解析统计文本文件中的字符数、单词数、行数。

用android 编程解析统计文本文件中的字符数、单词数、行数（作业）
主要代码
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private void analysis() {
String str = " ";
int words = 0;
int chars = 0;
int lines = 0;
int spaces = 0;
int marks = 0;
int character = 0;

String filename = et_name.getText().toString();
FileInputStream fis = null;
BufferedReader br = null;
try {
    if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
        File file = new File(Environment.getExternalStorageDirectory().getCanonicalPath() + "/" + filename + ".txt");
    if (file.exists()) {
        fis = new FileInputStream(file);
        br = new BufferedReader(new InputStreamReader(fis));
    while ((str = br.readLine()) != null) {
    char[] b = str.toCharArray();
    for (int i = 0; i < str.length(); i++) {
    if (b[i] == ' ') {
        spaces++;
                    } else if (b[i] == ',' || b[i] == '.') {
                        marks++;

                    }
                }
                words += str.split("[ \.,]").length;
                chars += str.length();
                lines++;
            }
            character = chars - (spaces + marks);
            fis.close();

            tv_read.setText("单词数：" + words + ",字符数：" + chars + ",行数：" + lines + ",字母数：" + character + ",空格数：" + spaces + "，标点符号数：" + marks);
        } else {
            Toast.makeText(this, "不存在该文件", Toast.LENGTH_SHORT).show();
        }
    }
} catch (Exception e) {
    e.printStackTrace();
}

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