java - 从另一个方法获取变量

Question

//Import packages
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.JTextArea;
import javax.swing.JScrollPane;

import java.io.IOException;
import java.io.PrintWriter;
import java.io.File;

//Main class
public class gui1{
//Declare variables
static JFrame frame1;
static Container pane;
static JScrollPane Scroll;
static JButton Submit;
static JLabel Client, DateServiced, NameofPC, Manufacturer, CPUBIT, CPUTYPE, SerialNumber, ProductNumber, Harddriveplug, TypeofHD, MotherboardModel, TypeofRam, ModelofHardDrive, SpeedofHarddrive, AmountofRam, ThingsDone, CustomerStatements, OtherComments, Technician;
static JTextField TClient, TDateServiced, TNameofPC, TManufacturer, TCPUBIT, TCPUTYPE, TSerialNumber, TProductNumber, THarddriveplug, TTypeofHD, TMotherboardModel, TTypeofRam, TModelofHardDrive, TSpeedofHarddrive, TAmountofRam, TTechnician;
static Insets insets;
static JTextArea TThingsDone, TCustomerStatements, TOtherComments;
public static void main (String args[]){
    //Set Look and Feel
    try {UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());}
    catch (ClassNotFoundException e) {}
    catch (InstantiationException e) {}
    catch (IllegalAccessException e) {}
    catch (UnsupportedLookAndFeelException e) {}

    //Create the frame
    frame1 = new JFrame ("Trouble Ticket");
    frame1.setSize (800,800);
    pane = frame1.getContentPane();
    frame1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE );
    insets = pane.getInsets();
    pane.setLayout (null);

    //Create controls
    Submit = new JButton ("Submit");
    Client = new JLabel ("Client");
    DateServiced = new JLabel ("Date Serviced");
    NameofPC = new JLabel ("Designated Name of PC");
    Manufacturer = new JLabel ("Manufacturer of Entire PC Such as HP or Dell");
    CPUBIT = new JLabel ("64 or 32 Bit CPU");
    CPUTYPE = new JLabel ("Model of CPU");
    SerialNumber = new JLabel ("Serial Number on Case");
    ProductNumber = new JLabel ("Product Number on Case");
    Harddriveplug = new JLabel ("Type Of Harddrive connector");
    TypeofHD = new JLabel ("HDD or SDD");
    MotherboardModel = new JLabel ("Moderboard Model");
    TypeofRam = new JLabel ("Type of Ram");
    AmountofRam = new JLabel ("Amount of Ram");
    ModelofHardDrive = new JLabel ("Model of Hard Drive");
    SpeedofHarddrive = new JLabel ("Speed of Hard Drive");
    CustomerStatements = new JLabel ("Customer Statements");
    ThingsDone = new JLabel ("What was done to the Machine");
    OtherComments = new JLabel ("Comments");
    Technician = new JLabel ("Working Technician");

    TClient = new JTextField (25);
    TDateServiced = new JTextField (8);
    TNameofPC = new JTextField (25);
    TManufacturer = new JTextField (25);
    TCPUBIT = new JTextField (2);
    TSerialNumber = new JTextField (20);
    TProductNumber = new JTextField (22);
    THarddriveplug = new JTextField (4);
    TTypeofHD = new JTextField (3);
    TModelofHardDrive = new JTextField (25);
    TSpeedofHarddrive = new JTextField (10);
    TCustomerStatements = new JTextArea (5,20);
    TThingsDone = new JTextArea (5,20);
    TOtherComments = new JTextArea (5,20);
    TTechnician = new JTextField (25);
    TCustomerStatements.setLineWrap(true);
    TOtherComments.setLineWrap(true);
    TThingsDone.setLineWrap(true);

    //Add all components to panel
    pane.add (Client);
    pane.add (DateServiced);
    pane.add (NameofPC);
    pane.add (Manufacturer);
    pane.add (CPUBIT);
    pane.add (SerialNumber);
    pane.add (ProductNumber);
    pane.add (Harddriveplug);
    pane.add (TypeofHD);
    pane.add (ModelofHardDrive);
    pane.add (SpeedofHarddrive);
    pane.add (ThingsDone);
    pane.add (CustomerStatements);
    pane.add (OtherComments);
    pane.add (Technician);
    pane.add (TClient);
    pane.add (TDateServiced); 
    pane.add (TNameofPC); 
    pane.add (TManufacturer);
    pane.add (TCPUBIT);
    pane.add (TSerialNumber);
    pane.add (TProductNumber);
    pane.add (THarddriveplug);
    pane.add (TTypeofHD);
    pane.add (TModelofHardDrive);
    pane.add (TSpeedofHarddrive);
    pane.add (TThingsDone);
    pane.add (TCustomerStatements);
    pane.add (TOtherComments);
    pane.add (TTechnician);

    pane.add(Submit);

    //Place all components
    Client.setBounds (insets.left + 5, insets.top + 5, Client.getPreferredSize().width, Client.getPreferredSize().height);
    TClient.setBounds (Client.getX() + Client.getPreferredSize().width + 35, insets.top + 5, TClient.getPreferredSize().width, TClient.getPreferredSize().height);
    DateServiced.setBounds (Client.getX(), insets.top + 40, DateServiced.getPreferredSize().width, DateServiced.getPreferredSize().height);
    TDateServiced.setBounds (Client.getX() + DateServiced.getPreferredSize().width + 35, insets.top + 40, TDateServiced.getPreferredSize().width, TDateServiced.getPreferredSize().height);
    Manufacturer.setBounds (Client.getX(), DateServiced.getY() + 35, Manufacturer.getPreferredSize().width, Manufacturer.getPreferredSize().height);
    TManufacturer.setBounds (Client.getX() + Manufacturer.getPreferredSize().width + 35, DateServiced.getY() + 35, TManufacturer.getPreferredSize().width, TManufacturer.getPreferredSize().height);
    CPUBIT.setBounds (Client.getX(), Manufacturer.getY() + 35, CPUBIT.getPreferredSize().width, CPUBIT.getPreferredSize().height);
    TCPUBIT.setBounds (Client.getX() + CPUBIT.getY() + 35, Manufacturer.getY() + 35, TCPUBIT.getPreferredSize().width, TCPUBIT.getPreferredSize().height);
    SerialNumber.setBounds (Client.getX(), CPUBIT.getY() + 35, SerialNumber.getPreferredSize().width, SerialNumber.getPreferredSize().height);
    TSerialNumber.setBounds (Client.getX() + SerialNumber.getPreferredSize().width + 35, CPUBIT.getY() + 35, TSerialNumber.getPreferredSize().width, TSerialNumber.getPreferredSize().height);      
    ProductNumber.setBounds (Client.getX(), SerialNumber.getY() + 35, ProductNumber.getPreferredSize().width, ProductNumber.getPreferredSize().height);
    TProductNumber.setBounds (Client.getX() + ProductNumber.getPreferredSize().width + 35, SerialNumber.getY() + 35, TProductNumber.getPreferredSize().width, TProductNumber.getPreferredSize().height);
    Harddriveplug.setBounds (Client.getX(), ProductNumber.getY() + 35, Harddriveplug.getPreferredSize().width, Harddriveplug.getPreferredSize().height);
    THarddriveplug.setBounds (Client.getX() + ProductNumber.getPreferredSize().width + 35, ProductNumber.getY() + 35, THarddriveplug.getPreferredSize().width, THarddriveplug.getPreferredSize().height);
    TypeofHD.setBounds (Client.getX(), Harddriveplug.getY() + 35, TypeofHD.getPreferredSize().width, TypeofHD.getPreferredSize().height);
    TTypeofHD.setBounds (Client.getX() + Harddriveplug.getPreferredSize().width + 35, Harddriveplug.getY() + 35, TTypeofHD.getPreferredSize().width, TTypeofHD.getPreferredSize().height);
    ModelofHardDrive.setBounds (Client.getX(), TypeofHD.getY() + 35, ModelofHardDrive.getPreferredSize().width, ModelofHardDrive.getPreferredSize().height);
    TModelofHardDrive.setBounds (Client.getX() + ModelofHardDrive.getPreferredSize().width + 35, TypeofHD.getY() + 35, TModelofHardDrive.getPreferredSize().width, TModelofHardDrive.getPreferredSize().height);
    SpeedofHarddrive.setBounds (Client.getX(), ModelofHardDrive.getY() +35, SpeedofHarddrive.getPreferredSize().width, SpeedofHarddrive.getPreferredSize().height);
    TSpeedofHarddrive.setBounds (Client.getX() + SpeedofHarddrive.getPreferredSize().width + 35, ModelofHardDrive.getY() +35, TSpeedofHarddrive.getPreferredSize().width, TSpeedofHarddrive.getPreferredSize().height);
    Technician.setBounds (Client.getX(), SpeedofHarddrive.getY() +35, Technician.getPreferredSize().width, Technician.getPreferredSize().height);

    TTechnician.setBounds (Client.getX() + Technician.getPreferredSize().width + 35, TSpeedofHarddrive.getY() +35, TTechnician.getPreferredSize().width, TTechnician.getPreferredSize().height);        

    ThingsDone.setBounds (Client.getX(), Technician.getY() +35, ThingsDone.getPreferredSize().width, ThingsDone.getPreferredSize().height);

    TThingsDone.setBounds (Client.getX(), ThingsDone.getY() +35, TThingsDone.getPreferredSize().width, TThingsDone.getPreferredSize().height);  

    CustomerStatements.setBounds (Client.getX(), TThingsDone.getY() + TThingsDone.getPreferredSize().height +35, CustomerStatements.getPreferredSize().width, CustomerStatements.getPreferredSize().height);

    TCustomerStatements.setBounds (Client.getX(),CustomerStatements.getY() +CustomerStatements.getPreferredSize().height +35, TCustomerStatements.getPreferredSize().width, TCustomerStatements.getPreferredSize().height);

    OtherComments.setBounds (Client.getX() + TCustomerStatements.getPreferredSize().width + 35, CustomerStatements.getY(), OtherComments.getPreferredSize().width, OtherComments.getPreferredSize().height);

    TOtherComments.setBounds (Client.getX() + TCustomerStatements.getPreferredSize().width + 35, TCustomerStatements.getY(), TOtherComments.getPreferredSize().width, TOtherComments.getPreferredSize().height);
    Submit.setBounds(TClient.getX() + TClient.getPreferredSize().width + 65, Client.getY(), Submit.getPreferredSize().width, Submit.getPreferredSize().height);
    //Set frame visible
    frame1.setVisible (true);

    //Button's action
    Submit.addActionListener(new Submitaction()); //Register action
}

public static class Submitaction implements ActionListener{
    public void actionPerformed (ActionEvent e){
        String Clientname = TClient.getText();
        String DateofService = TDateServiced.getText();
        String Nameofpc = TNameofPC.getText();
        String manufacturer = TManufacturer.getText();
        String CPUBit = TCPUBIT.getText();
        String Serialnumber = TSerialNumber.getText();
        String Productnumber = TProductNumber.getText();
        String HardDriveplug = THarddriveplug.getText();
        String Typeofhd = TTypeofHD.getText();
        String ModelofHarddrive = TModelofHardDrive.getText();
        String SpeedofHardDrive = TSpeedofHarddrive.getText();
        String WhatDidtheCustomerSay = TCustomerStatements.getText();
        String WorkDone = TThingsDone.getText();
        String TechniciansComments = TOtherComments.getText();
        String TechnicianWorking = TTechnician.getText();
    }
    public static void Save(String arg[]) throws IOException
    {
        File save = new File("/home/bekk/Outline.txt");
        PrintWriter out = new PrintWriter("home/bekk/Outline.txt"); 
        PrintWriter.println(Clientname);

            }
    }
}

这是我的全部代码

我想讨论的部分如下

public static class Submit implements ActionListener{
    public void actionPerformed (ActionEvent e){
        String Clientname = TClient.getText();
        String DateofService = TDateServiced.getText();
        String Nameofpc = TNameofPC.getText();
        String manufacturer = TManufacturer.getText();
        String CPUBit = TCPUBIT.getText();
        String Serialnumber = TSerialNumber.getText();
        String Productnumber = TProductNumber.getText();
        String HardDriveplug = THarddriveplug.getText();
        String Typeofhd = TTypeofHD.getText();
        String ModelofHarddrive = TModelofHardDrive.getText();
        String SpeedofHardDrive = TSpeedofHarddrive.getText();
        String WhatDidtheCustomerSay = TCustomerStatements.getText();
        String WorkDone = TThingsDone.getText();
        String TechniciansComments = TOtherComments.getText();
        String TechnicianWorking = TTechnician.getText();
    }
    public static void Save(String arg[]) throws IOException
    {
        File save = new File("/home/bekk/Outline.txt");
        PrintWriter out = new PrintWriter("home/bekk/Outline.txt"); 
        PrintWriter.println(Clientname);

            }
    }
}

我正在尝试从文本字段/文本区域获取字符串，然后将它们保存到文件中。我将将输入保存到 .txt 文件的代码部分放在其自己的方法中，因为它会抛出异常，表示不存在文件。我如何访问在方法提交中获取值的变量，然后让它在方法保存中将该值保存到文本文件中。
或者找到一种替代方法来实现我上面提到的总体目标。

Answer 1

您有几个选择。

你可以

如果发生错误，只需处理...

public void actionPerformed (ActionEvent e){
    //...

    File save = new File("/home/bekk/Outline.txt");
    PrintWriter out = null;
    try {
        out = new PrintWriter(save); 
        out.println(Clientname);
        //...
    } catch (IOException exp) {
        JOptionPane.showMessageDialog(null, "Failed to save file", "Error", JOptionPane.ERROR_MESSAGE);
    } finally {
        try {
            out.close();
        } catch (Exception exp) {
        }
    }
}

这是“好的”，但是您确实倾向于将许多可能可重用的代码封装在一个方法中......

你可以

创建一个保存方法并将要保存的值传递给它...

public void actionPerformed (ActionEvent e){
    //...

    File save = new File("/home/bekk/Outline.txt");
    try {
        save(save, Clientname,
            DateofService,
            Nameofpc,
            manufacturer,
            CPUBit,
            Serialnumber,
            Productnumber,
            HardDriveplug,
            Typeofhd,
            ModelofHarddrive,
            SpeedofHardDrive,
            WhatDidtheCustomerSay,
            WorkDone,
            TechniciansComments,
            TechnicianWorking);
    } catch (IOException exp) {
        JOptionPane.showMessageDialog(null, "Failed to save file", "Error", JOptionPane.ERROR_MESSAGE);
    }
}

public void save(File save, String... values) throws IOException {
    PrintWriter out = null;
    try {
        out = new PrintWriter(save); 
        for (String value : values) {
            out.println(value);
        }
    } finally {
        try {
            out.close();
        } catch (Exception exp) {
        }
    }
}

这仍然需要您自己处理IOException，但提供了一段可重用的代码，将来可以扩展/覆盖该代码以提供其他可能性。

你可以

将您尝试保存的属性封装到对象中并使用类似Java Architecture for XML Binding (JAXB)的内容管理它...

但是...

这些都无法修复“它抛出异常，表示不存在文件”，因为该文件根本无法写入。

最可能的原因是文件路径不存在，而不是文件不存在。系统无法在您尝试创建新文件的位置创建新文件。

你可以尝试类似...

File save = new File("/home/bekk");
if (!save.exists()) {
    JOptionPane.showMessageDialog(this, save + " does not exist", "Error", JOptionPane.ERROR_MESSAGE);    
} else if (!save.isDirectory()) {
    JOptionPane.showMessageDialog(this, save + " is not a directory", "Error", JOptionPane.ERROR_MESSAGE);    
}

检查它。

虽然有许多可能的解决方案，但就您的情况而言，最好使用...

File save = new File(System.getProperty("user.home"));

这将为您提供用户的主目录...

如果需要，您还可以使用File#mkdirs创建所需的目录结构...

File save = new File("/home/bekk");
if (save.exists() || save.mkdirs()) {
    save = new File(save + File.separator + "Outline.txt");
    //...
}