Java BufferedReader 行为怪异

Question

我一生都无法理解为什么 bufferedreader 没有读取我文件中的下一行。它一直返回一个空字符串。我以正确的格式将阅读器置于 while 循环中。我的文本文件不包含任何特殊字符。它只包含数字和一些由空格分隔的字符串。没看懂。

//Read from file method
public void readFile(File x) throws IOException{
    File rFile = x;
    String fileLine;
    Transaction holder;
    int Type;
    //This will destroy the current account to add in the new one
    //Main.$acct.destroyTrans();

    try {
        // FileReader reads text files in the default encoding.
        FileReader fileReader = new FileReader(rFile);

        // Always wrap FileReader in BufferedReader.
        BufferedReader bufferedReader = new BufferedReader(fileReader);
        //Gathering initial information about account
        Main.$acct.setName(bufferedReader.readLine());
        Main.$acct.setBalance(Double.parseDouble(bufferedReader.readLine()));
        Main.$acct.setTransCount(Integer.parseInt(bufferedReader.readLine()));
        Main.$acct.setSC(Double.parseDouble(bufferedReader.readLine()));
        //Adding the objects
        while((fileLine = bufferedReader.readLine()) != null) {
            //Tokenize the String to extract information
            StringTokenizer st = new StringTokenizer(fileLine," ");          
            //Go through each token and put it into an arrayList
            ArrayList<String> list = new ArrayList();
            while(st.hasMoreTokens()) {
                list.add(st.nextToken());
            }
            //Grab each piece of data
            Type = Integer.parseInt(list.get(0));
            //Route the proper objects to their proper places
            switch(Type){
                case 1:
                {
                holder = new Check(Integer.parseInt(list.get(1)), Type,  Double.parseDouble(list.get(3)), Integer.parseInt(list.get(2)));
                Main.$acct.addNewTrans(holder);
                break;
                }
                case 2:
                {
                holder = new Deposit(Integer.parseInt(list.get(1)), Type, Double.parseDouble(list.get(5)), Double.parseDouble(list.get(3)),
                Double.parseDouble(list.get(4)));
                Main.$acct.addNewTrans(holder);
                break;
                }
                case 3:
                {
                holder = new Transaction(Integer.parseInt(list.get(1)), Type, Double.parseDouble(list.get(4)));
                Main.$acct.addNewTrans(holder);
                break;
                }
                default:
                {}  
            }
            //End of switch
        }
        //End of while loop

        bufferedReader.close();
    }  
    //End of Try
    //Exception handling portion
    catch(FileNotFoundException ex) {
        System.out.println(
            "Unable to open file '" +
            rFile.getName() + "'");               
    }
    catch(IOException ex) {
        System.out.println(
            "Error reading file '"
            + rFile.getName() + "'");                 
        // Or we could just do this:
        // ex.printStackTrace();
    }
}

示例文件：

比利

500

4

5

1 0 1 100

3 1 伺服。钟。 0.15

2 2 存款 100 100 200

Answer 1

只要输入文件格式和编码是标准的，您的代码就可以正常运行。 确保您的输入文件没有多余的换行符（或文件末尾的额外换行符）； 我用 ANSI 编码的文件测试了你的代码，它按预期工作。

修复您的异常处理以处理一般情况 - 它将帮助您调试错误。

即在方法的末尾做这样的事情：

} catch(Exception e) {
    // Throw the exception here, or print it to the console...
    e.printStackTrace();
}

祝你好运！