我有一个非常好的大小项目，我正在这里工作，我正在调整一个部分，现在我正在使用当我尝试运行代码时弹出的错误框。它之前正在工作，我改变的唯一是“创建承包商”。我认为错误要么在该部分，要么在底部。我正在使用Eclipse来运行代码，在运行它之后，我不仅会弹出该框，而且代码底部会显示一条消息：java.lang.NoSuchMethodError：主要异常在线程“main”中
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.io.*;
public class test extends JFrame implements ActionListener{
private JTabbedPane jtabbedPane;
private JPanel General;
private JPanel Pools;
private JPanel HotTub;
private JPanel Customers;
private JPanel Contractors;
JTextField lengthTextPool, widthTextPool, depthTextPool, volumeTextPool,
lengthTextHotTub, widthTextHotTub, depthTextHotTub, volumeTextHotTub;
JTextArea NameTextCustomers, ExistTextCustomers;
public test(){
setTitle("Volume Calculator");
setSize(300, 200);
JPanel topPanel = new JPanel();
topPanel.setLayout( new BorderLayout() );
getContentPane().add( topPanel );
createGeneral();
createPools();
createHotTub();
createCustomers();
createContractors();
jtabbedPane = new JTabbedPane();
jtabbedPane.addTab("General", General);
jtabbedPane.addTab("Pool", Pools);
jtabbedPane.addTab("Hot Tub", HotTub);
jtabbedPane.addTab("Customers", Customers);
jtabbedPane.addTab("Contractors", Contractors);
topPanel.add(jtabbedPane, BorderLayout.CENTER);
}
/* GENERAL */
public void createGeneral(){
General = new JPanel();
General.setLayout( null );
JLabel DateLabel = new JLabel("Today's Date");
DateLabel.setBounds(10, 15, 150, 20);
General.add( DateLabel );
JFormattedTextField date = new JFormattedTextField(
java.util.Calendar.getInstance().getTime());
date.setEditable(false);
date.setBounds(90,15,150,20);
General.add(date);
JButton Exit = new JButton("Exit");
Exit.setBounds(20,50,80,20);
Exit.addActionListener(this);
Exit.setBackground(Color.white);
General.add(Exit);
}
/* CREATE POOL */
public void createPools(){
Pools = new JPanel();
Pools.setLayout( null );
JLabel lengthLabelPool = new JLabel("Length of pool (ft):");
lengthLabelPool.setBounds(10, 15, 260, 20);
Pools.add( lengthLabelPool );
lengthTextPool = new JTextField();
lengthTextPool.setBounds(180, 15, 150, 20);
Pools.add( lengthTextPool );
JLabel widthLabelPool = new JLabel("Width of pool (ft):");
widthLabelPool.setBounds(10, 40, 260, 20);
Pools.add( widthLabelPool );
widthTextPool = new JTextField();
widthTextPool.setBounds(180, 40, 150, 20);
Pools.add( widthTextPool );
JLabel depthLabelPool = new JLabel("Average Depth of pool (ft):");
depthLabelPool.setBounds( 10, 65, 260, 20 );
Pools.add( depthLabelPool );
depthTextPool = new JTextField();
depthTextPool.setBounds(180, 65, 150, 20);
Pools.add( depthTextPool );
JLabel volumeLabelPool = new JLabel("The pool's volume is:(ft ^3");
volumeLabelPool.setBounds(10, 110, 260, 20);
Pools.add( volumeLabelPool );
volumeTextPool = new JTextField();
volumeTextPool.setBounds(180, 110, 150, 20);
volumeTextPool.setEditable(false);
Pools.add(volumeTextPool);
JButton calcVolumePool = new JButton("Calculate Pool Volume");
calcVolumePool.setBounds(20,250,180,20);
calcVolumePool.addActionListener(this);
calcVolumePool.setBackground(Color.white);
Pools.add(calcVolumePool);
JButton Exit = new JButton("Exit");
Exit.setBounds(220,250,80,20);
Exit.addActionListener(this);
Exit.setBackground(Color.white);
Pools.add(Exit);
}
/* CREATE HOT TUB */
public void createHotTub(){
HotTub = new JPanel();
HotTub.setLayout( null );
JLabel lengthLabel2 = new JLabel("Length of Hot Tub (ft):");
lengthLabel2.setBounds(10, 15, 260, 20);
HotTub.add( lengthLabel2 );
lengthTextHotTub = new JTextField();
lengthTextHotTub.setBounds(180, 15, 150, 20);
HotTub.add( lengthTextHotTub );
JLabel widthLabelHotTub = new JLabel("Width of Hot Tub (ft):");
widthLabelHotTub.setBounds(10, 40, 260, 20);
HotTub.add( widthLabelHotTub );
widthTextHotTub = new JTextField();
widthTextHotTub.setBounds(180, 40, 150, 20);
HotTub.add( widthTextHotTub );
JLabel depthLabelHotTub = new JLabel("Average Depth of Hot Tub (ft):");
depthLabelHotTub.setBounds( 10, 65, 260, 20 );
HotTub.add( depthLabelHotTub );
depthTextHotTub = new JTextField();
depthTextHotTub.setBounds(180, 65, 150, 20);
HotTub.add( depthTextHotTub );
JLabel volumeLabelHotTub = new JLabel("The Hot Tub's volume is:(ft ^3");
volumeLabelHotTub.setBounds(10, 110, 260, 20);
HotTub.add( volumeLabelHotTub );
volumeTextHotTub = new JTextField();
volumeTextHotTub.setBounds(180, 110, 150, 20);
volumeTextHotTub.setEditable(false);
HotTub.add(volumeTextHotTub);
JButton calcVolume = new JButton("Calculate Hot Tub Volume");
calcVolume.setBounds(20,250,180,20);
calcVolume.addActionListener(this);
calcVolume.setBackground(Color.white);
HotTub.add(calcVolume);
JButton Exit = new JButton("Exit");
Exit.setBounds(220,250,80,20);
Exit.addActionListener(this);
Exit.setBackground(Color.white);
HotTub.add(Exit);
}
/* CREATE CUSTOMERS */
public void createCustomers(){
Customers = new JPanel();
Customers.setLayout( null );
NameTextCustomers = new JTextArea();
NameTextCustomers.setBounds(10, 10, 350, 150);
NameTextCustomers.setLineWrap(true);
Customers.add(NameTextCustomers);
JButton Exit = new JButton("Exit");
Exit.setBounds(30,170,80,20);
Exit.addActionListener(this);
Exit.setBackground(Color.white);
Customers.add(Exit);
JButton AddCustomers = new JButton("Add Customer");
AddCustomers.setBounds(130,170,120,20);
AddCustomers.setBackground(Color.white);
Customers.add(AddCustomers);
JButton Refresh = new JButton("Refresh");
Refresh.setBounds(260,170,80,20);
Refresh.setBackground(Color.white);
Customers.add(Refresh);
ExistTextCustomers = new JTextArea();
ExistTextCustomers.setBounds(10, 200, 350, 60);
ExistTextCustomers.setLineWrap(true);
Customers.add(ExistTextCustomers);
}
/* CREATE CONTRACTORS */
public JPanel createContractors(){
final JTextArea contArea = new JTextArea(6, 30);
final JTextArea contMessage;
JButton addContractor = new JButton("Add Contractor");
addContractor.setMnemonic('a');
JPanel contPanel = new JPanel();
contArea.setText("Select Add Contractor to add contractor. Select Refresh to refresh this pane.");
contArea.setForeground(Color.orange);
contArea.setLineWrap(true);
contArea.setWrapStyleWord(true);
JButton contRefButton = new JButton("Refresh");
contMessage = new JTextArea(2, 30);
contMessage.setLineWrap(true);
contMessage.setWrapStyleWord(true);
addContractor.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{ // action if button is used
new Contractor("Contractor");
}// end actionPerformed()//end action performed
}); // end performed action
contPanel.add(contArea);
contPanel.add(addContractor);
contPanel.add(contRefButton);
contPanel.add(contMessage);
contRefButton.setMnemonic('R');
contRefButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
contMessage.setText("");
try
{
File contOpen = new File("contractor.txt");
FileReader contAreaIn = new FileReader(contOpen);
contArea.read(contAreaIn, contOpen.toString());
contMessage.setText("The file exists and can be read from.");
}
catch (IOException e3)
{
contMessage.setText("The file can't be read." + e3.getMessage());
}
}
});
return contPanel;
}
class Contractor extends JFrame
{
private String[] states = { "AL", "AK", "AZ", "AR", "CA", "CO", "CT", "DE",
"FL", "GA", "HI", "ID", "IL", "IN", "IA", "KS", "KY", "LA", "ME",
"MD", "MA", "MI", "MN", "MS", "MO", "MT", "NE", "NV", "NH", "NJ",
"NM", "NY", "NC", "ND", "OH", "OK", "OR", "PA", "RI", "SC", "SD",
"TN", "TX", "UT", "VT", "VA", "WA", "WV", "WI", "WY" };
private JComboBox StateList = new JComboBox(states);
private JTextField NameText = new JTextField(25);
private JTextField AddressText = new JTextField(25);
private JTextField CityText = new JTextField(25);
private JTextField ZipText = new JTextField(9);
private JTextField PhoneText = new JTextField(10);
private JTextField PopMessageText = new JTextField(30);
private static final long serialVersionUID = 1L;
private AddContButtonHandler addContHandler = new AddContButtonHandler();
public Contractor(String who)
{
popUpWindow(who);
}
public void popUpWindow(final String who) {
final JFrame popWindow;
popWindow = new JFrame(who);
popWindow.setSize(425, 350);
popWindow.setLocation(100, 100);
popWindow.setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);
Container A = new Container();
popWindow.add(A);
A.setLayout(new FlowLayout());
JPanel Name = new JPanel();
JPanel Address = new JPanel();
JPanel City = new JPanel();
JPanel SZP = new JPanel();
JPanel File = new JPanel();
JPanel Message = new JPanel();
Name.add(new JLabel(who + "Name"));
Name.add(NameText);
Address.add(new JLabel("Address"));
Address.add(AddressText);
City.add(new JLabel("City"));
City.add(CityText);
SZP.add(new JLabel("State"));
StateList.setSelectedIndex(0);
SZP.add(StateList);
SZP.add(new JLabel("Zip"));
SZP.add(ZipText);
SZP.add(new JLabel("Phone"));
SZP.add(PhoneText);
JButton addwho = new JButton("Add" + who);
addwho.setMnemonic('A');
JButton close = new JButton("Close");
close.setMnemonic('C');
JButton deleteFile = new JButton("Delete File");
deleteFile.setMnemonic('D');
File.add(addwho);
File.add(close);
File.add(deleteFile);
PopMessageText.setEditable(false);
PopMessageText.setHorizontalAlignment(JTextField.CENTER);
Message.add(PopMessageText);
A.add(Name);
A.add(Address);
A.add(City);
A.add(SZP);
A.add(File);
A.add(Message);
deleteFile.setToolTipText("Delete File");
addwho.setToolTipText("Add "+ who);
close.setToolTipText("Close");
if (who == "Contractor")
addwho.addActionListener(addContHandler); // registers listener
close.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
NameText.setText("");
AddressText.setText("");
CityText.setText("");
ZipText.setText("");
PhoneText.setText("");
PopMessageText.setText("");
popWindow.dispose();
}
});
deleteFile.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
PopMessageText.setText("");
if (who == "Contractor") {
File file = new File("Contractor.txt");
boolean contFileDeleted = file.delete();
if (contFileDeleted) {
PopMessageText
.setText("Contractor file deleted");
} else {
PopMessageText
.setText("Error deleting file");
}
}
}
});
}
class AddContButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent addContHandler) {
int StateIndex;
try {
File file = new File("Contractor.txt");
boolean success = file.createNewFile();
if (success) {
PopMessageText
.setText("Contractor.txt file created file added");
} else if (file.canWrite()) {
PopMessageText
.setText("Writing info. to Contractor.txt, file added");
} else {
PopMessageText.setText("Cannot create file: Contractor.txt");
}
try {
FileWriter fileW = new FileWriter("Contractor.txt", true);
fileW.write(NameText.getText());
fileW.write(",");
fileW.write(AddressText.getText());
fileW.write(",");
fileW.write(CityText.getText());
fileW.write(",");
StateIndex = StateList.getSelectedIndex();
fileW.write(states[StateIndex]);
fileW.write(",");
fileW.write(ZipText.getText());
fileW.write(",");
fileW.write(PhoneText.getText());
fileW.write("\r\n");
fileW.close();
PopMessageText.setText("Contractor has been added!");
FileReader fileR = new FileReader("Contractor.txt");
BufferedReader buffIn = new BufferedReader(fileR);
buffIn.readLine();
buffIn.close();
}
catch (IOException e1) {
JOptionPane.showMessageDialog(null, e1.getMessage(),
"Error", 2);
}
NameText.setText("");
AddressText.setText("");
CityText.setText("");
ZipText.setText("");
PhoneText.setText("");
} catch (IOException e1) {
}
}
}
public void actionPerformed(ActionEvent event){
JButton button = (JButton)event.getSource();
String buttonLabel = button.getText();
if ("Exit".equalsIgnoreCase(buttonLabel)){
Exit_pressed(); return;
}
if ("Calculate Pool Volume".equalsIgnoreCase(buttonLabel)){
Calculate_VolumePool(); return;
}
if ("Calculate Hot Tub Volume".equalsIgnoreCase(buttonLabel)){
Calculate_VolumeHotTub(); return;
}
}
private void Exit_pressed(){
System.exit(0);
}
private void Calculate_VolumePool(){
String lengthStringPool, widthStringPool, depthStringPool;
int lengthPool=0;
int widthPool=0;
int depthPool=0;
lengthStringPool = lengthTextPool.getText();
widthStringPool = widthTextPool.getText();
depthStringPool = depthTextPool.getText();
if (lengthStringPool.length() < 1 || widthStringPool.length() < 1 || depthStringPool.length() < 1 ){
volumeTextPool.setText("Enter All 3 Numbers"); return;
}
lengthPool = Integer.parseInt(lengthStringPool);
widthPool = Integer.parseInt(widthStringPool);
depthPool = Integer.parseInt(depthStringPool);
if (lengthPool != 0 || widthPool != 0 || depthPool != 0 ){
volumeTextPool.setText((lengthPool * widthPool * depthPool) + "");
} else{
volumeTextPool.setText("Enter All 3 Numbers"); return;
}
}
private void Calculate_VolumeHotTub(){
String lengthStringHotTub, widthStringHotTub, depthStringHotTub;
int lengthHotTub=0;
int widthHotTub=0;
int depthHotTub=0;
lengthStringHotTub = lengthTextHotTub.getText();
widthStringHotTub = widthTextHotTub.getText();
depthStringHotTub = depthTextHotTub.getText();
if (lengthStringHotTub.length() < 1 || widthStringHotTub.length() < 1 || depthStringHotTub.length() < 1 ){
volumeTextHotTub.setText("Enter All 3 Numbers"); return;
}
lengthHotTub = Integer.parseInt(lengthStringHotTub);
widthHotTub = Integer.parseInt(widthStringHotTub);
depthHotTub = Integer.parseInt(depthStringHotTub);
if (lengthHotTub != 0 || widthHotTub != 0 || depthHotTub != 0 ){
volumeTextHotTub.setText((lengthHotTub * widthHotTub * depthHotTub) + "");
} else{
volumeTextHotTub.setText("Enter All 3 Numbers"); return;
}
}
public void main(String[] args){
JFrame frame = new test();
frame.setSize(380, 350);
frame.setVisible(true);
}
}
public void actionPerformed(ActionEvent e) {
}
}
答案 0 :(得分：5)
main（）必须是静态的.......
编辑：我建议您在IDE中使用自动格式化程序修复格式。这会使主方法的错误放置更加明显。答案 1 :(得分：2)
将main方法移至class“test”（来自Contractor）并将声明更改为static。顺便说一句。关于java命名约定类名应该以大写字母
开头更改您的469行：
public void main(String[] args) // bad
要：
public static void main(String[] args) // good
答案 2 :(得分：1)
public void main(String[] args){
方法main应该是静态的！ ： - ）