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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.juneau.commons.function;
18  
19  import static org.apache.juneau.TestUtils.assertThrowsWithMessage;
20  import static org.junit.jupiter.api.Assertions.*;
21  
22  import java.util.function.*;
23  
24  import org.apache.juneau.*;
25  import org.junit.jupiter.api.*;
26  
27  class Function4_Test extends TestBase {
28  
29  	//------------------------------------------------------------------------------------------------------------------
30  	// Basic tests.
31  	//------------------------------------------------------------------------------------------------------------------
32  	@Test void a01_basic() {
33  		Function4<Integer,Integer,Integer,Integer,Integer> x = (a,b,c,d)->a+b+c+d;
34  		assertEquals(10, x.apply(1,2,3,4));
35  	}
36  
37  	@Test void a02_withNullValues() {
38  		Function4<String,Integer,Boolean,Double,String> x = (a, b, c, d) -> a + b + c + d;
39  		assertEquals("null42true3.14", x.apply(null, 42, true, 3.14));
40  		assertEquals("foo0nullnull", x.apply("foo", 0, null, null));
41  		assertEquals("nullnullnullnull", x.apply(null, null, null, null));
42  	}
43  
44  	@Test void a03_returnsNull() {
45  		Function4<String,Integer,Boolean,Double,String> x = (a, b, c, d) -> null;
46  		assertNull(x.apply("foo", 42, true, 3.14));
47  	}
48  
49  	//------------------------------------------------------------------------------------------------------------------
50  	// andThen tests.
51  	//------------------------------------------------------------------------------------------------------------------
52  	@Test void b01_andThen_basic() {
53  		Function4<Integer,Integer,Integer,Integer,Integer> first = (a, b, c, d) -> a + b + c + d;
54  		Function<Integer,String> after = x -> "result: " + x;
55  		Function4<Integer,Integer,Integer,Integer,String> composed = first.andThen(after);
56  
57  		assertEquals("result: 10", composed.apply(1, 2, 3, 4));
58  	}
59  
60  	@Test void b02_andThen_differentReturnType() {
61  		Function4<String,Integer,Boolean,Double,Integer> first = (a, b, c, d) -> a.length() + b + (c ? 1 : 0) + (int)d.doubleValue();
62  		Function<Integer,Boolean> after = x -> x > 10;
63  		Function4<String,Integer,Boolean,Double,Boolean> composed = first.andThen(after);
64  
65  		assertTrue(composed.apply("hello", 1, true, 5.0));   // 5 + 1 + 1 + 5 = 12 > 10
66  		assertFalse(composed.apply("hi", 1, false, 1.0));    // 2 + 1 + 0 + 1 = 4 <= 10
67  	}
68  
69  	@Test void b03_andThen_chaining() {
70  		Function4<Integer,Integer,Integer,Integer,Integer> first = (a, b, c, d) -> a + b + c + d;
71  		Function<Integer,Integer> second = x -> x * 2;
72  		Function<Integer,String> third = x -> "value: " + x;
73  		Function4<Integer,Integer,Integer,Integer,String> composed = first.andThen(second).andThen(third);
74  
75  		assertEquals("value: 20", composed.apply(1, 2, 3, 4));  // (1+2+3+4)*2 = 20
76  	}
77  
78  	@Test void b04_andThen_withNullAfter() {
79  		Function4<Integer,Integer,Integer,Integer,Integer> first = (a, b, c, d) -> a + b + c + d;
80  		assertThrowsWithMessage(IllegalArgumentException.class, "Argument 'after' cannot be null", () -> {
81  			first.andThen(null);
82  		});
83  	}
84  
85  	@Test void b05_andThen_afterReturnsNull() {
86  		Function4<Integer,Integer,Integer,Integer,Integer> first = (a, b, c, d) -> a + b + c + d;
87  		Function<Integer,String> after = x -> null;
88  		Function4<Integer,Integer,Integer,Integer,String> composed = first.andThen(after);
89  
90  		assertNull(composed.apply(1, 2, 3, 4));
91  	}
92  }