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1
30
31
32 package org.hsqldb.lib;
33
34 import java.util.NoSuchElementException  ;
35
36
43 abstract class BaseList {
44
45 protected int elementCount;
46
47 abstract Object get(int index);
48
49 abstract Object remove(int index);
50
51 abstract boolean add(Object o);
52
53 abstract int size();
54
55 public boolean contains(Object o) {
56 return find(o) == -1 ? false
57 : true;
58 }
59
60 public boolean remove(Object o) {
61
62 int i = find(o);
63
64 if (i == -1) {
65 return false;
66 }
67
68 remove(i);
69
70 return true;
71 }
72
73 int find(Object o) {
74
75 for (int i = 0, size = size(); i < size; i++) {
76 Object current = get(i);
77
78 if (current == null) {
79 if (o == null) {
80 return i;
81 }
82 } else if (current.equals(o)) {
83 return i;
84 }
85 }
86
87 return -1;
88 }
89
90 public boolean addAll(Collection other) {
91
92 boolean result = false;
93 Iterator it = other.iterator();
94
95 while (it.hasNext()) {
96 result = true;
97
98 add(it.next());
99 }
100
101 return result;
102 }
103
104 public boolean isEmpty() {
105 return elementCount == 0;
106 }
107
108
109 public String toString() {
110
111 StringBuffer sb = new StringBuffer (32 + elementCount * 3);
112
113 sb.append("List : size=");
114 sb.append(elementCount);
115 sb.append(' ');
116 sb.append('{');
117
118 Iterator it = iterator();
119
120 while (it.hasNext()) {
121 sb.append(it.next());
122
123 if (it.hasNext()) {
124 sb.append(',');
125 sb.append(' ');
126 }
127 }
128
129 sb.append('}');
130
131 return sb.toString();
132 }
133
134 public Iterator iterator() {
135 return new BaseListIterator();
136 }
137
138 private class BaseListIterator implements Iterator {
139
140 int counter = 0;
141 boolean removed;
142
143 public boolean hasNext() {
144 return counter < elementCount;
145 }
146
147 public Object next() {
148
149 if (counter < elementCount) {
150 removed = false;
151
152 Object returnValue = get(counter);
153
154 counter++;
155
156 return returnValue;
157 }
158
159 throw new NoSuchElementException ();
160 }
161
162 public int nextInt() {
163 throw new NoSuchElementException ();
164 }
165
166 public long nextLong() {
167 throw new NoSuchElementException ();
168 }
169
170 public void remove() {
171
172 if (removed) {
173 throw new NoSuchElementException ("Iterator");
174 }
175
176 removed = true;
177
178 if (counter != 0) {
179 BaseList.this.remove(counter - 1);
180
181 counter--;
183 return;
184 }
185
186 throw new NoSuchElementException ();
187 }
188 }
189 }
190 |
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