diff options
Diffstat (limited to 'libjava/classpath/javax/swing/text/GapContent.java')
| -rw-r--r-- | libjava/classpath/javax/swing/text/GapContent.java | 1095 |
1 files changed, 0 insertions, 1095 deletions
diff --git a/libjava/classpath/javax/swing/text/GapContent.java b/libjava/classpath/javax/swing/text/GapContent.java deleted file mode 100644 index 2e68fb5..0000000 --- a/libjava/classpath/javax/swing/text/GapContent.java +++ /dev/null @@ -1,1095 +0,0 @@ -/* GapContent.java -- - Copyright (C) 2002, 2004, 2005, 2006 Free Software Foundation, Inc. - -This file is part of GNU Classpath. - -GNU Classpath 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, or (at your option) -any later version. - -GNU Classpath 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 GNU Classpath; see the file COPYING. If not, write to the -Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA -02110-1301 USA. - -Linking this library statically or dynamically with other modules is -making a combined work based on this library. Thus, the terms and -conditions of the GNU General Public License cover the whole -combination. - -As a special exception, the copyright holders of this library give you -permission to link this library with independent modules to produce an -executable, regardless of the license terms of these independent -modules, and to copy and distribute the resulting executable under -terms of your choice, provided that you also meet, for each linked -independent module, the terms and conditions of the license of that -module. An independent module is a module which is not derived from -or based on this library. If you modify this library, you may extend -this exception to your version of the library, but you are not -obligated to do so. If you do not wish to do so, delete this -exception statement from your version. */ - - -package javax.swing.text; - -import java.io.Serializable; -import java.lang.ref.ReferenceQueue; -import java.lang.ref.WeakReference; -import java.util.ArrayList; -import java.util.Collections; -import java.util.Iterator; -import java.util.List; -import java.util.Vector; - -import javax.swing.undo.AbstractUndoableEdit; -import javax.swing.undo.CannotRedoException; -import javax.swing.undo.CannotUndoException; -import javax.swing.undo.UndoableEdit; - -/** - * This implementation of {@link AbstractDocument.Content} uses a gapped buffer. - * This takes advantage of the fact that text area content is mostly inserted - * sequentially. The buffer is a char array that maintains a gap at the current - * insertion point. If characters a inserted at gap boundaries, the cost is - * minimal (simple array access). The array only has to be shifted around when - * the insertion point moves (then the gap also moves and one array copy is - * necessary) or when the gap is filled up and the buffer has to be enlarged. - */ -public class GapContent - implements AbstractDocument.Content, Serializable -{ - - /** - * A {@link Position} implementation for <code>GapContent</code>. - */ - class GapContentPosition - implements Position - { - - /** - * The index to the positionMarks array entry, which in turn holds the - * mark into the buffer array. - */ - Mark mark; - - /** - * Returns the current offset of this Position within the content. - * - * @return the current offset of this Position within the content. - */ - public int getOffset() - { - return mark.getOffset(); - } - } - - /** - * Holds a mark into the buffer that is used by GapContentPosition to find - * the actual offset of the position. This is pulled out of the - * GapContentPosition object so that the mark and position can be handled - * independently, and most important, so that the GapContentPosition can - * be garbage collected while we still hold a reference to the Mark object. - */ - private class Mark - extends WeakReference - { - /** - * The actual mark into the buffer. - */ - int mark; - - /** - * Creates a new Mark object for the specified offset. - * - * @param offset the offset - */ - Mark(int offset) - { - super(null); - mark = offset; - } - - Mark(int offset, GapContentPosition pos, ReferenceQueue queue) - { - super(pos, queue); - mark = offset; - } - - /** - * Returns the offset of the mark. - * - * @return the offset of the mark - */ - int getOffset() - { - int res = mark; - if (mark >= gapStart) - res -= (gapEnd - gapStart); - return Math.max(0, res); - } - - /** - * Returns the GapContentPosition that is associated ith this mark. - * This fetches the weakly referenced position object. - * - * @return the GapContentPosition that is associated ith this mark - */ - GapContentPosition getPosition() - { - return (GapContentPosition) get(); - } - - } - - /** - * Stores a reference to a mark that can be resetted to the original value - * after a mark has been moved. This is used for undoing actions. - */ - private class UndoPosRef - { - /** - * The mark that might need to be reset. - */ - private Mark mark; - - /** - * The original offset to reset the mark to. - */ - private int undoOffset; - - /** - * Creates a new UndoPosRef. - * - * @param m the mark - */ - UndoPosRef(Mark m) - { - mark = m; - undoOffset = mark.getOffset(); - } - - /** - * Resets the position of the mark to the value that it had when - * creating this UndoPosRef. - */ - void reset() - { - if (undoOffset <= gapStart) - mark.mark = undoOffset; - else - mark.mark = (gapEnd - gapStart) + undoOffset; - } - } - - private class InsertUndo extends AbstractUndoableEdit - { - public int where, length; - String text; - private Vector positions; - - public InsertUndo(int start, int len) - { - where = start; - length = len; - } - - public void undo () throws CannotUndoException - { - super.undo(); - try - { - positions = getPositionsInRange(null, where, length); - text = getString(where, length); - remove(where, length); - } - catch (BadLocationException ble) - { - throw new CannotUndoException(); - } - } - - public void redo () throws CannotUndoException - { - super.redo(); - try - { - insertString(where, text); - if (positions != null) - { - updateUndoPositions(positions, where, length); - positions = null; - } - } - catch (BadLocationException ble) - { - throw new CannotRedoException(); - } - } - - } - - private class UndoRemove extends AbstractUndoableEdit - { - public int where; - String text; - - /** - * The positions in the removed range. - */ - private Vector positions; - - public UndoRemove(int start, String removedText) - { - where = start; - text = removedText; - positions = getPositionsInRange(null, start, removedText.length()); - } - - public void undo () throws CannotUndoException - { - super.undo(); - try - { - insertString(where, text); - if (positions != null) - updateUndoPositions(positions, where, text.length()); - } - catch (BadLocationException ble) - { - throw new CannotUndoException(); - } - } - - public void redo () throws CannotUndoException - { - super.redo(); - try - { - text = getString(where, text.length()); - positions = getPositionsInRange(null, where, text.length()); - remove(where, text.length()); - } - catch (BadLocationException ble) - { - throw new CannotRedoException(); - } - } - - } - - /** The serialization UID (compatible with JDK1.5). */ - private static final long serialVersionUID = -6226052713477823730L; - - /** - * This is the default buffer size and the amount of bytes that a buffer is - * extended if it is full. - */ - static final int DEFAULT_BUFSIZE = 10; - - /** - * The text buffer. - */ - char[] buffer; - - /** - * The index of the first character of the gap. - */ - int gapStart; - - /** - * The index of the character after the last character of the gap. - */ - int gapEnd; - - // FIXME: We might want to track GC'ed GapContentPositions and remove their - // corresponding marks, or alternativly, perform some regular cleanup of - // the positionMarks array. - - /** - * Holds the marks for positions. These marks are referenced by the - * GapContentPosition instances by an index into this array. - * - * This is package private to avoid accessor synthetic methods. - */ - ArrayList marks; - - /** - * The number of unused marks. - */ - private int garbageMarks; - - /** - * A 'static' mark that is used for searching. - */ - private Mark searchMark = new Mark(0); - - /** - * Queues all references to GapContentPositions that are about to be - * GC'ed. This is used to remove the corresponding marks from the - * positionMarks array if the number of references to that mark reaches zero. - * - * This is package private to avoid accessor synthetic methods. - */ - ReferenceQueue queueOfDeath; - - /** - * Creates a new GapContent object. - */ - public GapContent() - { - this(DEFAULT_BUFSIZE); - } - - /** - * Creates a new GapContent object with a specified initial size. - * - * @param size the initial size of the buffer - */ - public GapContent(int size) - { - size = Math.max(size, 2); - buffer = (char[]) allocateArray(size); - gapStart = 1; - gapEnd = size; - buffer[0] = '\n'; - marks = new ArrayList(); - queueOfDeath = new ReferenceQueue(); - } - - /** - * Allocates an array of the specified length that can then be used as - * buffer. - * - * @param size the size of the array to be allocated - * - * @return the allocated array - */ - protected Object allocateArray(int size) - { - return new char[size]; - } - - /** - * Returns the length of the allocated buffer array. - * - * @return the length of the allocated buffer array - */ - protected int getArrayLength() - { - return buffer.length; - } - - /** - * Returns the length of the content. - * - * @return the length of the content - */ - public int length() - { - return buffer.length - (gapEnd - gapStart); - } - - /** - * Inserts a string at the specified position. - * - * @param where the position where the string is inserted - * @param str the string that is to be inserted - * - * @return an UndoableEdit object - * - * @throws BadLocationException if <code>where</code> is not a valid - * location in the buffer - */ - public UndoableEdit insertString(int where, String str) - throws BadLocationException - { - // check arguments - int length = length(); - int strLen = str.length(); - - if (where < 0) - throw new BadLocationException("The where argument cannot be smaller" - + " than the zero", where); - - if (where > length) - throw new BadLocationException("The where argument cannot be greater" - + " than the content length", where); - - InsertUndo undo = new InsertUndo(where, strLen); - replace(where, 0, str.toCharArray(), strLen); - - return undo; - } - - /** - * Removes a piece of content at th specified position. - * - * @param where the position where the content is to be removed - * @param nitems number of characters to be removed - * - * @return an UndoableEdit object - * - * @throws BadLocationException if <code>where</code> is not a valid - * location in the buffer - */ - public UndoableEdit remove(int where, int nitems) throws BadLocationException - { - // check arguments - int length = length(); - - if ((where + nitems) >= length) - throw new BadLocationException("where + nitems cannot be greater" - + " than the content length", where + nitems); - - String removedText = getString(where, nitems); - UndoRemove undoRemove = new UndoRemove(where, removedText); - replace(where, nitems, null, 0); - - return undoRemove; - } - - /** - * Returns a piece of content as String. - * - * @param where the start location of the fragment - * @param len the length of the fragment - * - * @throws BadLocationException if <code>where</code> or - * <code>where + len</code> are no valid locations in the buffer - */ - public String getString(int where, int len) throws BadLocationException - { - Segment seg = new Segment(); - try - { - getChars(where, len, seg); - return new String(seg.array, seg.offset, seg.count); - } - catch (StringIndexOutOfBoundsException ex) - { - int invalid = 0; - if (seg.offset < 0 || seg.offset >= seg.array.length) - invalid = seg.offset; - else - invalid = seg.offset + seg.count; - throw new BadLocationException("Illegal location: array.length = " - + seg.array.length + ", offset = " - + seg.offset + ", count = " - + seg.count, invalid); - } - } - - /** - * Fetches a piece of content and stores it in a {@link Segment} object. - * - * If the requested piece of text spans the gap, the content is copied into a - * new array. If it doesn't then it is contiguous and the actual content - * store is returned. - * - * @param where the start location of the fragment - * @param len the length of the fragment - * @param txt the Segment object to store the fragment in - * - * @throws BadLocationException if <code>where</code> or - * <code>where + len</code> are no valid locations in the buffer - */ - public void getChars(int where, int len, Segment txt) - throws BadLocationException - { - // check arguments - int length = length(); - if (where < 0) - throw new BadLocationException("the where argument may not be below zero", where); - if (where >= length) - throw new BadLocationException("the where argument cannot be greater" - + " than the content length", where); - if ((where + len) > length) - throw new BadLocationException("len plus where cannot be greater" - + " than the content length", len + where); - if (len < 0) - throw new BadLocationException("negative length not allowed: ", len); - - // Optimized to copy only when really needed. - if (where + len <= gapStart) - { - // Simple case: completely before gap. - txt.array = buffer; - txt.offset = where; - txt.count = len; - } - else if (where > gapStart) - { - // Completely after gap, adjust offset. - txt.array = buffer; - txt.offset = gapEnd + where - gapStart; - txt.count = len; - } - else - { - // Spans the gap. - int beforeGap = gapStart - where; - if (txt.isPartialReturn()) - { - // Return the part before the gap when partial return is allowed. - txt.array = buffer; - txt.offset = where; - txt.count = beforeGap; - } - else - { - // Copy pieces together otherwise. - txt.array = new char[len]; - txt.offset = 0; - System.arraycopy(buffer, where, txt.array, 0, beforeGap); - System.arraycopy(buffer, gapEnd, txt.array, beforeGap, - len - beforeGap); - txt.count = len; - } - } - } - - /** - * Creates and returns a mark at the specified position. - * - * @param offset the position at which to create the mark - * - * @return the create Position object for the mark - * - * @throws BadLocationException if the offset is not a valid position in the - * buffer - */ - public Position createPosition(final int offset) throws BadLocationException - { - // Implementation note: We used to perform explicit check on the offset - // here. However, this makes some Mauve and Intel/Harmony tests fail - // and luckily enough the GapContent can very well deal with offsets - // outside the buffer bounds. So I removed that check. - - // First do some garbage collections. - while (queueOfDeath.poll() != null) - garbageMarks++; - if (garbageMarks > Math.max(5, marks.size() / 10)) - garbageCollect(); - - // We try to find a GapContentPosition at the specified offset and return - // that. Otherwise we must create a new one. - Mark m; - GapContentPosition pos; - int index = offset; - if (offset >= gapStart) - index += (gapEnd - gapStart); - searchMark.mark = index; - int insertIndex = search(searchMark); - if (!(insertIndex < marks.size() - && (m = (Mark) marks.get(insertIndex)).mark == index - && (pos = m.getPosition()) != null)) - { - // Create new position if none was found. - pos = new GapContentPosition(); - m = new Mark(index, pos, queueOfDeath); - pos.mark = m; - marks.add(insertIndex, m); - } - // Otherwise use the found position. - - return pos; - } - - /** - * Enlarges the gap. This allocates a new bigger buffer array, copy the - * segment before the gap as it is and the segment after the gap at the end - * of the new buffer array. This does change the gapEnd mark but not the - * gapStart mark. - * - * @param newSize the new size of the gap - */ - protected void shiftEnd(int newSize) - { - assert newSize > (gapEnd - gapStart) : "The new gap size must be greater " - + "than the old gap size"; - - int oldEnd = getGapEnd(); - int oldSize = getArrayLength(); - int upper = oldSize - oldEnd; - int size = (newSize + 1) * 2; - int newEnd = size - upper; - - // Copy the data around. - char[] newBuf = (char[]) allocateArray(size); - System.arraycopy(buffer, 0, newBuf, 0, Math.min(size, oldSize)); - buffer = newBuf; - gapEnd = newEnd; - if (upper != 0) - System.arraycopy(buffer, oldEnd, buffer, newEnd, upper); - - // Adjust marks. - int delta = gapEnd - oldEnd; - int adjIndex = searchFirst(oldEnd); - int count = marks.size(); - for (int i = adjIndex; i < count; i++) - { - Mark m = (Mark) marks.get(i); - m.mark += delta; - } - } - - /** - * Shifts the gap to the specified position. - * - * @param newGapStart the new start position of the gap - */ - protected void shiftGap(int newGapStart) - { - int oldStart = gapStart; - int delta = newGapStart - oldStart; - int oldEnd = gapEnd; - int newGapEnd = oldEnd + delta; - int size = oldEnd - oldStart; - - // Shift gap in array. - gapStart = newGapStart; - gapEnd = newGapEnd; - if (delta > 0) - System.arraycopy(buffer, oldEnd, buffer, oldStart, delta); - else - System.arraycopy(buffer, newGapStart, buffer, newGapEnd, -delta); - - // Adjust marks. - if (delta > 0) - { - int adjIndex = searchFirst(oldStart); - int count = marks.size(); - for (int i = adjIndex; i < count; i++) - { - Mark m = (Mark) marks.get(i); - if (m.mark >= newGapEnd) - break; - m.mark -= size; - } - } - else if (delta < 0) - { - int adjIndex = searchFirst(newGapStart); - int count = marks.size(); - for (int i = adjIndex; i < count; i++) - { - Mark m = (Mark) marks.get(i); - if (m.mark >= oldEnd) - break; - m.mark += size; - } - } - resetMarksAtZero(); - } - - /** - * Shifts the gap start downwards. This does not affect the content of the - * buffer. This only updates the gap start and all the marks that are between - * the old gap start and the new gap start. They all are squeezed to the start - * of the gap, because their location has been removed. - * - * @param newGapStart the new gap start - */ - protected void shiftGapStartDown(int newGapStart) - { - if (newGapStart == gapStart) - return; - - assert newGapStart < gapStart : "The new gap start must be less than the " - + "old gap start."; - - // Adjust positions. - int adjIndex = searchFirst(newGapStart); - int count = marks.size(); - for (int i = adjIndex; i < count; i++) - { - Mark m = (Mark) marks.get(i); - if (m.mark > gapStart) - break; - m.mark = gapEnd; - } - - gapStart = newGapStart; - resetMarksAtZero(); - } - - /** - * Shifts the gap end upwards. This does not affect the content of the - * buffer. This only updates the gap end and all the marks that are between - * the old gap end and the new end start. They all are squeezed to the end - * of the gap, because their location has been removed. - * - * @param newGapEnd the new gap start - */ - protected void shiftGapEndUp(int newGapEnd) - { - if (newGapEnd == gapEnd) - return; - - assert newGapEnd > gapEnd : "The new gap end must be greater than the " - + "old gap end."; - - // Adjust marks. - int adjIndex = searchFirst(gapEnd); - int count = marks.size(); - for (int i = adjIndex; i < count; i++) - { - Mark m = (Mark) marks.get(i); - if (m.mark >= newGapEnd) - break; - m.mark = newGapEnd; - } - - - gapEnd = newGapEnd; - resetMarksAtZero(); - } - - /** - * Returns the allocated buffer array. - * - * @return the allocated buffer array - */ - protected final Object getArray() - { - return buffer; - } - - /** - * Replaces a portion of the storage with the specified items. - * - * @param position the position at which to remove items - * @param rmSize the number of items to remove - * @param addItems the items to add at location - * @param addSize the number of items to add - */ - protected void replace(int position, int rmSize, Object addItems, - int addSize) - { - if (addSize == 0) - { - removeImpl(position, rmSize); - return; - } - else if (rmSize > addSize) - { - removeImpl(position + addSize, rmSize - addSize); - } - else - { - int endSize = addSize - rmSize; - int end = addImpl(position + rmSize, endSize); - System.arraycopy(addItems, rmSize, buffer, end, endSize); - addSize = rmSize; - } - System.arraycopy(addItems, 0, buffer, position, addSize); - } - - /** - * Adjusts the positions and gap in response to a remove operation. - * - * @param pos the position at which to remove - * @param num the number of removed items - */ - private void removeImpl(int pos, int num) - { - if (num > 0) - { - int end = pos + num; - int newGapSize = (gapEnd - gapStart) + num; - if (end <= gapStart) - { - if (gapStart != end) - { - shiftGap(end); - } - shiftGapStartDown(gapStart - num); - } - else if (pos >= gapStart) - { - if (gapStart != pos) - { - shiftGap(pos); - } - shiftGapEndUp(gapStart + newGapSize); - } - else - { - shiftGapStartDown(pos); - shiftGapEndUp(gapStart + newGapSize); - } - } - } - - /** - * Adjusts the positions and gap in response to an add operation. - * - * @param pos the position at which to add - * @param num the number of added items - * - * @return the adjusted position - */ - private int addImpl(int pos, int num) - { - int size = gapEnd - gapStart; - if (num == 0) - { - if (pos > gapStart) - pos += size; - return pos; - } - - shiftGap(pos); - if (num >= size) - { - shiftEnd(getArrayLength() - size + num); - size = gapEnd - gapStart; - } - - gapStart += num; - return pos; - } - - /** - * Returns the start index of the gap within the buffer array. - * - * @return the start index of the gap within the buffer array - */ - protected final int getGapStart() - { - return gapStart; - } - - /** - * Returns the end index of the gap within the buffer array. - * - * @return the end index of the gap within the buffer array - */ - protected final int getGapEnd() - { - return gapEnd; - } - - /** - * Returns all <code>Position</code>s that are in the range specified by - * <code>offset</code> and </code>length</code> within the buffer array. - * - * @param v the vector to use; if <code>null</code>, a new Vector is allocated - * @param offset the start offset of the range to search - * @param length the length of the range to search - * - * @return the positions within the specified range - */ - protected Vector getPositionsInRange(Vector v, int offset, int length) - { - int end = offset + length; - int startIndex; - int endIndex; - if (offset < gapStart) - { - if (offset == 0) - startIndex = 0; - else - startIndex = searchFirst(offset); - if (end >= gapStart) - endIndex = searchFirst(end + (gapEnd - gapStart) + 1); - else - endIndex = searchFirst(end + 1); - } - else - { - startIndex = searchFirst(offset + (gapEnd - gapStart)); - endIndex = searchFirst(end + (gapEnd - gapStart) + 1); - } - if (v == null) - v = new Vector(); - for (int i = startIndex; i < endIndex; i++) - { - v.add(new UndoPosRef((Mark) marks.get(i))); - } - return v; - } - - /** - * Resets all <code>Position</code> that have an offset of <code>0</code>, - * to also have an array index of <code>0</code>. This might be necessary - * after a call to <code>shiftGap(0)</code>, since then the marks at offset - * <code>0</code> get shifted to <code>gapEnd</code>. - */ - protected void resetMarksAtZero() - { - if (gapStart != 0) - return; - - for (int i = 0; i < marks.size(); i++) - { - Mark m = (Mark) marks.get(i); - if (m.mark <= gapEnd) - m.mark = 0; - } - } - - /** - * Resets the positions in the specified range to their original offset - * after a undo operation is performed. For example, after removing some - * content, the positions in the removed range will all be set to one - * offset. This method restores the positions to their original offsets - * after an undo. - * - * @param positions the positions to update - * @param offset - * @param length - */ - protected void updateUndoPositions(Vector positions, int offset, int length) - { - for (Iterator i = positions.iterator(); i.hasNext();) - { - UndoPosRef undoPosRef = (UndoPosRef) i.next(); - undoPosRef.reset(); - } - - // Resort marks. - Collections.sort(marks); - } - - /** - * Outputs debugging info to System.err. It prints out the buffer array, - * the gapStart is marked by a < sign, the gapEnd is marked by a > - * sign and each position is marked by a # sign. - */ - private void dump() - { - System.err.println("GapContent debug information"); - System.err.println("buffer length: " + buffer.length); - System.err.println("gap start: " + gapStart); - System.err.println("gap end: " + gapEnd); - for (int i = 0; i < buffer.length; i++) - { - if (i == gapStart) - System.err.print('<'); - if (i == gapEnd) - System.err.print('>'); - - if (!Character.isISOControl(buffer[i])) - System.err.print(buffer[i]); - else - System.err.print('.'); - } - System.err.println(); - } - - /** - * Prints out the position marks. - */ - private void dumpMarks() - { - System.out.print("positionMarks: "); - for (int i = 0; i < marks.size(); i++) - System.out.print(((Mark) marks.get(i)).mark + ", "); - System.out.println(); - } - - /** - * Searches the first occurance of object <code>o</code> in list - * <code>l</code>. This performs a binary search by calling - * {@link Collections#binarySearch(List, Object)} and when an object has been - * found, it searches backwards to the first occurance of that object in the - * list. The meaning of the return value is the same as in - * <code>Collections.binarySearch()</code>. - * - * @param o the object to be searched - * - * @return the index of the first occurance of o in l, or -i + 1 if not found - */ - int search(Mark o) - { - int foundInd = 0; - boolean found = false; - int low = 0; - int up = marks.size() - 1; - int mid = 0; - if (up > -1) - { - int cmp = 0; - Mark last = (Mark) marks.get(up); - cmp = compare(o, last); - if (cmp > 0) - { - foundInd = up + 1; - found = true; - } - else - { - while (low <= up && ! found) - { - mid = low + (up - low) / 2; - Mark m = (Mark) marks.get(mid); - cmp = compare(o, m); - if (cmp == 0) - { - foundInd = mid; - found = true; - } - else if (cmp < 0) - up = mid - 1; - else - low = mid + 1; - } - - if (! found) - foundInd = cmp < 0 ? mid : mid + 1; - } - } - return foundInd; - } - - private int searchFirst(int index) - { - searchMark.mark = Math.max(index, 1); - int i = search(searchMark); - for (int j = i - 1; j >= 0; j--) - { - Mark m = (Mark) marks.get(j); - if (m.mark != index) - break; - i--; - } - return i; - } - - /** - * Compares two marks. - * - * @param m1 the first mark - * @param m2 the second mark - * - * @return negative when m1 < m2, positive when m1 > m2 and 0 when equal - */ - private int compare(Mark m1, Mark m2) - { - return m1.mark - m2.mark; - } - - /** - * Collects and frees unused marks. - */ - private void garbageCollect() - { - int count = marks.size(); - ArrayList clean = new ArrayList(); - for (int i = 0; i < count; i++) - { - Mark m = (Mark) marks.get(i); - if (m.get() != null) - clean.add(m); - } - marks = clean; - garbageMarks = 0; - } -} |