java实现wc函数功能(附完整源码)

以下是Java实现wc函数功能的完整源码：

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

public class WordCount {

    public static int countLines(String fileName) throws IOException {
        BufferedReader reader = new BufferedReader(new FileReader(fileName));
        int lines = 0;

        while (reader.readLine() != null) {
            lines++;
        }

        reader.close();
        return lines;
    }

    public static int countWords(String fileName) throws IOException {
        BufferedReader reader = new BufferedReader(new FileReader(fileName));
        int words = 0;

        String line = reader.readLine();
        while (line != null) {
            String[] parts = line.split("\\s+");
            words += parts.length;
            line = reader.readLine();
        }

        reader.close();
        return words;
    }

    public static int countCharacters(String fileName) throws IOException {
        BufferedReader reader = new BufferedReader(new FileReader(fileName));
        int characters = 0;

        int c = reader.read();
        while (c != -1) {
            characters++;
            c = reader.read();
        }

        reader.close();
        return characters;
    }

    public static void main(String[] args) {
        String fileName = "test.txt";

        try {
            int lines = countLines(fileName);
            int words = countWords(fileName);
            int characters = countCharacters(fileName);

            System.out.println("Lines: " + lines);
            System.out.println("Words: " + words);
            System.out.println("Characters: " + characters);
        } catch (IOException e) {
            System.out.println("Error: " + e.getMessage());
        }
    }
}

这个程序可以接受一个文件名作为输入，并计算文件中的行数、单词数和字符数。它通过使用BufferedReader读取文件内容，并通过调用Java的String类中的split()方法来计算单词数。最后，它将结果输出到控制台。