1 /*
 2  * Copyright (c) 2019, 2022, 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 import jdk.internal.foreign.Utils;
29 
30 /**
31  * Base class for memory segment var handle view implementations.
32  */
33 abstract sealed class VarHandleSegmentViewBase extends VarHandle permits
34         VarHandleSegmentAsBytes,
35         VarHandleSegmentAsChars,
36         VarHandleSegmentAsDoubles,
37         VarHandleSegmentAsFloats,
38         VarHandleSegmentAsInts,
39         VarHandleSegmentAsLongs,
40         VarHandleSegmentAsShorts {
41 
42     /** endianness **/
43     final boolean be;
44 
45     /** access size (in bytes, computed from var handle carrier type) **/
46     final long length;
47 
48     /** alignment constraint (in bytes, expressed as a bit mask) **/
49     final long alignmentMask;
50 
51     VarHandleSegmentViewBase(VarForm form, boolean be, long length, long alignmentMask, boolean exact) {
52         super(form, exact);
53         this.be = be;
54         this.length = length;
55         this.alignmentMask = alignmentMask;
56     }
57 
58     static IllegalArgumentException newIllegalArgumentExceptionForMisalignedAccess(long address) {
59         return new IllegalArgumentException("Misaligned access at address: " + Utils.toHexString(address));
60     }
61 
62     static UnsupportedOperationException newUnsupportedAccessModeForAlignment(long alignment) {
63         return new UnsupportedOperationException("Unsupported access mode for alignment: " + alignment);
64     }
65 }