java - 将数据从文件打印到数组

Question

我需要将此文件打印到数组，而不是屏幕。是的，我必须使用数组 - 学校项目 - 我对 java 很陌生，因此不胜感激。有任何想法吗？谢谢

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Scanner;

public class HangmanProject
{
    public static void main(String[] args) throws FileNotFoundException
    {

        String scoreKeeper;     // to keep track of score
        int guessesLeft;        // to keep track of guesses remaining
        String wordList[];    // array to store words


        Scanner keyboard = new Scanner(System.in);    // to read user's input

        System.out.println("Welcome to Hangman Project!");

        // Create a scanner to read the secret words file
        Scanner wordScan = null;

        try {
            wordScan = new Scanner(new BufferedReader(new FileReader("words.txt")));
            while (wordScan.hasNext()) {
                System.out.println(wordScan.next());
            }
        } finally {
            if (wordScan != null) {
                wordScan.close();
            }
        }
    }
}

Answer 1

尼克，你刚刚给了我们最后一 block 拼图。如果您知道要读取的行数，则可以在读取文件之前简单地定义该长度的数组

类似...

String[] wordArray = new String[10];
int index = 0;
String word = null; // word to be read from file...
// Use buffered reader to read each line...
    wordArray[index] = word;
    index++;

老实说，这个例子没有多大意义，所以我做了这两个例子

第一个使用 Alex 建议的概念，它允许您从文件中读取未知数量的行。

唯一的问题是行之间被更多的一个换行符分隔(即单词之间有一个额外的行)

public static void readUnknownWords() {

    // Reference to the words file
    File words = new File("Words.txt");
    // Use a StringBuilder to buffer the content as it's read from the file
    StringBuilder sb = new StringBuilder(128);

    BufferedReader reader = null;
    try {

        // Create the reader.  A File reader would be just as fine in this
        // example, but hay ;)
        reader = new BufferedReader(new FileReader(words));
        // The read buffer to use to read data into
        char[] buffer = new char[1024];
        int bytesRead = -1;
        // Read the file to we get to the end
        while ((bytesRead = reader.read(buffer)) != -1) {

            // Append the results to the string builder
            sb.append(buffer, 0, bytesRead);

        }

        // Split the string builder into individal words by the line break
        String[] wordArray = sb.toString().split("\n");

        System.out.println("Read " + wordArray.length + " words");

    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            reader.close();
        } catch (Exception e) {
        }
    }

}

第二个演示如何将单词读入已知长度的数组中。这可能更接近您真正想要的

public static void readKnownWords() 

    // This is just the same as the previous example, except we
    // know in advance the number of lines we will be reading    
    File words = new File("Words.txt");

    BufferedReader reader = null;
    try {

        // Create the word array of a known quantity
        // The quantity value could be defined as a constant
        // ie public static final int WORD_COUNT = 10;
        String[] wordArray = new String[10];

        reader = new BufferedReader(new FileReader(words));
        // Instead of reading to a char buffer, we are
        // going to take the easy route and read each line
        // straight into a String
        String text = null;
        // The current array index
        int index = 0;
        // Read the file till we reach the end
        // ps- my file had lots more words, so I put a limit
        // in the loop to prevent index out of bounds exceptions
        while ((text = reader.readLine()) != null && index < 10) {

            wordArray[index] = text;
            index++;

        }

        System.out.println("Read " + wordArray.length + " words");

    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            reader.close();
        } catch (Exception e) {
        }
    }

}

如果您发现其中任何一个有用，我会适本地给我一个小小的赞成票，并检查亚历克斯的答案是否正确，因为我已经适应了他的想法。

现在，如果您真的对使用哪个换行符很担心，您可以通过 System.getProperties().getProperty("line.separator") 找到系统使用的值值。