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 package java.foreign.layout;
  26 
  27 import java.util.Map;
  28 
  29 /**
  30  * A padding layout specifies the size of extra space used to align struct fields around word boundaries.
  31  */
  32 public class Padding extends AbstractDescriptor<Padding> implements Layout {
  33     private final long size;
  34 
  35     Padding(long size, Map<String, String> annotations) {
  36         super(annotations);
  37         this.size = size;
  38     }
  39 
  40     /**
  41      * Create a new selector layout from given path expression.
  42      * @param size the padding size in bits.
  43      * @return the new selector layout.
  44      */
  45     public static Padding of(long size) {
  46         return new Padding(size, NO_ANNOS);
  47     }
  48 
  49     @Override
  50     public long bitsSize() {
  51         return size;
  52     }
  53 
  54     @Override
  55     public boolean isPartial() {
  56         return false;
  57     }
  58 
  59     @Override
  60     public String toString() {
  61         return wrapWithAnnotations("x" + size);
  62     }
  63 
  64     @Override
  65     public boolean equals(Object other) {
  66         if (this == other) {
  67             return true;
  68         }
  69         if (!super.equals(other)) {
  70             return false;
  71         }
  72         if (!(other instanceof Padding)) {
  73             return false;
  74         }
  75         Padding p = (Padding)other;
  76         return size == p.size;
  77     }
  78 
  79     @Override
  80     public int hashCode() {
  81         return super.hashCode() ^ Long.hashCode(size);
  82     }
  83 
  84     @Override
  85     Padding withAnnotations(Map<String, String> annotations) {
  86         return new Padding(size, annotations);
  87     }
  88 }