org.spearce.jgit/src/org/spearce/jgit/revwalk/DateRevQueue.java

   1 /*
   2  * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
   3  *
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or
   7  * without modification, are permitted provided that the following
   8  * conditions are met:
   9  *
  10  * - Redistributions of source code must retain the above copyright
  11  *   notice, this list of conditions and the following disclaimer.
  12  *
  13  * - Redistributions in binary form must reproduce the above
  14  *   copyright notice, this list of conditions and the following
  15  *   disclaimer in the documentation and/or other materials provided
  16  *   with the distribution.
  17  *
  18  * - Neither the name of the Git Development Community nor the
  19  *   names of its contributors may be used to endorse or promote
  20  *   products derived from this software without specific prior
  21  *   written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  24  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  25  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  26  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  28  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  29  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  30  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  31  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  32  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  33  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  35  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 package org.spearce.jgit.revwalk;
  39
  40 import java.io.IOException;
  41
  42 import org.spearce.jgit.errors.IncorrectObjectTypeException;
  43 import org.spearce.jgit.errors.MissingObjectException;
  44
  45 /** A queue of commits sorted by commit time order. */
  46 public class DateRevQueue extends AbstractRevQueue {
  47         private Entry head;
  48
  49         private Entry free;
  50
  51         /** Create an empty date queue. */
  52         public DateRevQueue() {
  53                 super();
  54         }
  55
  56         DateRevQueue(final Generator s) throws MissingObjectException,
  57                         IncorrectObjectTypeException, IOException {
  58                 for (;;) {
  59                         final RevCommit c = s.next();
  60                         if (c == null)
  61                                 break;
  62                         add(c);
  63                 }
  64         }
  65
  66         public void add(final RevCommit c) {
  67                 Entry q = head;
  68                 final long when = c.commitTime;
  69                 final Entry n = newEntry(c);
  70                 if (q == null || when > q.commit.commitTime) {
  71                         n.next = q;
  72                         head = n;
  73                 } else {
  74                         Entry p = q.next;
  75                         while (p != null && p.commit.commitTime > when) {
  76                                 q = p;
  77                                 p = q.next;
  78                         }
  79                         n.next = q.next;
  80                         q.next = n;
  81                 }
  82         }
  83
  84         public RevCommit next() {
  85                 final Entry q = head;
  86                 if (q == null)
  87                         return null;
  88                 head = q.next;
  89                 freeEntry(q);
  90                 return q.commit;
  91         }
  92
  93         /**
  94          * Peek at the next commit, without removing it.
  95          *
  96          * @return the next available commit; null if there are no commits left.
  97          */
  98         public RevCommit peek() {
  99                 return head != null ? head.commit : null;
 100         }
 101
 102         public void clear() {
 103                 head = null;
 104                 free = null;
 105         }
 106
 107         boolean everbodyHasFlag(final int f) {
 108                 for (Entry q = head; q != null; q = q.next) {
 109                         if ((q.commit.flags & f) == 0)
 110                                 return false;
 111                 }
 112                 return true;
 113         }
 114
 115         boolean anybodyHasFlag(final int f) {
 116                 for (Entry q = head; q != null; q = q.next) {
 117                         if ((q.commit.flags & f) != 0)
 118                                 return true;
 119                 }
 120                 return false;
 121         }
 122
 123         @Override
 124         int outputType() {
 125                 return outputType | SORT_COMMIT_TIME_DESC;
 126         }
 127
 128         public String toString() {
 129                 final StringBuffer s = new StringBuffer();
 130                 for (Entry q = head; q != null; q = q.next) {
 131                         s.append(q.commit);
 132                         s.append(' ');
 133                         s.append(q.commit.commitTime);
 134                         s.append('\n');
 135                 }
 136                 return s.toString();
 137         }
 138
 139         private Entry newEntry(final RevCommit c) {
 140                 Entry r = free;
 141                 if (r == null)
 142                         r = new Entry();
 143                 else
 144                         free = r.next;
 145                 r.commit = c;
 146                 return r;
 147         }
 148
 149         private void freeEntry(final Entry e) {
 150                 e.next = free;
 151                 free = e;
 152         }
 153
 154         static class Entry {
 155                 Entry next;
 156
 157                 RevCommit commit;
 158         }
 159 }