| /* |
| * Copyright 2000-2010 JetBrains s.r.o. |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package com.intellij.openapi.vcs; |
| |
| import com.intellij.openapi.util.Comparing; |
| import com.intellij.util.Consumer; |
| import com.intellij.util.PairConsumer; |
| import com.intellij.util.containers.ReadonlyList; |
| import com.intellij.util.containers.StepList; |
| |
| import java.util.Comparator; |
| |
| /** |
| * @author irengrig |
| * |
| * two group header can NOT immediately follow one another |
| */ |
| public abstract class GroupingMerger<T, S> { |
| private S myCurrentGroup; |
| |
| protected boolean filter(final T t) { |
| return true; |
| } |
| |
| protected abstract void willBeRecountFrom(int idx, int wasSize); |
| protected abstract S getGroup(final T t); |
| protected abstract T wrapGroup(final S s, T item); |
| protected abstract void oldBecame(final int was, final int is); |
| protected abstract void afterConsumed(final T t, int i); |
| protected T wrapItem(final T t) { |
| return t; |
| } |
| |
| public S getCurrentGroup() { |
| return myCurrentGroup; |
| } |
| |
| public int firstPlusSecond(final StepList<T> first, final ReadonlyList<T> second, final Comparator<T> comparator, |
| final int idxFrom) { |
| final int wasSize = first.getSize(); |
| if (second.getSize() == 0) { |
| return wasSize; |
| } |
| int idx; |
| if (idxFrom == -1) { |
| idx = stolenBinarySearch(first, second.get(0), comparator, 0); |
| if (idx < 0) { |
| idx = - (idx + 1); |
| } |
| } else { |
| idx = idxFrom; |
| } |
| // for group headers to not be left alone without its group |
| if (idx > 0 && (! filter(first.get(idx - 1)))) { |
| -- idx; |
| //if (idx > 0) --idx; // todo whether its ok |
| } |
| final ReadonlyList<T> remergePart = first.cut(idx); |
| if (idx > 0) { |
| myCurrentGroup = getGroup(first.get(idx - 1)); |
| } |
| final int finalIdx = idx; |
| willBeRecountFrom(idx, wasSize); |
| merge(remergePart, second, comparator, new PairConsumer<T, Integer>() { |
| @Override |
| public void consume(T t, Integer integer) { |
| doForGroup(t, first); |
| first.add(t); |
| int was = integer + finalIdx; |
| //System.out.println("was " + integer + "became " + (first.getSize() - 1)); |
| oldBecame(was, first.getSize() - 1); |
| } |
| }, new Consumer<T>() { |
| @Override |
| public void consume(T t) { |
| doForGroup(t, first); |
| |
| final T wrapped = wrapItem(t); |
| first.add(wrapped); |
| afterConsumed(wrapped, first.getSize() - 1); |
| } |
| }); |
| return idx; |
| } |
| |
| private void doForGroup(T t, StepList<T> first) { |
| final S newGroup = getGroup(t); |
| if (newGroup != null && ! Comparing.equal(newGroup, myCurrentGroup)) { |
| first.add(wrapGroup(newGroup, t)); |
| myCurrentGroup = newGroup; |
| } |
| } |
| |
| public void merge(final ReadonlyList<T> one, |
| final ReadonlyList<T> two, |
| final Comparator<T> comparator, |
| final PairConsumer<T, Integer> oldAdder, final Consumer<T> newAdder) { |
| int idx1 = 0; |
| int idx2 = 0; |
| while (idx1 < one.getSize() && idx2 < two.getSize()) { |
| final T firstOne = one.get(idx1); |
| if (! filter(firstOne)) { |
| ++ idx1; |
| continue; |
| } |
| final int comp = comparator.compare(firstOne, two.get(idx2)); |
| if (comp <= 0) { |
| oldAdder.consume(firstOne, idx1); |
| ++ idx1; |
| if (comp == 0) { |
| // take only one |
| ++ idx2; |
| } |
| } else { |
| newAdder.consume(two.get(idx2)); |
| ++ idx2; |
| } |
| } |
| while (idx1 < one.getSize()) { |
| final T firstOne = one.get(idx1); |
| if (! filter(firstOne)) { |
| ++ idx1; |
| continue; |
| } |
| oldAdder.consume(one.get(idx1), idx1); |
| ++ idx1; |
| } |
| while (idx2 < two.getSize()) { |
| newAdder.consume(two.get(idx2)); |
| ++ idx2; |
| } |
| } |
| |
| private static <T> int stolenBinarySearch(ReadonlyList<? extends T> l, T key, Comparator<? super T> c, final int from) { |
| int low = from; |
| int high = (l.getSize() - from) -1; |
| |
| while (low <= high) { |
| int mid = (low + high) >>> 1; |
| T midVal = l.get(mid); |
| int cmp = c.compare(midVal, key); |
| |
| if (cmp < 0) |
| low = mid + 1; |
| else if (cmp > 0) |
| high = mid - 1; |
| else |
| return mid; // key found |
| } |
| return -(low + 1); // key not found |
| } |
| } |