1 /*
   2  * Copyright (c) 2019, 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.lang.invoke;
  27 
  28 /**
  29  * Base class for memory access var handle implementations.
  30  */
  31 abstract class VarHandleMemoryAddressBase extends VarHandle {
  32 
  33     /** endianness **/
  34     final boolean be;
  35 
  36     /** access size (in bytes, computed from var handle carrier type) **/
  37     final long length;
  38 
  39     /** access offset (in bytes); must be compatible with {@code alignmentMask} **/
  40     final long offset;
  41 
  42     /** alignment constraint (in bytes, expressed as a bit mask) **/
  43     final long alignmentMask;
  44 
  45     VarHandleMemoryAddressBase(VarForm form, boolean be, long length, long offset, long alignmentMask) {
  46         super(form);
  47         this.be = be;
  48         this.length = length;
  49         this.offset = offset;
  50         this.alignmentMask = alignmentMask;
  51     }
  52 
  53     static IllegalStateException newIllegalStateExceptionForMisalignedAccess(long address) {
  54         return new IllegalStateException("Misaligned access at address: " + address);
  55     }
  56 
  57     /**
  58      * Strides used for multi-dimensional access; each stride must be compatible with {@code alignmentMask}.
  59      */
  60     abstract long[] strides();
  61 
  62     abstract Class<?> carrier();
  63 }