1 /*
   2  * Copyright (c) 2015, 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 package java.lang.invoke;
  26 
  27 import java.nio.Buffer;
  28 import java.nio.ByteBuffer;
  29 
  30 import static java.lang.invoke.MethodHandleStatics.UNSAFE;
  31 
  32 /**
  33  * The base class for generated byte array and byte buffer view
  34  * implementations
  35  */
  36 abstract class VarHandleByteArrayBase {
  37     // Buffer.address
  38     static final long BUFFER_ADDRESS;
  39     // Buffer.limit
  40     static final long BUFFER_LIMIT;
  41     // ByteBuffer.hb
  42     static final long BYTE_BUFFER_HB;
  43     // ByteBuffer.isReadOnly
  44     static final long BYTE_BUFFER_IS_READ_ONLY;
  45 
  46     static {
  47         try {
  48             BUFFER_ADDRESS = UNSAFE.objectFieldOffset(
  49                     Buffer.class.getDeclaredField("address"));
  50 
  51             BUFFER_LIMIT = UNSAFE.objectFieldOffset(
  52                     Buffer.class.getDeclaredField("limit"));
  53 
  54             BYTE_BUFFER_HB = UNSAFE.objectFieldOffset(
  55                     ByteBuffer.class.getDeclaredField("hb"));
  56 
  57             BYTE_BUFFER_IS_READ_ONLY = UNSAFE.objectFieldOffset(
  58                     ByteBuffer.class.getDeclaredField("isReadOnly"));
  59         }
  60         catch (ReflectiveOperationException e) {
  61             throw new Error(e);
  62         }
  63     }
  64 
  65     static final boolean BE = UNSAFE.isBigEndian();
  66 
  67     static IllegalStateException newIllegalStateExceptionForMisalignedAccess(int index) {
  68         return new IllegalStateException("Misaligned access at index: " + index);
  69     }
  70 }