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      1 // Copyright (c) 2016, the R8 project authors. Please see the AUTHORS file
      2 // for details. All rights reserved. Use of this source code is governed by a
      3 // BSD-style license that can be found in the LICENSE file.
      4 
      5 // This code is not run directly. It needs to be compiled to dex code.
      6 // 'switches.dex' is what is run.
      7 
      8 package switches;
      9 
     10 class Switches {
     11 
     12   public static void packedSwitch(int value) {
     13     System.out.print("packedSwitch cases: ");
     14     switch (value) {
     15       case 0:
     16         System.out.print("0 ");
     17       case 1:
     18       case 2:
     19         System.out.print("1 2 ");
     20         break;
     21       case 3:
     22         System.out.print("3 ");
     23         break;
     24     }
     25     System.out.println("after switch " + value);
     26   }
     27 
     28   public static void sparseSwitch(int value) {
     29     switch (value) {
     30       case 0:
     31         System.out.println("0 ");
     32       case 100:
     33         System.out.println("100 ");
     34         break;
     35       case 200:
     36         System.out.println("200 ");
     37         break;
     38     }
     39     System.out.println("after switch " + value);
     40   }
     41 
     42   public static void switchWithLocals(int value) {
     43     switch (value) {
     44       case 0: {
     45         int i = 42;
     46         System.out.println(" " + i + value);
     47         break;
     48       }
     49       case 2: {
     50         double d = 1.0;
     51         System.out.println(" " + d + value);
     52         break;
     53       }
     54     }
     55   }
     56 
     57   public static void maybePackedSwitch(int value) {
     58     switch (value) {
     59       case 0:
     60       case 1:
     61       case 2:
     62       case 3:
     63       case 4:
     64       case 5:
     65       case 6:
     66       case 7:
     67       case 8:
     68       case 10:
     69       case 11:
     70       case 12:
     71       case 13:
     72       case 14:
     73       case 15:
     74       case 16:
     75       case 17:
     76       case 18:
     77       case 19:
     78       case 20:
     79       case 21:
     80         System.out.print("0-21 ");
     81         break;
     82       case 60:
     83         System.out.print("60 ");
     84         break;
     85     }
     86     System.out.println("after switch " + value);
     87   }
     88 
     89   public static void main(String[] args) {
     90     packedSwitch(0);
     91     packedSwitch(1);
     92     packedSwitch(2);
     93     packedSwitch(-1);  // No such case, use fallthrough.
     94     sparseSwitch(0);
     95     sparseSwitch(100);
     96     sparseSwitch(200);
     97     sparseSwitch(-1);  // No such case, use fallthrough.
     98     switchWithLocals(0);
     99     switchWithLocals(2);
    100     maybePackedSwitch(1);
    101     maybePackedSwitch(10);
    102     maybePackedSwitch(40);  // Fallthrough.
    103     maybePackedSwitch(60);
    104   }
    105 }
    106