffer,
- int lineIndex, Segment seg, int lineFoldLevel)
- {
- List<Integer> precedingFoldLevels = new ArrayList<Integer>();
- int tabSize = buffer.getTabSize();
- int whitespace = 0;
- int index;
- // Find previous non-whitespace-only line
- for (index = lineIndex - 1; index > 0; index--)
- {
- buffer.getLineText(index,seg);
- whitespace = getLeadingWhitespaceWidth(seg,tabSize);
- if (whitespace >= 0)
- break;
- }
- int max = (lineFoldLevel > whitespace) ? lineFoldLevel : whitespace;
- for (index++; index < lineIndex; index++)
- precedingFoldLevels.add(Integer.valueOf(max));
- return precedingFoldLevels;
- }
- //}}}
- }