Question

如何在java中编写一个读取文本文件并查找每个字符出现次数的方法？然后在您阅读它们时将项目存储到arraylist中。

Answer 1

首先打开.txt文件并阅读其内容然后创建一个Hashmap并迭代字符以进行计数

    BufferedReader br = new BufferedReader(new FileReader(fileName));
    HashMap<Character,Integer> hm;    
    StringBuilder sb = new StringBuilder();
    String line = br.readLine();

    while (line != null) {
         //iterate over the string and increment  
         //hashmap.get("character") by one
         line = br.readLine();
    }

Answer 2

您可以使用FileReader打开文件，然后使用存储每个角色出现的int[]。

BufferedReader br = new BufferedReader(new FileReader(fileName));
int[] characters = new int[65535];
StringBuilder sb = new StringBuilder();
int i = 0;

while ((i = br.read()) >= 0)
{
     characters[i]++;
}

如何在java中编写一个读取文本文件并查找每个字符出现次数的方法？

2 个答案: