如何在這個程序中首字母大寫

Question

我寫了大部分內容。 我只是無法弄清楚如何大寫每行的第一個字母。 問題是：

編寫一個程序，檢查文本文件中的幾個格式和標點符號問題。 程序要求輸入文件和輸出文件的名稱。 然后它將輸入文件中的所有文本復制到輸出文件，但是有以下兩個更改（1）任何兩個或多個空白字符的字符串被一個空格替換; （2）所有句子都以大寫字母開頭。 第一個句子之后的所有句子都在句點，問號或感嘆號之后開始，后面跟着一個或多個空白字符。

我寫了大部分代碼。 我只需要幫助每個句子的第一個字母大寫。 這是我的代碼：

import java.io.*;
import java.util.Scanner;


public class TextFileProcessor
{
public static void textFile()
{
    Scanner keyboard = new Scanner(System.in);

    String inputSent;
    String oldText;
    String newText;


    System.out.print("Enter the name of the file that you want to test: ");
    oldText = keyboard.next();

    System.out.print("Enter the name of your output file:");
    newText = keyboard.next();
    System.out.println("\n");

    try
    {
        BufferedReader inputStream = new BufferedReader(new FileReader(oldText));
        PrintWriter outputStream = new PrintWriter(new FileOutputStream(newText));
        inputSent = inputStream.readLine();

        inputSent = inputSent.replaceAll("\\s+", " ").trim();
        inputSent = inputSent.substring(0,1).toUpperCase() + inputSent.substring(1);

        inputSent = inputSent.replace("?", "?\n").replace("!", "!\n").replace(".", ".\n");
        //Find a way to make the first letter capitalized

        while(inputSent != null)
        {
            outputStream.println(inputSent);
            System.out.println(inputSent);
            inputSent = inputStream.readLine();
        }

        inputStream.close();
        outputStream.close();
    }

    catch(FileNotFoundException e)
    {
        System.out.println("File" + oldText + " could not be located.");
    }

    catch(IOException e)
    {
        System.out.println("There was an error in file" + oldText);
    }
}
}

---

import java.util.Scanner;
import java.io.*;


public class TextFileProcessorDemo
{
public static void main(String[] args)
{
    String inputName;
    String result;
    String sentence;


    Scanner keyboard = new Scanner(System.in);


    System.out.print("Enter the name of your input file: ");
    inputName = keyboard.nextLine();
    File input = new File(inputName);

    PrintWriter outputStream = null;

    try
    {
        outputStream = new PrintWriter(input);
    }

    catch(FileNotFoundException e)
    {
        System.out.println("There was an error opening the file. Goodbye!" + input);
        System.exit(0);
    }

    System.out.println("Enter a line of text:");
    sentence = keyboard.nextLine();

    outputStream.println(sentence);
    outputStream.close();

    System.out.println("This line was written to:" + " " + input);
    System.out.println("\n");

}
}

Answer 1

最簡單的方法是使用Apache commons-langs的WordUtil 。

您應該使用capitalise方法和分隔符作為參數。

Answer 2

由於你的代碼已經包含inputSent = inputSent.substring(0,1).toUpperCase() + inputSent.substring(1); 我假設inputSent可以包含多個句子，或者可能只是用句子的一部分來表示文件的一行。

因此，我建議你先將整個文件讀入一個字符串（如果它不是太大）然后在該字符串上使用split()將其分解為單個句子，將第一個字符大寫並再次連接它們。

例：

String[] sentences = fileContent.split("(?<=[?!.])\\s*");
StringBuilder result = new StringBuilder();
for( String sentence : sentences) {
  //append the first character as upper case
  result.append( Character.toUpperCase( sentence.charAt(0) ) );
  //add the rest of the sentence
  result.append( sentence.substring(1) );
  //add a newline
  result.append("\n");
}

//I'd not replace the input, but to be consistent with your code
fileContent = result.toString();

Answer 3

您可以嘗試以下正則表達式：

(\S)([^.!?]*[.!?]( |$))

• 碼：

   public static void main(String[] args) { String inputSent = "hi! how are you? fine, thanks."; inputSent = inputSent.replaceAll("\\\\s+", " ").trim(); Matcher m = Pattern.compile("(\\\\S)([^.!?]*[.!?]( |$))").matcher(inputSent); StringBuffer sb = new StringBuffer(); while (m.find()) { m.appendReplacement(sb, m.group(1).toUpperCase() + m.group(2) + "\\n"); } m.appendTail(sb); System.out.println(sb); } 

  在線觀看演示 。

• 輸出：

   Hi! How are you? Fine, thanks. 

Answer 4

在ASCII表中，大小寫只是整數，彼此相距32個位置......

嘗試這樣的事情：

String inputSent = .... //where ever it does come from...
System.out.println(inputSent.replace(inputSent.charAt(0), (char) (inputSent.charAt(0) - 32)));

或者使用像WordUtils這樣的某種APACHE庫。

Answer 5

我會將textFile()更改為以下內容：

public static void textFile()
{
    Scanner keyboard = new Scanner(System.in);

    String inputSent;
    String oldText;
    String newText;


    System.out.print("Enter the name of the file that you want to test: ");
    oldText = keyboard.next();

    System.out.print("Enter the name of your output file:");
    newText = keyboard.next();
    System.out.println("\n");

    try
    {
        BufferedReader inputStream = new BufferedReader(new FileReader(oldText));
        PrintWriter outputStream = new PrintWriter(new FileOutputStream(newText));
        while ((inputSent = inputStream.readLine()) != null) {
            char[] chars = inputSent.toCharArray();
            chars[0] = Character.toUpperCase(chars[0]);
            inputSent = new String(chars);

            inputSent = inputSent.replaceAll("\\s+", " ").trim();
            inputSent = inputSent.substring(0,1).toUpperCase() + inputSent.substring(1);

            inputSent = inputSent.replace("?", "?\n").replace("!", "!\n").replace(".", ".\n");
            System.out.println("-> " + inputSent);
            outputStream.println(inputSent);

        }
        inputStream.close();
        outputStream.close();
    }

    catch(FileNotFoundException e)
    {
        System.out.println("File" + oldText + " could not be located.");
    }

    catch(IOException e)
    {
        System.out.println("There was an error in file" + oldText);
    }
}

1. 這將逐行讀取文本文件。
2. 上面的第一個字符
3. 在while循環中執行此操作

原始textFile（）的問題在於它只在它讀取的第一行應用大寫的第一個字符，空格等。