1 /*
   2  * Copyright (c) 2017, 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
  27  * @summary Check fall through in switch expressions.
  28  * @compile --enable-preview -source 13 ExpressionSwitchFallThrough1.java
  29  * @run main/othervm --enable-preview ExpressionSwitchFallThrough1
  30  */
  31 
  32 import java.util.Objects;
  33 
  34 public class ExpressionSwitchFallThrough1 {
  35     public static void main(String... args) {
  36         new ExpressionSwitchFallThrough1().test();
  37     }
  38 
  39     private void test() {
  40         assertEquals("01", printExprFallThrough(0));
  41         assertEquals("1", printExprFallThrough(1));
  42         assertEquals("other", printExprFallThrough(3));
  43         assertEquals("01", printStatementFallThrough(0));
  44         assertEquals("1", printStatementFallThrough(1));
  45         assertEquals("other", printStatementFallThrough(3));
  46     }
  47 
  48     private String printExprFallThrough(Integer p) {
  49         String result = "";
  50         return switch (p) {
  51             case 0: result += "0";
  52             case 1: result += "1";
  53                 break result;
  54             default: break "other";
  55         };
  56     }
  57 
  58     private String printStatementFallThrough(Integer p) {
  59         String result = "";
  60         switch (p) {
  61             case 0: result += "0";
  62             case 1: result += "1";
  63                 break ;
  64             default: result = "other";
  65                 break;
  66         }
  67         return result;
  68     }
  69 
  70     private static void assertEquals(Object expected, Object actual) {
  71         if (!Objects.equals(actual, expected)) {
  72             throw new AssertionError("Unexpected result: " + actual + ", expected: " + expected);
  73         }
  74     }
  75 }