为什么JFrame背景图片无法正常工作？

Question

I am trying to Show a background Image but it will not work, i have tried multiple things it comes back with this error ever time. Every time it says Duplicate field i don't know what that means I am a beginner in java

Here is the Error

Exception in thread "main" java.lang.ClassFormatError: Duplicate field        name&signature in class file search/text/file/SearchTextFile$1
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at search.text.file.SearchTextFile.<init>(SearchTextFile.java:46)
at search.text.file.SearchTextFile.main(SearchTextFile.java:42)
Java Result: 1

And this try block causing background error :

    try {            
    BufferedImage img = ImageIO.read(new File("bible.jpg"));
    } catch(IOException e ) {

    }

Thank You

Java Code: package search.text.file;

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Image;
import java.awt.Insets;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import javax.imageio.ImageIO;
import javax.swing.DefaultListCellRenderer;
import javax.swing.DefaultListModel;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class SearchTextFile {

public static void main(String[] args) {
    new SearchTextFile();
}

public SearchTextFile() {
    EventQueue.invokeLater(new Runnable() {
        @Override
        public void run() {
            try {
                UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
            } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
            }


            JFrame frame = new JFrame("Bible Search");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setLayout(new BorderLayout());
            frame.add(new TestPane());
            frame.pack();
            frame.setLocationRelativeTo(null);
            frame.setVisible(true);
        }
try {            
BufferedImage img = ImageIO.read(new File("bible.jpg"));
} catch(IOException e ) {
}
});


}

public class TestPane extends JPanel {

    private JTextField findText;
    private JButton search;
    private DefaultListModel<String> model;
    private JList list;

    private String searchPhrase;

    public TestPane() {
        setLayout(new BorderLayout());
        JPanel searchPane = new JPanel(new GridBagLayout());
        GridBagConstraints gbc = new GridBagConstraints();
        gbc.gridx = 0;
        gbc.gridy = 0;
        gbc.insets = new Insets(2, 2, 2, 2);
        searchPane.add(new JLabel("Find: "), gbc);
        gbc.gridx++;
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.weightx = 1;
        findText = new JTextField(20);
        searchPane.add(findText, gbc);

        gbc.gridx++;
        gbc.fill = GridBagConstraints.NONE;
        gbc.weightx = 0;
        search = new JButton("Search");
        searchPane.add(search, gbc);

        add(searchPane, BorderLayout.NORTH);

        model = new DefaultListModel<>();
        list = new JList(model);
        list.setCellRenderer(new HighlightListCellRenderer());
        add(new JScrollPane(list));

        ActionHandler handler = new ActionHandler();

        search.addActionListener(handler);
        findText.addActionListener(handler);

        try (BufferedReader reader = new BufferedReader(new InputStreamReader(getClass().getResourceAsStream("bible.txt")))) {

            String text = null;
            while ((text = reader.readLine()) != null) {
                model.addElement(text);
            }

        } catch (IOException exp) {

            exp.printStackTrace();

        }
    }

    public class ActionHandler implements ActionListener {

        @Override
        public void actionPerformed(ActionEvent e) {
            searchPhrase = findText.getText();
            if (searchPhrase != null && searchPhrase.trim().length() == 0) {
                searchPhrase = null;
            }
            list.repaint();
//              model.removeAllElements();
////                    BufferedReader reader = null;
//
//              String searchText = findText.getText();
//              try (BufferedReader reader = new BufferedReader(new     FileReader(new File("bible.txt")))) {
//
//                  String text = null;
//                  while ((text = reader.readLine()) != null) {
//
//                      if (text.contains(searchText)) {
//
//                          model.addElement(text);
//
//                      }
//
//                  }
//
//              } catch (IOException exp) {
//
//                  exp.printStackTrace();
//                  JOptionPane.showMessageDialog(TestPane.this, "Something Went     Wrong", "Error", JOptionPane.ERROR_MESSAGE);
//
//              }
        }
    }

    public class HighlightListCellRenderer extends DefaultListCellRenderer {

        public final String WITH_DELIMITER = "((?<=%1$s)|(?=%1$s))";

        @Override
        public Component getListCellRendererComponent(JList<?> list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
            if (value instanceof String && searchPhrase != null) {
                String text = (String) value;
                if (text.contains(searchPhrase)) {
                    text = text.replace(" ", "&nbsp;");
                    value = "<html>" + text.replace(searchPhrase, "<span STYLE='background-color: #ffff00'>" + searchPhrase + "</span>") + "</html>";
                }
            }
            return super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus); //To change body of generated methods, choose Tools | Templates.
        }

    }
}
}

Answer 1

Your try block:

try {            
BufferedImage img = ImageIO.read(new File("bible.jpg"));
} catch(IOException e ) {
}
});

is outside of any method or constructor, and this is not allowed. I suggest that you

1. move it to within a constructor or method.
2. Don't ignore the exceptions as you're doing as this is very dangerous coding. At least print out the exception's stack trace.

Also, why are you reading in an image but then doing nothing with it?

eg

public class SearchTextFile2 {

    private static void createAndShowGui() {
        BufferedImage img = null;
        try {
            // better to get as a resource and not as a File
            img = ImageIO.read(new File("bible.jpg"));
        } catch (IOException e) {
            e.printStackTrace();
        }

        JFrame frame = new JFrame("SearchTextFile2");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().add(new TestPane(img)); // pass image into TestPane
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGui();
            }
        });
    }

    // make TestPane a static inner class
    // have TestPane display image within its paintComponent method
    public static class TestPane extends JPanel {
        private JTextField findText;
        private JButton search;
        private DefaultListModel<String> model;
        private JList list;
        private BufferedImage img;
        private String searchPhrase;

        public TestPane(BufferedImage img) {
            setLayout(new BorderLayout());
            this.img = img;
            // etc.....
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            if (img != null) {
                g.drawImage(img, 0, 0, this);
            }
        }
        // .....

Answer 2

looks like all classes you placed in one file might be that would be messed in your case please check java docs for error

Java Virtual Machine attempts to read a class file and determines that the file is malformed or otherwise cannot be interpreted as a class file

http://docs.oracle.com/javase/7/docs/api/java/lang/ClassFormatError.html