如何设置图像的相对路径？

Question

How do I set a relative path for images?

public class Currency2 extends JFrame implements ActionListener{
    private JButton USA_btn, INDIA_btn, DUBAI_btn, AUSTRALIA_btn, ITALY_btn, MALAYSIA_btn, SINGAPORE_btn, ENGLAND_btn, SAUDI_btn, QATAR_btn;
    public Currency2 cr2;
    ImagePanel panel_secondframe;
    Border thickBorder;
    public Currency2(){
        super("Currency Converter");
        this.InitializeComponents();
    }
    @Override
    public void actionPerformed(ActionEvent e) {
        String Object = e.getActionCommand();
        if(Object.equals("USA")){
            Currency_USA cus = new Currency_USA(this);
            cus.setVisible(true);
            this.setVisible(false);
        }
        else if(Object.equals("INDIA")){
            Currency_INDIA cin = new Currency_INDIA(this);
            cin.setVisible(true);
            this.setVisible(false);
        }
        else if(Object.equals("DUBAI")){
            Currency_DUBAI cdu = new Currency_DUBAI(this);
            cdu.setVisible(true);
            this.setVisible(false);
        }
        else if(Object.equals("ITALY")){
           Currency_ITALY cit = new Currency_ITALY(this);
           cit.setVisible(true);
           this.setVisible(false);
        }
        else if(Object.equals("ENGLAND")){
           Currency_ENGLAND cei = new Currency_ENGLAND(this);
           cei.setVisible(true);
           this.setVisible(false);
        }
        else if(Object.equals("AUSTRALIA")){
            Currency_AUSTRALIA cau = new Currency_AUSTRALIA(this);
            cau.setVisible(true);
            this.setVisible(false);
        }
        else if(Object.equals("MALAYSIA")){
           Currency_MALAYSIA cma = new Currency_MALAYSIA(this);
           cma.setVisible(true);
           this.setVisible(false);
        }
        else if(Object.equals("SINGAPORE")){
           Currency_SINGAPORE csi = new Currency_SINGAPORE(this);
           csi.setVisible(true);
           this.setVisible(false);
        }
        else if(Object.equals("SAUDI")){
           Currency_SAUDI cssi = new Currency_SAUDI(this);
           cssi.setVisible(true);
           this.setVisible(false);
        }
        else if(Object.equals("QATAR")){
           Currency_QATAR cqa = new Currency_QATAR(this);
           cqa.setVisible(true);
           this.setVisible(false);
        }
    }
private void InitializeComponents() {
    this.panel_secondframe = new ImagePanel(new ImageIcon("E:\\programing \\JAVA\\new netbean pro\\currency\\src\\newpackage\\image of currency converter\\secondframe.png").getImage());
    this.getContentPane().add(panel_secondframe);
    this.pack();

    this.thickBorder = new LineBorder(Color.black);

    this.USA_btn = new JButton("USA");
    this.USA_btn.setBounds(136, 35, 89, 23);
    this.USA_btn.addActionListener(this);
    this.USA_btn.setBorder(thickBorder);
    this.panel_secondframe.add(USA_btn);

    this.INDIA_btn = new JButton("INDIA");
    this.INDIA_btn.setBounds(136, 65, 89, 23);
    this.INDIA_btn.addActionListener(this);
    this.INDIA_btn.setBorder(thickBorder);
    this.panel_secondframe.add(INDIA_btn);

    this.DUBAI_btn = new JButton("DUBAI");
    this.DUBAI_btn.setBounds(136, 95, 89, 23);
    this.DUBAI_btn.addActionListener(this);
    this.DUBAI_btn.setBorder(thickBorder);
    this.panel_secondframe.add(DUBAI_btn);

    this.ITALY_btn = new JButton("ITALY");
    this.ITALY_btn.setBounds(136, 125, 89, 23);
    this.ITALY_btn.addActionListener(this);
    this.ITALY_btn.setBorder(thickBorder);
    this.panel_secondframe.add(ITALY_btn);

    this.SAUDI_btn = new JButton("SAUDI");
    this.SAUDI_btn.setBounds(136, 155, 89, 23);
    this.SAUDI_btn.addActionListener(this);
    this.SAUDI_btn.setBorder(thickBorder);
    this.panel_secondframe.add(SAUDI_btn);

    this.QATAR_btn = new JButton("QATAR");
    this.QATAR_btn.setBounds(136, 185, 89, 23);
    this.QATAR_btn.addActionListener(this);
    this.QATAR_btn.setBorder(thickBorder);
    this.panel_secondframe.add(QATAR_btn);

    this.ENGLAND_btn = new JButton("ENGLAND");
    this.ENGLAND_btn.setBounds(129, 215, 102, 23);
    this.ENGLAND_btn.addActionListener(this);
    this.ENGLAND_btn.setBorder(thickBorder);
    this.panel_secondframe.add(ENGLAND_btn);

    this.AUSTRALIA_btn = new JButton("AUSTRALIA");
    this.AUSTRALIA_btn.setBounds(129, 245, 102, 23);
    this.AUSTRALIA_btn.addActionListener(this);
    this.AUSTRALIA_btn.setBorder(thickBorder);
    this.panel_secondframe.add(AUSTRALIA_btn);

    this.MALAYSIA_btn = new JButton("MALAYSIA");
    this.MALAYSIA_btn.setBounds(129, 275, 102, 23);
    this.MALAYSIA_btn.addActionListener(this);
    this.MALAYSIA_btn.setBorder(thickBorder);
    this.panel_secondframe.add(MALAYSIA_btn);

    this.SINGAPORE_btn = new JButton("SINGAPORE");
    this.SINGAPORE_btn.setBounds(129, 305, 102, 23);
    this.SINGAPORE_btn.addActionListener(this);
    this.SINGAPORE_btn.setBorder(thickBorder);
    this.panel_secondframe.add(SINGAPORE_btn);

    this.add(this.panel_secondframe);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}

Answer 1

要设置相对路径，请替换为

this.panel_secondframe = new ImagePanel(new ImageIcon(".\\src\\newpackage\\image of currency converter\\secondframe.png").getImage());

Answer 2

Java class Class has a static method getResourceAsStream(path) which is able to load common resources from the package structure of the application itself. This is rather useful and common to use in your situation.

Suppose you have your images inside com.yourpackage.icons (so com/yourpackage/icons as your real path, then you can use

ImageIcon icon = new ImageIcon(ImageIO.read(this.getClass().getResourceAsStream("/com/yourpackage/icons/imagename.png")));