java - 包含更多类(class)的地址簿程序

Question

嗨。我正在寻求帮助，将我的代码拆分为单独的类，以便它运行得更好。

这是一个简单的地址簿程序，允许用户执行多种操作:

1. 添加联系人

2. 搜索

3. 删除

4. 显示全部

5. 退出

我是 java 新手，所以我需要所有可以获得的帮助!

我的代码:

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;

public class AddressBookOperations
{


    public static void main(String[] args) throws IOException
    {
        String s = null;
        String s2 = null;
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));

        // Console in = System.console();

        while (s2 != "5"){
        System.out.println(" Welcome, Please enter an option: \n"
                             + "---------------------------------\n"
                        + " 1- Add contact\n 2- search contact\n 3- delete contact\n 4- display all contacts\n 5- exit\n");
        s2 = in.readLine();

        if (s2.equals("5"))
        {
            System.exit(0);
        }

        else
        {
            s = s2;
        }

        if (s != null)
        {
            String dataLine;
            String data;
            if (s.equals("1")) {
                System.out.println("Enter Name: ");
                dataLine = in.readLine();
                data = dataLine;
                in = new BufferedReader(new InputStreamReader(System.in));
                System.out.println("Enter LastName: ");
                dataLine = in.readLine();
                data = data + "--" + dataLine;
                System.out.println("Enter Address: ");
                dataLine = in.readLine();
                data = data + "--" + dataLine;
                System.out.println("Enter PhoneNumber: ");
                dataLine = in.readLine();
                data = data + "--" + dataLine;
                writeToFile("AddressBookData.dat", data, true, true);
            }
            else if (s.equals("2")) // Search contact
            {
                System.out.println("Enter Name 0r PhoneNumber: ");
                dataLine = in.readLine();
                String result = readFromFile("C:/AddressBookData.dat", dataLine);
                System.out.println("Search Results\n" + result);
            }
            else if (s.equals("3")) // Delete contact
            {
                System.out.println("Enter Name: ");
                dataLine = in.readLine();
                data = dataLine;
                System.out.println("PhoneNumber: ");
                dataLine = in.readLine();
                data = data + "--" + dataLine;
                deleteFromFile("AddressBookData.dat", data);
            }
            else if (s.equals("4")) // Display all contacts
            {
                String result = readFromFile("AddressBookData.dat", null);
                System.out.println("All contacts\n" + result);



                }
            }
        }
    }

    private static void deleteFromFile(String string, String dataLine) 
    {
        String data = readFromFile(string, null);
        data = data.replaceAll(dataLine, "");
        writeToFile(string, data, false, false);
    }

    public static boolean writeToFile(String fileName, String dataLine,
            boolean isAppendMode, boolean isNewLine) {
        if (isNewLine) {
            dataLine = "\n" + dataLine;
        }

        try {
            File outFile = new File(fileName);
            DataOutputStream dos;
            if (isAppendMode) {
                dos = new DataOutputStream(new FileOutputStream(fileName, true));
            } else {
                dos = new DataOutputStream(new FileOutputStream(outFile));
            }

            dos.writeBytes(dataLine);
            dos.close();
        } catch (FileNotFoundException ex) {
            return (false);
        } catch (IOException ex) {
            return (false);
        }
        return (true);

    }


     // Reads data from a given file

    public static String readFromFile(String fileName, String dataLine2)
    {
        String DataLine = "";
        String fileData = "";
        try
        {
            File inFile = new File(fileName);
            BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(inFile)));

            if (dataLine2 != null)
            {
                while ((DataLine = br.readLine()) != null)
                {
                    if (DataLine.contains(dataLine2))
                    {
                        fileData = DataLine;
                    }
                }
            }

            else
            {
                while ((DataLine = br.readLine()) != null)
                {
                    fileData = fileData + "\n" + DataLine;
                    //System.out.println(DataLine);
                }
            }
            br.close();
        }

        catch (FileNotFoundException ex)
        {
            return (null);
        } catch (IOException ex)
        {
            return (null);
        }
        return (fileData);

    }

    public static boolean isFileExists(String fileName)
    {
        File file = new File(fileName);
        return file.exists();
    }
}

Answer 1

您之前问过几乎相同的问题，我最终为您提供了整个问题的所有代码。

这个问题在这里:Address book that reads and write from a data file

从那里，您所要做的就是将 Contact 放入名为 Contact.java 的文件中，并使类定义读取 public class Contact {。然后对 ContactDriver 执行相同的操作。

另一方面，您现在提出了三个与同一个项目相关的问题，基本上让我们为您编写整个项目。我对编写代码并没有真正的问题，因为这对我来说是一个很好的实践，但我确实对您表现出不努力并反复提出问题以使我们为您编写整个应用程序感到不满。