1 /*
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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
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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
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23 
24 /*
25  * @test
26  * @summary Unit tests for String#transform(Function<String, R> f)
27  * @run main Transform
28  */
29 
30 package test.java.lang.String;
31 
32 import java.util.function.Function;
33 import java.util.stream.Collectors;
34 
35 public class Transform {
main(String[] args)36     public static void main(String[] args) {
37         test1();
38     }
39 
40     /*
41      * Test String#transform(Function<? super String, ? extends R> f) functionality.
42      */
test1()43     static void test1() {
44         simpleTransform("toUpperCase", "abc", s -> s.toUpperCase());
45         simpleTransform("toLowerCase", "ABC", s -> s.toLowerCase());
46         simpleTransform("substring", "John Smith", s -> s.substring(0, 4));
47 
48         String multiline = "    This is line one\n" +
49                            "        This is line two\n" +
50                            "            This is line three\n";
51         String expected = "This is line one!\n" +
52                           "    This is line two!\n" +
53                           "        This is line three!\n";
54         check("multiline", multiline.transform(string -> {
55             return string.lines()
56                          .map(s -> s.transform(t -> t.substring(4) + "!"))
57                          .collect(Collectors.joining("\n", "", "\n"));
58         }), expected);
59     }
60 
simpleTransform(String test, String s, Function<String, String> f)61     static void simpleTransform(String test, String s, Function<String, String> f) {
62         check(test, s.transform(f), f.apply(s));
63     }
64 
check(String test, Object output, Object expected)65     static void check(String test, Object output, Object expected) {
66         if (output != expected && (output == null || !output.equals(expected))) {
67             System.err.println("Testing " + test + ": unexpected result");
68             System.err.println("Output:");
69             System.err.println(output);
70             System.err.println("Expected:");
71             System.err.println(expected);
72             throw new RuntimeException();
73         }
74     }
75 }
76