org.spearce.jgit/src/org/spearce/jgit/treewalk/filter/AndTreeFilter.java

   1 /*
   2  * Copyright (C) 2007, Robin Rosenberg <robin.rosenberg@dewire.com>
   3  * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
   4  *
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or
   8  * without modification, are permitted provided that the following
   9  * conditions are met:
  10  *
  11  * - Redistributions of source code must retain the above copyright
  12  *   notice, this list of conditions and the following disclaimer.
  13  *
  14  * - Redistributions in binary form must reproduce the above
  15  *   copyright notice, this list of conditions and the following
  16  *   disclaimer in the documentation and/or other materials provided
  17  *   with the distribution.
  18  *
  19  * - Neither the name of the Git Development Community nor the
  20  *   names of its contributors may be used to endorse or promote
  21  *   products derived from this software without specific prior
  22  *   written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  25  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  26  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  27  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  28  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  29  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  30  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  31  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  32  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  33  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  34  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  36  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  37  */
  38
  39 package org.spearce.jgit.treewalk.filter;
  40
  41 import java.io.IOException;
  42 import java.util.Collection;
  43
  44 import org.spearce.jgit.errors.IncorrectObjectTypeException;
  45 import org.spearce.jgit.errors.MissingObjectException;
  46 import org.spearce.jgit.treewalk.TreeWalk;
  47
  48 /**
  49  * Includes a tree entry only if all subfilters include the same tree entry.
  50  * <p>
  51  * Classic shortcut behavior is used, so evaluation of the
  52  * {@link TreeFilter#include(TreeWalk)} method stops as soon as a false result
  53  * is obtained. Applications can improve filtering performance by placing faster
  54  * filters that are more likely to reject a result earlier in the list.
  55  */
  56 public abstract class AndTreeFilter extends TreeFilter {
  57         /**
  58          * Create a filter with two filters, both of which must match.
  59          *
  60          * @param a
  61          *            first filter to test.
  62          * @param b
  63          *            second filter to test.
  64          * @return a filter that must match both input filters.
  65          */
  66         public static TreeFilter create(final TreeFilter a, final TreeFilter b) {
  67                 if (a == ALL)
  68                         return b;
  69                 if (b == ALL)
  70                         return a;
  71                 return new Binary(a, b);
  72         }
  73
  74         /**
  75          * Create a filter around many filters, all of which must match.
  76          *
  77          * @param list
  78          *            list of filters to match against. Must contain at least 2
  79          *            filters.
  80          * @return a filter that must match all input filters.
  81          */
  82         public static TreeFilter create(final TreeFilter[] list) {
  83                 if (list.length == 2)
  84                         return create(list[0], list[1]);
  85                 if (list.length < 2)
  86                         throw new IllegalArgumentException("At least two filters needed.");
  87                 final TreeFilter[] subfilters = new TreeFilter[list.length];
  88                 System.arraycopy(list, 0, subfilters, 0, list.length);
  89                 return new List(subfilters);
  90         }
  91
  92         /**
  93          * Create a filter around many filters, all of which must match.
  94          *
  95          * @param list
  96          *            list of filters to match against. Must contain at least 2
  97          *            filters.
  98          * @return a filter that must match all input filters.
  99          */
 100         public static TreeFilter create(final Collection<TreeFilter> list) {
 101                 if (list.size() < 2)
 102                         throw new IllegalArgumentException("At least two filters needed.");
 103                 final TreeFilter[] subfilters = new TreeFilter[list.size()];
 104                 list.toArray(subfilters);
 105                 if (subfilters.length == 2)
 106                         return create(subfilters[0], subfilters[1]);
 107                 return new List(subfilters);
 108         }
 109
 110         private static class Binary extends AndTreeFilter {
 111                 private final TreeFilter a;
 112
 113                 private final TreeFilter b;
 114
 115                 Binary(final TreeFilter one, final TreeFilter two) {
 116                         a = one;
 117                         b = two;
 118                 }
 119
 120                 @Override
 121                 public boolean include(final TreeWalk walker)
 122                                 throws MissingObjectException, IncorrectObjectTypeException,
 123                                 IOException {
 124                         return a.include(walker) && b.include(walker);
 125                 }
 126
 127                 @Override
 128                 public boolean shouldBeRecursive() {
 129                         return a.shouldBeRecursive() || b.shouldBeRecursive();
 130                 }
 131
 132                 @Override
 133                 public TreeFilter clone() {
 134                         return new Binary(a.clone(), b.clone());
 135                 }
 136
 137                 @Override
 138                 public String toString() {
 139                         return "(" + a.toString() + " AND " + b.toString() + ")";
 140                 }
 141         }
 142
 143         private static class List extends AndTreeFilter {
 144                 private final TreeFilter[] subfilters;
 145
 146                 List(final TreeFilter[] list) {
 147                         subfilters = list;
 148                 }
 149
 150                 @Override
 151                 public boolean include(final TreeWalk walker)
 152                                 throws MissingObjectException, IncorrectObjectTypeException,
 153                                 IOException {
 154                         for (final TreeFilter f : subfilters) {
 155                                 if (!f.include(walker))
 156                                         return false;
 157                         }
 158                         return true;
 159                 }
 160
 161                 @Override
 162                 public boolean shouldBeRecursive() {
 163                         for (final TreeFilter f : subfilters)
 164                                 if (f.shouldBeRecursive())
 165                                         return true;
 166                         return false;
 167                 }
 168
 169                 @Override
 170                 public TreeFilter clone() {
 171                         final TreeFilter[] s = new TreeFilter[subfilters.length];
 172                         for (int i = 0; i < s.length; i++)
 173                                 s[i] = subfilters[i].clone();
 174                         return new List(s);
 175                 }
 176
 177                 @Override
 178                 public String toString() {
 179                         final StringBuffer r = new StringBuffer();
 180                         r.append("(");
 181                         for (int i = 0; i < subfilters.length; i++) {
 182                                 if (i > 0)
 183                                         r.append(" AND ");
 184                                 r.append(subfilters[i].toString());
 185                         }
 186                         r.append(")");
 187                         return r.toString();
 188                 }
 189         }
 190 }