Question

我正在编写一个与＆＃34; Transactions.txt＆＃34;交互的程序。文件的格式如下。

TransactionNumber,ItemName,Quantity,Purchase/HireDate,ReturnDate

其内容为：

T01,Jumper,5,10/03/2015,14/03/2015
T02,Tuxedo,1,21/04/2015,23/05/2015
T03,Jacket,2,02/07/2015,09/07/2015
T04,Hat,3,12/09/2015,19/09/2015
T05,Shoes,4,09/11/2015,20/11/2015

该计划的目标是获取开始日期并检查文件中的所有日期，以查看开始日期是否在任何日期之前，如果是，它将添加项目名称，它的数量和它的购买/雇用日期以及它返回要打印的字符串的日期。例如，如果我输入10/03/2015作为开始日期，则应打印所有内容，但只打印出第1,2和4行，我不知道问题出在哪里。

我还尝试添加一段将在结束日期到达的代码，并检查文件中的任何日期是否在结束日期之后，如果是，则输出将被打印然后它应该完成执行main（不是exit（0）因为我与其他类交互。所以如果我然后输入10/03/2015作为开始日期和15/03/2015作为结束日期，只有行将打印1的内容。

我已经尝试解决这个问题几个小时了，我无法找到问题所在，任何帮助都会非常感激。

import java.io.*;
import java.util.*;
import java.text.*;
public static File transactionsFile = new File("Transactions.txt");
public class Transaction
{
    public static void main() throws IOException
    {
        try
        {
            String details = "";
            Date tempDate;
            SimpleDateFormat SDF = new SimpleDateFormat("dd/mm/yyyy");
            System.out.print("Enter in a start date (dd/mm/yyyy): ");
            String sDate = userInput.nextLine();
            Date startDate = SDF.parse(sDate);
            System.out.print("Enter in an end date (dd/mm/yyyy): ");
            String eDate = userInput.nextLine();
            Date endDate = SDF.parse(eDate);
            List<String[]> contents = new ArrayList<>();
            Scanner searchTransactionsFile = new Scanner(transactionsFile);
            System.out.println("\n---------Summary of Transactions---------");

            while(searchTransactionsFile.hasNextLine())
            {
                String[] current = searchTransactionsFile.nextLine().split(",");
                contents.add(current);
            }

            for(String[] elements: contents)
            {
                tempDate = SDF.parse(elements[3]);
                if(tempDate.after(startDate) || tempDate.equals(startDate))
                    details += "\nItem Name:\t\t" + elements[1] + "\nQuantity:\t\t" + elements[2] + "\nHire/Purchase Date:\t" + elements[3] + "\nReturn Date:\t\t" + elements[4] + "\n";
            }
            System.out.print(details);
            searchTransactionsFile.close();
        }
        catch(Exception e)
        {
            System.out.println("Invalid date entered. Please enter a valid date in the format dd/mm/yyyy");
        }
    }
}

Answer 1

把这一行

public static File transactionsFile = new File("Transactions.txt");

内部类定义。您必须定义userInput变量。像这样

Scanner userInput = new Scanner(System.in);

此外，您必须将日期格式修改为：

SimpleDateFormat SDF = new SimpleDateFormat("dd/M/yyyy");

因为mm表示分钟而M表示月份;

Answer 2

你的条件错了。它没有考虑结束日期。我已经改变逻辑来考虑startDate和endDate。看看吧。

if（tempDate.after（startDate）＆amp;＆amp; tempDate.before（endDate））

import java.io.*;
import java.util.*;
import java.text.*;

public class Transaction {
    public static File transactionsFile = new File("Transactions.txt");

    public static void main(String args[]) throws IOException {

        try {

            String details = "";
            Date tempDate;
            SimpleDateFormat SDF = new SimpleDateFormat("dd/mm/yyyy");
            System.out.print("Enter in a start date (dd/mm/yyyy): ");
            Scanner userInput = new Scanner(System.in);
            String sDate = userInput.nextLine();
            Date startDate = SDF.parse(sDate);
            System.out.print("Enter in an end date (dd/mm/yyyy): ");
            String eDate = userInput.nextLine();
            Date endDate = SDF.parse(eDate);
            List<String[]> contents = new ArrayList<>();
            Scanner searchTransactionsFile = new Scanner(transactionsFile);
            System.out.println("\n---------Summary of Transactions---------");

            while (searchTransactionsFile.hasNextLine()) {
                String[] current = searchTransactionsFile.nextLine().split(",");
                contents.add(current);
            }

            for (String[] elements : contents) {
                tempDate = SDF.parse(elements[3]);
                if (tempDate.after(startDate) && tempDate.before(endDate))
                    details += "\nItem Name:\t\t" + elements[1]
                            + "\nQuantity:\t\t" + elements[2]
                            + "\nHire/Purchase Date:\t" + elements[3]
                            + "\nReturn Date:\t\t" + elements[4] + "\n";
            }
            System.out.print(details);
            searchTransactionsFile.close();
        } catch (Exception e) {
            System.out
                    .println("Invalid date entered. Please enter a valid date in the format dd/mm/yyyy");
        }
    }
}

输出：

D:\Study\Examples\src>java Transaction
Enter in a start date (dd/mm/yyyy): 10/03/2015
Enter in an end date (dd/mm/yyyy): 15/03/2015

---------Summary of Transactions---------

Item Name:              Hat
Quantity:               3
Hire/Purchase Date:     12/09/2015
Return Date:            19/09/2015

将输入与.txt文件中的日期进行比较的问题

2 个答案: