我将如何打印出每行的第一个单词？

Question

我有一个文本文件，内容如下：

1. Bananas that are not green
2. Pudding that is not vanilla
3. Soda that is not Pepsi
4. Bread that is not stale

我只是想让它打印出每行的第一个单词 不包括数字！

它应该打印为：

Bananas
Pudding    
Soda    
Bread

这是我的代码：

public static void main(String[] args) {
    BufferedReader reader = null;
    ArrayList <String> myFileLines = new ArrayList <String>();

    try {
        String sCurrentLine;
        reader = new BufferedReader(new 
                FileReader("/Users/FakeUsername/Desktop/GroceryList.txt"));
        while ((sCurrentLine = reader.readLine()) != null) {
            System.out.println(sCurrentLine);               
        }
    } catch (IOException e) {
        e.printStackTrace();
        System.out.print(e.getMessage());
    } finally {
        try {
            if (reader != null)reader.close();
        } catch (IOException ex) {
            System.out.println(ex.getMessage());
            ex.printStackTrace();
        }
    }
}

Answer 1

请尝试以下代码-:

outerWhileLoop: 
while ((sCurrentLine = reader.readLine()) != null) {
     //System.out.println(sCurrentLine);
     StringTokenizer st = new StringTokenizer(sCurrentLine," .");
     int cnt = 0;
     while (st.hasMoreTokens()){
        String temp = st.nextToken();
        cnt++;
        if (cnt == 2){
           System.out.println(temp);
           continue outerWhileLoop;  
        }
    }
}

Answer 2

使用String的split函数。它 returns 根据我们要与字符串拆分的字符的字符串数组。在你的情况下，它就像下面这样。

 String sCurrentLine = new String();
 reader = new BufferedReader(new 
                FileReader("/Users/FakeUsername/Desktop/GroceryList.txt"));
 while ((sCurrentLine = reader.readLine() != null) {
    String words[] = sCurrentLine.split(" ");
    System.out.println(words[0]+" "+words[1]);
 }

Answer 3

Java 8+ 你可以使用BufferedReader的lines()方法很容易地做到这一点：

String filename = "Your filename";
reader = new BufferedReader(new FileReader(fileName));
reader.lines()
      .map(line -> line.split("\s+")[1])
      .forEach(System.out::println);

输出：

Bananas
Pudding
Soda
Bread

这将创建 BufferedReader 中所有行的 Stream，在空白处拆分每一行，然后获取第二个标记并打印它

我将如何打印出每行的第一个单词？

How would I print out the first word of each line?

java

string

arraylist

bufferedreader