1 /*
2  * Copyright (C) 2010 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package libcore.io;
18 
19 import libcore.io.Memory;
20 
21 /**
22  * Iterates over big- or little-endian bytes on the native heap.
23  * See {@link MemoryMappedFile#bigEndianIterator} and {@link MemoryMappedFile#littleEndianIterator}.
24  *
25  * @hide don't make this public without adding bounds checking.
26  */
27 public final class NioBufferIterator extends BufferIterator {
28     private final long address;
29     private final int size;
30     private final boolean swap;
31 
32     private int position;
33 
NioBufferIterator(long address, int size, boolean swap)34     NioBufferIterator(long address, int size, boolean swap) {
35         this.address = address;
36         this.size = size;
37         this.swap = swap;
38     }
39 
seek(int offset)40     public void seek(int offset) {
41         position = offset;
42     }
43 
skip(int byteCount)44     public void skip(int byteCount) {
45         position += byteCount;
46     }
47 
readByteArray(byte[] dst, int dstOffset, int byteCount)48     public void readByteArray(byte[] dst, int dstOffset, int byteCount) {
49         Memory.peekByteArray(address + position, dst, dstOffset, byteCount);
50         position += byteCount;
51     }
52 
readByte()53     public byte readByte() {
54         byte result = Memory.peekByte(address + position);
55         ++position;
56         return result;
57     }
58 
readInt()59     public int readInt() {
60         int result = Memory.peekInt(address + position, swap);
61         position += SizeOf.INT;
62         return result;
63     }
64 
readIntArray(int[] dst, int dstOffset, int intCount)65     public void readIntArray(int[] dst, int dstOffset, int intCount) {
66         Memory.peekIntArray(address + position, dst, dstOffset, intCount, swap);
67         position += SizeOf.INT * intCount;
68     }
69 
readShort()70     public short readShort() {
71         short result = Memory.peekShort(address + position, swap);
72         position += SizeOf.SHORT;
73         return result;
74     }
75 }
76