在线编程-排序打印关键字

Author: xbox1994

MD/在线编程-排序打印关键字.md

@@ -0,0 +1,57 @@
+[根据输入的若干个关键字，在一个日志文件中按出现的次数排序打印输入的关键字](https://blog.csdn.net/Abysscarry/article/details/80891128)
+
+```java
+package Other.interview;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Scanner;
+import java.util.stream.Collectors;
+
+public class LogKeywords {
+    public static void main(String[] args) throws IOException {
+        File logFile = new File("/Users/tianyiwang/Downloads/JavaTest/resource/sys_info.log");
+        BufferedReader logFileReader = new BufferedReader(new FileReader(logFile));
+        System.out.println("请输入关键字：（以空格为间隔，并且关键词不能包含`符号）");
+        Scanner scanner = new Scanner(System.in);
+        String input = scanner.nextLine();
+        String[] keywords = input.split(" ");
+
+        Map<String, Integer> keywordToCountMap = new HashMap<>();
+
+        String line;
+        while ((line = logFileReader.readLine()) != null) {
+            for (String keyword : keywords) {
+                String[] split = line.split(keyword);
+                System.out.println(Arrays.toString(split));
+                int count = split.length - 1;
+                // 如果有关键字在一行字符串的最后，那么split方法将少返回一个数组
+                if (line.endsWith(keyword)) {
+                    count++;
+                }
+                if (keywordToCountMap.containsKey(keyword)) {
+                    keywordToCountMap.put(keyword, keywordToCountMap.get(keyword) + count);
+                } else {
+                    keywordToCountMap.put(keyword, count);
+                }
+            }
+        }
+
+        if (!keywordToCountMap.isEmpty()) {
+            System.out.println(keywordToCountMap
+                    .entrySet()
+                    .stream()
+                    .sorted(Map.Entry.comparingByValue())
+                    .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue)));
+        } else {
+            System.out.println("无匹配");
+        }
+    }
+}
+
+```

README.md

@@ -39,11 +39,12 @@ PS：除开知识点，一定要准备好以下内容：
 * [连续子数组最大和](https://github.com/xbox1994/2018-Java-Interview/blob/master/MD/在线编程-连续子数组最大和.md)
 * [快速排序](https://github.com/xbox1994/2018-Java-Interview/blob/master/MD/在线编程-快速排序.md)
 * [交替打印奇偶数](https://github.com/xbox1994/2018-Java-Interview/blob/master/MD/在线编程-交替打印奇偶数.md)
+* [排序打印关键字](https://github.com/xbox1994/2018-Java-Interview/blob/master/MD/在线编程-排序打印关键字.md)
 ### Linux
 * [Linux命令](https://github.com/xbox1994/2018-Java-Interview/blob/master/MD/Linux.md)
 ### 项目举例
 * [秒杀架构](https://github.com/xbox1994/2018-Java-Interview/blob/master/MD/秒杀架构.md)
 * [搜索引擎](https://github.com/xbox1994/2018-Java-Interview/blob/master/MD/搜索引擎.md)
-## 其他面试问题
+### 其他面试问题
 * [从按下回车开始，到浏览器呈现出网页之间的发生了什么](http://www.wangtianyi.top/blog/2017/10/22/cong-urlkai-shi-,ding-wei-shi-jie/)
 * [问题排查](https://github.com/xbox1994/2018-Java-Interview/blob/master/MD/问题排查.md)