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author
shengshijun
committed
给部分方法添加有界通配符。
1 parent d70b5e9 commit aeb79ea

19 files changed

Lines changed: 58 additions & 57 deletions

‎src/main/java/ssj/algorithm/ArrayUtil.java‎

Lines changed: 19 additions & 18 deletions
Original file line numberDiff line numberDiff line change
@@ -92,15 +92,15 @@ public static <T> void reverse(T[] source, int start, int end) {
9292
}
9393
}
9494

95-
public static <T extends Comparable<T>> void sort(T[] arr) {
95+
public static <T extends Comparable<? super T>> void sort(T[] arr) {
9696
sort(Comparable::compareTo, arr, 0, arr.length - 1);
9797
}
9898

99-
public static <T> void sort(T[] arr, Comparator<T> comparator) {
99+
public static <T> void sort(T[] arr, Comparator<? super T> comparator) {
100100
sort(comparator, arr, 0, arr.length - 1);
101101
}
102102

103-
private static <T> void sort(Comparator<T> comparator, T[] arr, int start, int end) {
103+
private static <T> void sort(Comparator<? super T> comparator, T[] arr, int start, int end) {
104104
Preconditions.checkNotNull(arr, "arr should not be null");
105105
Preconditions.checkNotNull(comparator, "comparator should not be null");
106106
int length = end - start + 1;
@@ -113,11 +113,11 @@ private static <T> void sort(Comparator<T> comparator, T[] arr, int start, int e
113113
}
114114

115115

116-
private static <T extends Comparable<T>> int partition(T[] arr, int start, int end) {
116+
private static <T extends Comparable<? super T>> int partition(T[] arr, int start, int end) {
117117
return partition(Comparable::compareTo, arr, start, end);
118118
}
119119

120-
public static <T> int partition(Comparator<T> comparator, T[] arr, int start, int end) {
120+
public static <T> int partition(Comparator<? super T> comparator, T[] arr, int start, int end) {
121121
int par_index = MathUtil.randInt(start, end);
122122
ArrayUtil.swap(arr, start, par_index);
123123
par_index = start;
@@ -140,7 +140,7 @@ public static <T> int partition(Comparator<T> comparator, T[] arr, int start, in
140140
* @param <T>
141141
* @return
142142
*/
143-
public static <T extends Comparable<T>> T select(T[] arr, int k) {
143+
public static <T extends Comparable<? super T>> T select(T[] arr, int k) {
144144
Preconditions.checkNotNull(arr);
145145
Preconditions.checkPositionIndex(k, arr.length);
146146
int low = 0;
@@ -166,7 +166,7 @@ public static <T extends Comparable<T>> T select(T[] arr, int k) {
166166
* @param <T>
167167
* @return
168168
*/
169-
public <T extends Comparable<T>> int binarySearch(T[] arr, T ele) {
169+
public <T extends Comparable<? super T>> int binarySearch(T[] arr, T ele) {
170170
Preconditions.checkNotNull(arr);
171171
Preconditions.checkNotNull(ele);
172172
int low = 0;
@@ -192,13 +192,13 @@ public <T extends Comparable<T>> int binarySearch(T[] arr, T ele) {
192192
* @param comparator
193193
* @param <T>
194194
*/
195-
public static <T> void mergeSort(T[] arr, Comparator<T> comparator) {
195+
public static <T> void mergeSort(T[] arr, Comparator<? super T> comparator) {
196196
Preconditions.checkNotNull(arr);
197197
Preconditions.checkNotNull(comparator);
198198
mergeSort(arr, comparator, 0, arr.length - 1);
199199
}
200200

201-
private static <T> void mergeSort(T[] arr, Comparator<T> comparator, int start, int end) {
201+
private static <T> void mergeSort(T[] arr, Comparator<? super T> comparator, int start, int end) {
202202
if (start < end) {
203203
int middle = (end + start) / 2;
204204
mergeSort(arr, comparator, start, middle);
@@ -207,10 +207,11 @@ private static <T> void mergeSort(T[] arr, Comparator<T> comparator, int start,
207207
}
208208
}
209209

210-
private static <T> void merge(T[] arr, int start, int middle, int end, Comparator<T> comparator) {
210+
private static <T> void merge(T[] arr, int start, int middle, int end, Comparator<? super T> comparator) {
211211
int front_start = start;
212212
int end_start = middle + 1;
213213
int cur_pos = 0;
214+
@SuppressWarnings("unchecked")
214215
T[] helper = (T[]) new Object[end - start + 1];
215216
while (front_start <= middle && end_start <= end) {
216217
if (comparator.compare(arr[front_start], arr[end_start]) <= 0) {
@@ -256,7 +257,7 @@ public static void countSort(int[] arr, int start, int end) {
256257
System.arraycopy(result, 0, arr, 0, arr.length);
257258
}
258259

259-
public static <T> void radixSort(T[] arr, Comparator<T> comparator) {
260+
public static <T> void radixSort(T[] arr, Comparator<? extends T> comparator) {
260261
//todo 完成基数排序
261262
}
262263

@@ -310,7 +311,7 @@ public static int[] bitMapSort(int[] un_sort_list) {
310311
* @param <T>
311312
* @return
312313
*/
313-
public static <T extends Comparable<T>> T minInRotate(T[] arr) {
314+
public static <T extends Comparable<? super T>> T minInRotate(T[] arr) {
314315
Preconditions.checkNotNull(arr);
315316
if (arr.length == 0) {
316317
return null;
@@ -336,13 +337,13 @@ public static <T extends Comparable<T>> T minInRotate(T[] arr) {
336337
return arr[mid];
337338
}
338339

339-
public static <T> T[] group(T[] arr, Function<T, Integer> func) {
340+
public static <T> T[] group(T[] arr, Function<? super T, ? extends Integer> func) {
340341
Preconditions.checkNotNull(arr);
341342
Preconditions.checkNotNull(func);
342343
TreeMap<Integer, HashSet<T>> static_map = new TreeMap<>();
343344
for (T ele : arr) {
344-
Preconditions.checkNotNull(ele);
345-
int group_num = func.apply(ele);
345+
Integer group_num = func.apply(ele);
346+
Preconditions.checkNotNull(group_num);
346347
HashSet<T> set = static_map.get(group_num);
347348
if (set == null) {
348349
set = new HashSet<>();
@@ -452,7 +453,7 @@ private static <T> boolean checkMoreThanHalf(T[] arr, T most_ele) {
452453
* @param <T>
453454
* @return
454455
*/
455-
public static <T extends Comparable<T>> int countEle(T[] arr, T ele) {
456+
public static <T extends Comparable<? super T>> int countEle(T[] arr, T ele) {
456457
Preconditions.checkNotNull(arr);
457458
Preconditions.checkNotNull(ele);
458459
int start = getFirstEle(arr, ele);
@@ -468,7 +469,7 @@ public static <T extends Comparable<T>> int countEle(T[] arr, T ele) {
468469
* @param <T>
469470
* @return
470471
*/
471-
public static <T extends Comparable<T>> int getFirstEle(T[] arr, T ele) {
472+
public static <T extends Comparable<? super T>> int getFirstEle(T[] arr, T ele) {
472473
Preconditions.checkNotNull(arr);
473474
Preconditions.checkNotNull(ele);
474475
int start = 0;
@@ -499,7 +500,7 @@ public static <T extends Comparable<T>> int getFirstEle(T[] arr, T ele) {
499500
* @param <T>
500501
* @return
501502
*/
502-
public static <T extends Comparable<T>> int getLastEle(T[] arr, T ele) {
503+
public static <T extends Comparable<? super T>> int getLastEle(T[] arr, T ele) {
503504
Preconditions.checkNotNull(arr);
504505
Preconditions.checkNotNull(ele);
505506
int start = 0;

‎src/main/java/ssj/algorithm/Collection.java‎

Lines changed: 4 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -14,7 +14,7 @@
1414
public interface Collection<T> extends Iterable<T>, Cloneable {
1515
public void add(T ele);
1616

17-
public default <R> Collection<R> map(Function<T, R> func) {
17+
public default <R> Collection<R> map(Function<? super T, ? extends R> func) {
1818
Preconditions.checkNotNull(func);
1919
Collection<R> new_collection = newWithCapacity(size());
2020
for (T ele : this) {
@@ -23,7 +23,7 @@ public default <R> Collection<R> map(Function<T, R> func) {
2323
return new_collection;
2424
}
2525

26-
public default Collection<T> filter(Predicate<T> is_func) {
26+
public default Collection<T> filter(Predicate<? super T> is_func) {
2727
Preconditions.checkNotNull(is_func);
2828
Collection<T> new_collection = this.newWithZero();
2929
for (T ele : this) {
@@ -34,7 +34,7 @@ public default Collection<T> filter(Predicate<T> is_func) {
3434
return new_collection;
3535
}
3636

37-
public default <R> R reduce(BiFunction<T, R, R> func, R start) {
37+
public default <R> R reduce(BiFunction<? super T, ? super R, ? extends R> func, R start) {
3838
Preconditions.checkNotNull(func);
3939
Preconditions.checkNotNull(start);
4040
R new_start = start;
@@ -85,7 +85,7 @@ public default Vector<T> toVector() {
8585
return result;
8686
}
8787

88-
public default Vector<T> sort(Comparator<T> comparator) {
88+
public default Vector<T> sort(Comparator<? super T> comparator) {
8989
return toVector().sortThis(comparator);
9090
}
9191
}

‎src/main/java/ssj/algorithm/Graph.java‎

Lines changed: 6 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -15,19 +15,19 @@ public interface Graph<T> {
1515

1616
Iterator<T> nodes();
1717

18-
void dfs(Consumer<T> func);
18+
void dfs(Consumer<? super T> func);
1919

20-
<R> Vector<R> dfs(Function<T, R> func);
20+
<R> Vector<R> dfs(Function<? super T, ? extends R> func);
2121

22-
void bfs(Consumer<T> func);
22+
void bfs(Consumer<? super T> func);
2323

24-
<R> Vector<R> bfs(Function<T, R> func);
24+
<R> Vector<R> bfs(Function<? super T, ? extends R> func);
2525

2626
Vector<T> next(T ele);
2727

28-
void topologicalSort(Consumer<T> func);
28+
void topologicalSort(Consumer<? super T> func);
2929

30-
<R> Vector<R> topologicalSort(Function<T, R> func);
30+
<R> Vector<R> topologicalSort(Function<? super T, ? extends R> func);
3131

3232
int size();
3333

‎src/main/java/ssj/algorithm/List.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -52,7 +52,7 @@ public default T getReverse(int index) {
5252
return get(normal_index);
5353
}
5454

55-
List<T> partition(T par_ele, Comparator<T> comparator);
55+
List<T> partition(T par_ele, Comparator<? super T> comparator);
5656

5757
public default Set<T> chainEle() {
5858
HashSet<T> result = new HashSet<>();

‎src/main/java/ssj/algorithm/SearchTree.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -7,7 +7,7 @@
77
/**
88
* Created by shenshijun on 15/2/5.
99
*/
10-
public interface SearchTree<T extends Comparable<T>> extends Iterable<T> {
10+
public interface SearchTree<T extends Comparable<? super T>> extends Iterable<T> {
1111
void add(T ele);
1212

1313
default void addAll(Iterable<? extends T> iter) {

‎src/main/java/ssj/algorithm/Stack.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -20,7 +20,7 @@ public default boolean isEmpty() {
2020

2121
T head();
2222

23-
public default Stack<T> sortStack(Comparator<T> comparator) {
23+
public default Stack<T> sortStack(Comparator<? super T> comparator) {
2424
LinkedStack<T> result = new LinkedStack<>();
2525
while (!isEmpty()) {
2626
T cur_ele = pop();

‎src/main/java/ssj/algorithm/collections/AVLTree.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -12,7 +12,7 @@
1212
/**
1313
* Created by shenshijun on 15/2/5.
1414
*/
15-
public class AVLTree<T extends Comparable<T>> implements SearchTree<T> {
15+
public class AVLTree<T extends Comparable<? super T>> implements SearchTree<T> {
1616
private Node _head;
1717
private int _size;
1818

‎src/main/java/ssj/algorithm/collections/BTree.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -7,7 +7,7 @@
77
/**
88
* Created by shenshijun on 15/2/5.
99
*/
10-
public class BTree<T extends Comparable<T>> implements SearchTree<T> {
10+
public class BTree<T extends Comparable<? super T>> implements SearchTree<T> {
1111
//TODO 完成B树
1212
@Override
1313
public void add(T ele) {

‎src/main/java/ssj/algorithm/collections/ExtensiveStack.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -3,7 +3,7 @@
33
/**
44
* Created by shenshijun on 15/2/4.
55
*/
6-
public class ExtensiveStack<T extends Comparable<T>> extends LinkedStack<T> {
6+
public class ExtensiveStack<T extends Comparable<? super T>> extends LinkedStack<T> {
77
private LinkedStack<T> _min_stack;
88
private LinkedStack<T> _max_stack;
99

‎src/main/java/ssj/algorithm/collections/LinkedList.java‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -103,7 +103,7 @@ public void remove(int index) {
103103
}
104104

105105
@Override
106-
public List<T> partition(T par_ele, Comparator<T> comparator) {
106+
public List<T> partition(T par_ele, Comparator<? super T> comparator) {
107107
Preconditions.checkNotNull(par_ele);
108108
Preconditions.checkNotNull(comparator);
109109
Node less_node = _head.getNext();

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