我已经获得了Java代码来创建一个记事本项目而且我无法运行它。似乎代码会生成警告。我正在使用带有Java的NetBeans IDE 8.01。当我尝试运行程序时,我在一个框中得到以下内容:
firstprojectnote.FirstProjectNote wasn´t found in FirstProjectNote project. select main class <no main class found>
我认为它没有Main的类别?谢谢你的帮助。
package firstprojectnote;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.Scanner;
import java.io.*;
public class FirstProjectNote extends JFrame implements ActionListener {
public class notepad {
public void main(String args[]) {
app.setVisible(true);
}
}
private TextArea textArea = new TextArea("", 0, 0, TextArea.SCROLLBARS_VERTICAL_ONLY);
private MenuBar menuBar = new MenuBar();
private Menu file = new Menu();
private MenuItem openFile = new MenuItem();
private MenuItem saveFile = new MenuItem();
private MenuItem close = new MenuItem();
public FirstProjectNote() {
this.setSize(500, 300);
this.setTitle("Java Notepad Tutorial");
setDefaultCloseOperation(EXIT_ON_CLOSE);
this.textArea.setFont(new Font("Century Gothic", Font.BOLD, 12));
this.getContentPane().setLayout(new BorderLayout());
this.getContentPane().add(textArea);
this.setMenuBar(this.menuBar);
this.menuBar.add(this.file);
this.file.setLabel("File");
this.openFile.setLabel("Open");
this.openFile.addActionListener(this);
this.openFile.setShortcut(new MenuShortcut(KeyEvent.VK_O, false));
this.file.add(this.openFile);
this.saveFile.setLabel("Save");
this.saveFile.addActionListener(this);
this.saveFile.setShortcut(new MenuShortcut(KeyEvent.VK_S, false));
this.file.add(this.saveFile);
this.close.setLabel("Close");
this.close.setShortcut(new MenuShortcut(KeyEvent.VK_F4, false));
this.close.addActionListener(this);
this.file.add(this.close);
}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == this.close)
this.dispose();
else if (e.getSource() == this.openFile) {
JFileChooser open = new JFileChooser();
int option = open.showOpenDialog(this);
if (option == JFileChooser.APPROVE_OPTION) {
this.textArea.setText("");
try {
Scanner scan = new Scanner(new
FileReader(open.getSelectedFile().getPath()));
while (scan.hasNext())
this.textArea.append(scan.nextLine() + "\n");
} catch (Exception ex) {
System.out.println(ex.getMessage());
}
}
} else if (e.getSource() == this.saveFile) {
JFileChooser save = new JFileChooser();
int option = save.showSaveDialog(this);
if (option == JFileChooser.APPROVE_OPTION) {
try {
BufferedWriter out = new BufferedWriter(new
FileWriter(save.getSelectedFile().getPath()));
out.write(this.textArea.getText());
out.close();
} catch (Exception ex) {
System.out.println(ex.getMessage());
}
}
}
}
}
答案 0 :(得分:1)
我确定你的主要方法需要是静态的。
public static void main(String args[]) {
app.setVisible(true);
}