java - 使用 Java 查找和替换文本文件中的单词

Question

我正在尝试使用 Java 查找和替换文本文件中的某些单词。我的代码在一定程度上有效，但我得到的输出是错误的。我需要用用户输入替换文本文件中一行的多个单词。但是，当我运行我的代码时，该行会为我尝试替换的每个单词复制一次。

例如，如果我想替换以下 3 个单词:

python ycsb phase db -s -P /home/james/YCSB/workloads/workloada -p 
db.url=db://IP:port -p db.database=name

我最终得到了该行的 3 个副本，每个副本都替换了一个不同的词。而不是替换所有 3 个所需单词的 1 行。下面提供了代码，在此先感谢。

public static void main(String[] args) {

    System.out.print("Phase: ");
    Scanner sp = new Scanner(System.in);
    String p = sp.nextLine();
    
    System.out.print("Database: ");
    Scanner sd = new Scanner(System.in);
    String d = sd.nextLine();
    
    System.out.print("IP address: ");
    Scanner sip = new Scanner(System.in);
    int ip = sip.nextInt();
     
    try {
        File file = new File("C://users//James//Desktop//newcommand.txt");
        BufferedReader reader = new BufferedReader(new FileReader(file));
        String line = "", oldtext = "";
        while((line = reader.readLine()) != null) {
            oldtext += line + "\r\n";
        }
        reader.close();
       
        String phase  = oldtext.replaceAll("phase", "" + p);
        String database = oldtext.replaceAll("db", "" + d);
        String ips = oldtext.replaceAll("IP", "" + ip);
        
        FileWriter writer = new FileWriter("C://users//James//Desktop//newcommand.txt");
        writer.write(phase + ips + database);
        writer.close();
    } catch (IOException e) {
        // handle e
    }
}

Answer 1

如果我很了解情况，也许问题是你正在替换相同的字符串，并存储在不同的 var 中，

试试看:

  public static void main(String[] args) {
        System.out.print("Phase: ");
        Scanner sp = new Scanner(System.in);
        String p;
        p = sp.nextLine();

        System.out.print("Database: ");
        Scanner sd = new Scanner(System.in);
        String d;
        d = sd.nextLine();

        System.out.print("IP address: ");
        Scanner sip = new Scanner(System.in);
        int ip = sip.nextInt();

        {
         try
             {
             File file = new File("C://users//James//Desktop//newcommand.txt");
             BufferedReader reader = new BufferedReader(new FileReader(file));
             String line = "", oldtext = "";
             while((line = reader.readLine()) != null)
                 {
                 oldtext += line + "\r\n";
             }
             reader.close();

             String replacedtext  = oldtext.replaceAll("phase", "" + p);
             replacedtext = replacedtext.replaceAll("db", "" + d);
             replacedtext = replacedtext.replaceAll("IP", "" + ip);

             FileWriter writer = new FileWriter("C://users//James//Desktop//newcommand.txt");
             writer.write(replacedtext);


             writer.close();

         }
         catch (IOException ioe)
             {
             ioe.printStackTrace();
         }
     }