Data-Structures/LinkedListTest.java at master · mchao409/Data-Structures · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
import static org.junit.Assert.*;

import org.junit.Test;

public class LinkedListTest {

  @Test
  public void testAddAtEnd() {
    LinkedList<String> list = new LinkedList<String>();
    list.add("hello");
    assertTrue(list.getHead().getContents().equals("hello"));
    list.add("apple");
    assertTrue(list.getHead().getNext().getContents().equals("apple"));
  }

  @Test
  public void testAddAtIndex() {
    LinkedList<Integer> list = new LinkedList<Integer>();
    list.add(0,1); list.add(1,2); list.add(2,100);
    list.add(0,10); list.add(1,3);
    assertTrue(list.getHead().getContents() == 10);
    assertTrue(list.getHead().getNext().getContents() == 3);
    assertTrue(list.getHead().getNext().getNext().getContents() == 1);
    assertTrue(list.getHead().getNext().getNext().getNext().getContents() == 2);
    assertTrue(list.getHead().getNext().getNext().getNext().getNext().getContents() == 100);

  }

  @Test
  public void testClear() {
    LinkedList<Integer> list = new LinkedList<Integer>();
    list.clear();
    assertTrue(list.head == null);

    list.add(10);
    list.clear();
    assertTrue(list.head == null);

    for(int i = 0 ; i < 100; i++) {
      list.add(i);
    }
    list.clear();
    assertTrue(list.head == null);
  }

  @Test
  public void testRemoveIndex() {
    LinkedList<Integer> list = new LinkedList<Integer>();
    try {
      list.remove(10);
      fail();
    } catch (NullPointerException e) {}
    list.add(1);

    try {
      list.remove(2);
      fail();
    } catch (NullPointerException e) {}
    assertTrue(list.remove(0) == 1);

    for(int i = 0; i < 10; i++) {
      list.add(i);
    }
    assertTrue(list.remove(9) == 9);

    try {
      list.remove(9);
      fail();
    } catch (NullPointerException e) {}

    for(int i = 8; i >= 0; i--) {
      assertTrue(list.remove(i) == i);
    }
  }

  @Test
  public void testRemoveObject() {
    LinkedList<String> list = new LinkedList<String>();
    assertFalse(list.remove("apple"));

    String[] words = {"apple","apple","pear", "blueberry","banana", "apple"};
    for(int i = 0; i < words.length; i++) {
      list.add(words[i]);
    }
    list.remove("apple");
    assertTrue(list.getHead().getContents().equals("apple"));
    list.remove("apple");
    assertTrue(list.getHead().getNext().getNext()
        .getNext().getNext().getNext().getContents().equals("apple"));
    assertTrue(list.contains("apple"));
    for(int i = 2; i < words.length; i++) {
      assertTrue(list.remove(words[i]));
    }

  }

  @Test
  public void testContains() {
    LinkedList<Integer> list = new LinkedList<Integer>();
    assertFalse(list.contains(10));
    list.add(100);
    assertTrue(list.contains(100));
    list.remove(0);
    assertFalse(list.contains(100));
    for(int i = 0; i < 100; i++) {
      list.add(i);
      assertTrue(list.contains(i));
    }
    for(int i = 99; i >= 0; i--) {
      list.remove(i);
      assertFalse(list.contains(i));
    }
  }

  @Test
  public void testSize() {
    LinkedList<Integer> list = new LinkedList<Integer>();
    assertTrue(list.size() == 0);
    list.add(0);
    assertTrue(list.size() == 1);
    list.remove(0);
    assertTrue(list.size() == 0);
    for(int i = 0; i < 100; i++) {
      list.add(i);
      assertTrue(list.size() == i+1);
    }
    for(int i = 99; i >= 0; i--) {
      list.remove(i);
      assertTrue(list.size() == i);
    }
  }
}