1 /*
   2  * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8 * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package java.nio;
  27 
  28 import java.util.Comparator;
  29 import java.util.Spliterator;
  30 import java.util.function.IntConsumer;
  31 
  32 /**
  33  * A Spliterator.OfInt for sources that traverse and split elements
  34  * maintained in a CharBuffer.
  35  *
  36  * @implNote
  37  * The implementation is based on the code for the Array-based spliterators.
  38  */
  39 class CharBufferSpliterator implements Spliterator.OfInt {
  40     private final CharBuffer buffer;
  41     private int index;   // current index, modified on advance/split
  42     private final int limit;
  43 
  44     CharBufferSpliterator(CharBuffer buffer) {
  45         this(buffer, buffer.position(), buffer.limit());
  46     }
  47 
  48     CharBufferSpliterator(CharBuffer buffer, int origin, int limit) {
  49         assert origin <= limit;
  50         this.buffer = buffer;
  51         this.index = (origin <= limit) ? origin : limit;
  52         this.limit = limit;
  53     }
  54 
  55     @Override
  56     public OfInt trySplit() {
  57         int lo = index, mid = (lo + limit) >>> 1;
  58         return (lo >= mid)
  59                ? null
  60                : new CharBufferSpliterator(buffer, lo, index = mid);
  61     }
  62 
  63     @Override
  64     public void forEachRemaining(IntConsumer action) {
  65         if (action == null)
  66             throw new NullPointerException();
  67         CharBuffer cb = buffer;
  68         int i = index;
  69         int hi = limit;
  70         index = hi;
  71         while (i < hi) {
  72             action.accept(cb.getUnchecked(i++));
  73         }
  74     }
  75 
  76     @Override
  77     public boolean tryAdvance(IntConsumer action) {
  78         if (action == null)
  79             throw new NullPointerException();
  80         if (index >= 0 && index < limit) {
  81             action.accept(buffer.getUnchecked(index++));
  82             return true;
  83         }
  84         return false;
  85     }
  86 
  87     @Override
  88     public long estimateSize() {
  89         return (long)(limit - index);
  90     }
  91 
  92     @Override
  93     public int characteristics() {
  94         return Buffer.SPLITERATOR_CHARACTERISTICS;
  95     }
  96 }