| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.thrift; |
| |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.Collection; |
| import java.util.HashSet; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Set; |
| |
| /** |
| * IntRangeSet is a specialized Set<Integer> implementation designed |
| * specifically to make the generated validate() method calls faster. It groups |
| * the set values into ranges, and in the contains() call, it does |
| * num ranges * 2 comparisons max. For the common case, which is a single, |
| * contiguous range, this approach is about 60% faster than using a HashSet. If |
| * you had a very ragged value set, like all the odd numbers, for instance, |
| * then you would end up with pretty poor running time. |
| */ |
| public class IntRangeSet implements Set<Integer> { |
| /** |
| * This array keeps the bounds of each extent in alternating cells, always |
| * increasing. Example: [0,5,10,15], which corresponds to 0-5, 10-15. |
| */ |
| private int[] extents; |
| |
| /** |
| * We'll keep a duplicate, real HashSet around internally to satisfy some of |
| * the other set operations. |
| */ |
| private Set<Integer> realSet = new HashSet<Integer>(); |
| |
| public IntRangeSet(int... values) { |
| Arrays.sort(values); |
| |
| List<Integer> extent_list = new ArrayList<Integer>(); |
| |
| int ext_start = values[0]; |
| int ext_end_so_far = values[0]; |
| for (int i = 1; i < values.length; i++) { |
| realSet.add(values[i]); |
| |
| if (values[i] == ext_end_so_far + 1) { |
| // advance the end so far |
| ext_end_so_far = values[i]; |
| } else { |
| // create an extent for everything we saw so far, move on to the next one |
| extent_list.add(ext_start); |
| extent_list.add(ext_end_so_far); |
| ext_start = values[i]; |
| ext_end_so_far = values[i]; |
| } |
| } |
| extent_list.add(ext_start); |
| extent_list.add(ext_end_so_far); |
| |
| extents = new int[extent_list.size()]; |
| for (int i = 0; i < extent_list.size(); i++) { |
| extents[i] = extent_list.get(i); |
| } |
| } |
| |
| public boolean add(Integer i) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public void clear() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public boolean addAll(Collection<? extends Integer> arg0) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** |
| * While this method is here for Set interface compatibility, you should avoid |
| * using it. It incurs boxing overhead! Use the int method directly, instead. |
| */ |
| public boolean contains(Object arg0) { |
| return contains(((Integer)arg0).intValue()); |
| } |
| |
| /** |
| * This is much faster, since it doesn't stop at Integer on the way through. |
| * @param val the value you want to check set membership for |
| * @return true if val was found, false otherwise |
| */ |
| public boolean contains(int val) { |
| for (int i = 0; i < extents.length / 2; i++) { |
| if (val < extents[i*2]) { |
| return false; |
| } else if (val <= extents[i*2+1]) { |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| public boolean containsAll(Collection<?> arg0) { |
| for (Object o : arg0) { |
| if (!contains(o)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| public boolean isEmpty() { |
| return realSet.isEmpty(); |
| } |
| |
| public Iterator<Integer> iterator() { |
| return realSet.iterator(); |
| } |
| |
| public boolean remove(Object arg0) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public boolean removeAll(Collection<?> arg0) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public boolean retainAll(Collection<?> arg0) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public int size() { |
| return realSet.size(); |
| } |
| |
| public Object[] toArray() { |
| return realSet.toArray(); |
| } |
| |
| public <T> T[] toArray(T[] arg0) { |
| return realSet.toArray(arg0); |
| } |
| |
| @Override |
| public String toString() { |
| String buf = ""; |
| for (int i = 0; i < extents.length / 2; i++) { |
| if (i != 0) { |
| buf += ", "; |
| } |
| buf += "[" + extents[i*2] + "," + extents[i*2+1] + "]"; |
| } |
| return buf; |
| } |
| } |