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improve：更新代码排版

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sjsdfg 2019-12-15 20:04:50 +08:00
parent 814f2bcca0
commit 580c686cbf
1 changed files with 26 additions and 26 deletions
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52
docs/notes/45. 明智审慎地使用Stream.md
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@ -25,8 +25,8 @@ public class Anagrams {
try (Scanner s = new Scanner(dictionary)) { try (Scanner s = new Scanner(dictionary)) {
while (s.hasNext()) { while (s.hasNext()) {
String word = s.next(); String word = s.next();
groups.computeIfAbsent(alphabetize(word), groups.computeIfAbsent(alphabetize(word),
(unused) -> new TreeSet<>()).add(word); (unused) -> new TreeSet<>()).add(word);
} }
} }
@ -50,19 +50,19 @@ public class Anagrams {
```java ```java
// Overuse of streams - don't do this! // Overuse of streams - don't do this!
public class Anagrams { public class Anagrams {
public static void main(String[] args) throws IOException { public static void main(String[] args) throws IOException {
Path dictionary = Paths.get(args[0]); Path dictionary = Paths.get(args[0]);
int minGroupSize = Integer.parseInt(args[1]); int minGroupSize = Integer.parseInt(args[1]);
try (Stream<String> words = Files.lines(dictionary)) { try (Stream<String> words = Files.lines(dictionary)) {
words.collect( words.collect(
groupingBy(word -> word.chars().sorted() groupingBy(word -> word.chars().sorted()
.collect(StringBuilder::new, .collect(StringBuilder::new,
(sb, c) -> sb.append((char) c), (sb, c) -> sb.append((char) c),
StringBuilder::append).toString())) StringBuilder::append).toString()))
.values().stream() .values().stream()
.filter(group -> group.size() >= minGroupSize) .filter(group -> group.size() >= minGroupSize)
.map(group -> group.size() + ": " + group) .map(group -> group.size() + ": " + group)
.forEach(System.out::println); .forEach(System.out::println);
} }
} }
} }
@ -76,18 +76,18 @@ public class Anagrams {
// Tasteful use of streams enhances clarity and conciseness // Tasteful use of streams enhances clarity and conciseness
public class Anagrams { public class Anagrams {
public static void main(String[] args) throws IOException { public static void main(String[] args) throws IOException {
Path dictionary = Paths.get(args[0]); Path dictionary = Paths.get(args[0]);
int minGroupSize = Integer.parseInt(args[1]); int minGroupSize = Integer.parseInt(args[1]);
try (Stream<String> words = Files.lines(dictionary)) { try (Stream<String> words = Files.lines(dictionary)) {
words.collect(groupingBy(word -> alphabetize(word))) words.collect(groupingBy(word -> alphabetize(word)))
.values().stream() .values().stream()
.filter(group -> group.size() >= minGroupSize) .filter(group -> group.size() >= minGroupSize)
.forEach(g -> System.out.println(g.size() + ": " + g)); .forEach(g -> System.out.println(g.size() + ": " + g));
} }
} }
// alphabetize method is the same as in original version // alphabetize method is the same as in original version
} }
``` ```