1 /*
   2  * Copyright (c) 2018, 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.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test
  26  * @bug 8206986 8214114 8214529
  27  * @summary Verify various corner cases with nested switch expressions.
  28  * @compile ExpressionSwitchBugs.java
  29  * @run main ExpressionSwitchBugs
  30  */
  31 
  32 public class ExpressionSwitchBugs {
  33     public static void main(String... args) {
  34         new ExpressionSwitchBugs().testNested();
  35         new ExpressionSwitchBugs().testAnonymousClasses();
  36         new ExpressionSwitchBugs().testFields();
  37         check(3, new C(-1, 3).test(false));
  38         check(3, new C(3, -1).test(true));
  39     }
  40 
  41     private void testNested() {
  42         int i = 0;
  43         check(42, id(switch (42) {
  44             default: i++; yield 42;
  45         }));
  46         i = 0;
  47         check(43, id(switch (42) {
  48             case 42: while (i == 0) {
  49                 i++;
  50             }
  51             yield 42 + i;
  52             default: i++; yield 42;
  53         }));
  54         i = 0;
  55         check(42, id(switch (42) {
  56             case 42: if (i == 0) {
  57                 yield 42;
  58             }
  59             default: i++; yield 43;
  60         }));
  61         i = 0;
  62         check(42, id(switch (42) {
  63             case 42: if (i == 0) {
  64                 yield 41 + switch (0) {
  65                     case 0 -> 1;
  66                     default -> -1;
  67                 };
  68             }
  69             default: i++; yield 43;
  70         }));
  71     }
  72 
  73     private void testAnonymousClasses() {
  74         for (int i : new int[] {1, 2}) {
  75             check(3, id((switch (i) {
  76                 case 1: yield new I() {
  77                     public int g() { return 3; }
  78                 };
  79                 default: yield (I) () -> { return 3; };
  80             }).g()));
  81             check(3, id((switch (i) {
  82                 case 1 -> new I() {
  83                     public int g() { return 3; }
  84                 };
  85                 default -> (I) () -> { return 3; };
  86             }).g()));
  87         }
  88     }
  89 
  90     private void testFields() {
  91         check(3, field);
  92         check(3, ExpressionSwitchBugs.staticField);
  93     }
  94 
  95     private final int value = 2;
  96     private final int field = id(switch(value) {
  97         case 0 -> -1;
  98         case 2 -> {
  99             int temp = 0;
 100             temp += 3;
 101             yield temp;
 102         }
 103         default -> throw new IllegalStateException();
 104     });
 105 
 106     private static final int staticValue = 2;
 107     private static final int staticField = new ExpressionSwitchBugs().id(switch(staticValue) {
 108         case 0 -> -1;
 109         case 2 -> {
 110             int temp = 0;
 111             temp += 3;
 112             yield temp;
 113         }
 114         default -> throw new IllegalStateException();
 115     });
 116 
 117     private int id(int i) {
 118         return i;
 119     }
 120 
 121     private int id(Object o) {
 122         return -1;
 123     }
 124 
 125     private static void check(int actual, int expected) {
 126         if (actual != expected) {
 127             throw new AssertionError("Unexpected result: " + actual);
 128         }
 129     }
 130 
 131     public interface I {
 132         public int g();
 133     }
 134 
 135     static class Super {
 136         public final int i;
 137 
 138         public Super(int i) {
 139             this.i = i;
 140         }
 141 
 142     }
 143     static class C extends Super {
 144         public final int i;
 145 
 146         public C(int superI, int i) {
 147             super(superI);
 148             this.i = i;
 149         }
 150 
 151         public int test(boolean fromSuper) {
 152             return switch (fromSuper ? 0 : 1) {
 153                 case 0 -> {
 154                     yield super.i;
 155                 }
 156                 default -> {
 157                     yield this.i;
 158                 }
 159             };
 160         }
 161     }
 162 }