1 /*
   2  * Copyright (c) 1999, 2005, 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 com.sun.tools.javac.util;
  27 


  28 /** A generic class for pairs.
  29  *
  30  *  <p><b>This is NOT part of any supported API.
  31  *  If you write code that depends on this, you do so at your own risk.
  32  *  This code and its internal interfaces are subject to change or
  33  *  deletion without notice.</b>
  34  */
  35 public class Pair<A, B> {
  36 
  37     public final A fst;
  38     public final B snd;
  39 
  40     public Pair(A fst, B snd) {
  41         this.fst = fst;
  42         this.snd = snd;
  43     }
  44 
  45     public String toString() {
  46         return "Pair[" + fst + "," + snd + "]";
  47     }
  48 
  49     private static boolean equals(Object x, Object y) {
  50         return (x == null && y == null) || (x != null && x.equals(y));
  51     }
  52 
  53     public boolean equals(Object other) {
  54         return
  55             other instanceof Pair<?,?> &&
  56             equals(fst, ((Pair<?,?>)other).fst) &&
  57             equals(snd, ((Pair<?,?>)other).snd);
  58     }
  59 
  60     public int hashCode() {
  61         if (fst == null) return (snd == null) ? 0 : snd.hashCode() + 1;
  62         else if (snd == null) return fst.hashCode() + 2;
  63         else return fst.hashCode() * 17 + snd.hashCode();
  64     }
  65 
  66     public static <A,B> Pair<A,B> of(A a, B b) {
  67         return new Pair<A,B>(a,b);
  68     }
  69 }

   1 /*
   2  * Copyright (c) 1999, 2013, 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 com.sun.tools.javac.util;
  27 
  28 import java.util.Objects;
  29 
  30 /** A generic class for pairs.
  31  *
  32  *  <p><b>This is NOT part of any supported API.
  33  *  If you write code that depends on this, you do so at your own risk.
  34  *  This code and its internal interfaces are subject to change or
  35  *  deletion without notice.</b>
  36  */
  37 public class Pair<A, B> {
  38 
  39     public final A fst;
  40     public final B snd;
  41 
  42     public Pair(A fst, B snd) {
  43         this.fst = fst;
  44         this.snd = snd;
  45     }
  46 
  47     public String toString() {
  48         return "Pair[" + fst + "," + snd + "]";
  49     }
  50 




  51     public boolean equals(Object other) {
  52         return
  53             other instanceof Pair<?,?> &&
  54             Objects.equals(fst, ((Pair<?,?>)other).fst) &&
  55             Objects.equals(snd, ((Pair<?,?>)other).snd);
  56     }
  57 
  58     public int hashCode() {
  59         if (fst == null) return (snd == null) ? 0 : snd.hashCode() + 1;
  60         else if (snd == null) return fst.hashCode() + 2;
  61         else return fst.hashCode() * 17 + snd.hashCode();
  62     }
  63 
  64     public static <A,B> Pair<A,B> of(A a, B b) {
  65         return new Pair<A,B>(a,b);
  66     }
  67 }