在同一目录下编译成功的两个文件,一个可运行一个不行??

Question

编译并运行以下(正常):
public class HelloWorld{
public static void main(String[] args){
System.out.println("Hello,World!");
}
} 
编译(正常)并运行一个有背景图的,提示:
(Exception in thread "main" java.lang.NoSuchMethodError: main)
为什么??
两个文件在同一目录下.

Answer 1

要将编译好的class文件考到该文件的package包为名的文件夹里
再运行

Answer 2

用javac?
是不是一个有包，一个没有包啊

Answer 3

两个都是经过javac处理成.class的,但一个可以用java HelloWord运行,另一个却提示:
Exception in thread "main" java.lang.NoSuchMethodError: main

Answer 4

如果配置在C盘，可以直接在DOS下用JAVAC把文件的路径写清楚。

Answer 5

我的jsdk在C盘,tomcat 5.0在D盘..
写明了呀.

Answer 6

你那个程序有没有main()函数啊?

Answer 7

hgf1011(hgf) 
你那个程序有没有main()函数啊?
支持

Answer 8

你那个程序有没有main()函数啊?

Answer 9

别人都可以编译成可运行程序，，为什么我的不行呢？？？在哪里看有没main()

Answer 10

/*
chatroom类
登陆界面
2005/03/17
*/
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.net.*;
import java.util.*;
import java.util.Calendar;
import java.util.GregorianCalendar;public class chatroom extends JApplet
{
String         MyPath;       //路径
JPanel         plogin;       //显示登陆界面
JLabel         picture;      //显示图片

JLabel         lname;        //用户名字
JLabel         lpass;        //用户密码字
JTextField     tname;        //用户文本框
JPasswordField tpass;        //用户密码框

JButton        bsubmit;      //用户登陆
JButton        breg;         //用户注册

JLabel         ltext;        //聊天室状态
JLabel         lcount;       //聊天室人数
JLabel         ladmin;       //聊天室管理
JLabel         ladminname;   //聊天室管理人员
reg            r;            //用户注册界面 public void init()
{
MyPath = getCodeBase().getPath();
MyStyle();    //设置样式
plogin = new JPanel();
plogin.setLayout(null);
plogin.setBackground(Color.white);
getContentPane().add(plogin);
//设计程序面版
setSize(new Dimension(300,300));
//开始设计控件样式
picture = new JLabel(new ImageIcon(MyPath+"//img//logo.jpg"));
picture.setLocation(0,0);
picture.setSize(300,300);

lname = new JLabel("帐号:");
lname.setSize(50,20);
lname.setLocation(130,160);

tname = new JTextField();
tname.setSize(85,18);
tname.setLocation(165,161);
tname.setCaretPosition(0);
tname.setCaretColor(Color.decode("#FF2222"));
tname.setSelectedTextColor(Color.white);
tname.setSelectionColor(Color.decode("#ff9999"));

lpass = new JLabel("密码:");
lpass.setSize(50,20);
lpass.setLocation(130,184);

tpass = new JPasswordField();
tpass.setSize(85,18);
tpass.setLocation(165,185);
tpass.setCaretColor(Color.decode("#FF2222"));
tpass.setSelectedTextColor(Color.white);
tpass.setSelectionColor(Color.decode("#ff9999"));

bsubmit = new JButton();
bsubmit.setIcon(new ImageIcon(MyPath+"//img//bsubmit.jpg"));
bsubmit.setSize(55,24);
bsubmit.setBorderPainted(false);
bsubmit.setLocation(145,210);
bsubmit.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));

breg = new JButton();
breg.setIcon(new ImageIcon(MyPath+"//img//breg.jpg"));
breg.addActionListener(new UserReg());
breg.setSize(55,24);
breg.setBorderPainted(false);
breg.setLocation(200,210);
breg.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));

ltext  = new JLabel("聊天室:");
ltext.setSize(50,20);
ltext.setLocation(25,125);
lcount = new JLabel("在线人数 0 人");
lcount.setSize(100,20);
lcount.setLocation(35,140);
ladmin = new JLabel("管理员:");
ladmin.setSize(100,20);
ladmin.setLocation(25,160);
ladminname = new JLabel("陈源,熊昌恒");
ladminname.setSize(100,20);
ladminname.setLocation(35,175);

//开始加载控件
plogin.add(lpass);
plogin.add(tpass);
plogin.add(bsubmit);
plogin.add(breg);
plogin.add(lname);
plogin.add(tname);

plogin.add(ltext);
plogin.add(lcount);
plogin.add(ladmin);
plogin.add(ladminname);

plogin.add(picture);
}
class UserReg implements ActionListener
{
public void actionPerformed(ActionEvent evt)
{
r = new reg();
breg.setVisible(false);
r.setVisible(true);
}
}
//用户注册界面
public class reg extends Frame implements Runnable
{
Thread      reg_showdate;     //显示时间的线程
Date        reg_date;
GregorianCalendar reg_calendar;
JLabel      reg_ldate;

Panel       reg_p;
JLabel      reg_limg;
//          姓名      密码      确认密码    年龄     邮件
JLabel      reg_lname,reg_lpass,reg_lrepass,reg_lage,reg_lmail;
JLabel      reg_hname,reg_hpass,reg_hrepass,reg_hage,reg_hmail;   //帮助说明
JTextField  reg_tname,reg_tage,reg_tmail;
JPasswordField reg_tpass,reg_trepass;
//爱好
JLabel      reg_llike;
JTextArea   reg_tlike;
//性别
JLabel      reg_lsex,reg_hsex;
JComboBox   reg_csex;
//注册,重置
JButton     reg_breg,reg_bresize;

Answer 11

public reg()
{
//MyStyle();
super.setTitle("注册用户:");
super.setBounds(0,0,304,542);
super.setResizable(false);

//关闭Frame
this.addWindowListener(
new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
reg.this.windowClosed();
}
}
);
reg_p = new Panel();
reg_p.setLayout(null);
this.add(reg_p);

//前文本
reg_limg = new JLabel(new ImageIcon(MyPath+"//img//reg.jpg"));
reg_limg.setSize(300,500);
reg_limg.setLocation(0,0);

reg_lname = new JLabel("姓名:");
reg_lname.setSize(50,20);
reg_lname.setLocation(30,120);

reg_lpass = new JLabel("密码:");
reg_lpass.setSize(50,20);
reg_lpass.setLocation(30,150);

reg_lrepass = new JLabel("重复密码:");
reg_lrepass.setSize(80,20);
reg_lrepass.setLocation(30,180);

reg_lage = new JLabel("年龄:");
reg_lage.setSize(50,20);
reg_lage.setLocation(30,210);

reg_lsex = new JLabel("性别:");
reg_lsex.setSize(50,20);
reg_lsex.setLocation(30,240);

reg_lmail = new JLabel("邮箱地址:");
reg_lmail.setSize(80,20);
reg_lmail.setLocation(30,270);

reg_llike = new JLabel("个人爱好: *100个字符内");
reg_llike.setSize(200,20);
reg_llike.setLocation(30,310);

//加入控件
reg_tname = new JTextField();
reg_tname.setSize(100,18);
reg_tname.setLocation(90,121);
reg_tname.setCaretColor(Color.decode("#FF2222"));
reg_tname.setSelectedTextColor(Color.white);
reg_tname.setSelectionColor(Color.decode("#ff9999"));

reg_tpass = new JPasswordField();
reg_tpass.setSize(100,18);
reg_tpass.setLocation(90,151);
reg_tpass.setCaretColor(Color.decode("#FF2222"));
reg_tpass.setSelectedTextColor(Color.white);
reg_tpass.setSelectionColor(Color.decode("#ff9999"));

reg_trepass = new JPasswordField();
reg_trepass.setSize(100,18);
reg_trepass.setLocation(90,181);
reg_trepass.setCaretColor(Color.decode("#FF2222"));
reg_trepass.setSelectedTextColor(Color.white);
reg_trepass.setSelectionColor(Color.decode("#ff9999"));

reg_tage = new JTextField();
reg_tage.setSize(45,18);
reg_tage.setLocation(90,211);
reg_tage.setCaretColor(Color.decode("#FF2222"));
reg_tage.setSelectedTextColor(Color.white);
reg_tage.setSelectionColor(Color.decode("#ff9999"));

String[] ssex = {"男","女"};
reg_csex = new JComboBox(ssex);
reg_csex.setSize(45,20);
reg_csex.setLocation(90,240);
reg_csex.setFont(new Font("宋体",Font.PLAIN,12));
reg_csex.setForeground(Color.decode("#ff6666"));
reg_csex.setBorder(BorderFactory.createLineBorder(Color.decode("#ffffff"),1));
reg_csex.setBackground(Color.white);

reg_tmail = new JTextField();
reg_tmail.setSize(150,18);
reg_tmail.setLocation(90,271);
reg_tmail.setCaretColor(Color.decode("#FF2222"));
reg_tmail.setSelectedTextColor(Color.white);
reg_tmail.setSelectionColor(Color.decode("#ff9999"));
reg_tmail.setText("@");

reg_tlike = new JTextArea();
reg_tlike.setSize(210,90);
reg_tlike.setLocation(30,330);
reg_tlike.setCaretColor(Color.decode("#FF2222"));
reg_tlike.setSelectedTextColor(Color.white);
reg_tlike.setSelectionColor(Color.decode("#ff9999"));

//加入说明
reg_hname = new JLabel("*请输入字符");
reg_hname.setSize(100,20);
reg_hname.setLocation(195,120);

reg_hpass = new JLabel("*范围6-16位");
reg_hpass.setSize(100,20);
reg_hpass.setLocation(195,150);

reg_hrepass = new JLabel("*同上一样");
reg_hrepass.setSize(100,20);
reg_hrepass.setLocation(195,180);

reg_hage = new JLabel("*大小10-80岁");
reg_hage.setSize(100,20);
reg_hage.setLocation(195,210);

reg_hsex = new JLabel("*请选择");
reg_hsex.setSize(100,20);
reg_hsex.setLocation(195,240);

reg_hmail = new JLabel("*请输入有效的邮箱地址.如:[email protected]");
reg_hmail.setSize(200,20);
reg_hmail.setLocation(90,290);



//加入按钮
reg_breg = new JButton();
reg_breg.setIcon(new ImageIcon(MyPath+"//img//breg.jpg"));
reg_breg.setSize(55,24);
reg_breg.setBorderPainted(false);
reg_breg.setLocation(80,425);
reg_breg.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));

reg_bresize = new JButton();
reg_bresize.setIcon(new ImageIcon(MyPath+"//img//bresize.jpg"));
reg_bresize.setSize(55,24);
reg_bresize.setBorderPainted(false);
reg_bresize.setLocation(140,425);
reg_bresize.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
reg_bresize.addActionListener(new ReSize());

//加入时间
reg_ldate = new JLabel();
reg_ldate.setSize(200,20);
reg_ldate.setLocation(20,465);

reg_p.add(reg_lname);
reg_p.add(reg_lpass);
reg_p.add(reg_lrepass);
reg_p.add(reg_lage);
reg_p.add(reg_lsex);
reg_p.add(reg_lmail);
reg_p.add(reg_llike);

reg_p.add(reg_tname);
reg_p.add(reg_tpass);
reg_p.add(reg_trepass);
reg_p.add(reg_tage);
reg_p.add(reg_csex);
reg_p.add(reg_tmail);
reg_p.add(reg_tlike);

reg_p.add(reg_hname);
reg_p.add(reg_hpass);
reg_p.add(reg_hrepass);
reg_p.add(reg_hage);
reg_p.add(reg_hsex);
reg_p.add(reg_hmail);

reg_p.add(reg_breg);
reg_p.add(reg_bresize);

reg_p.add(reg_ldate);

reg_p.add(reg_limg);


//显示时间
reg_showdate = new Thread(this);
reg_showdate.start();
}
protected void windowClosed()
{
//退出窗口
breg.setVisible(true);
super.dispose();
}
class ReSize implements ActionListener
{
public void actionPerformed(ActionEvent evt)
{
reg_tname.setText("");
reg_tpass.setText("");
reg_trepass.setText("");
reg_tage.setText("");
reg_tmail.setText("@");
reg_tlike.setText("");
}
}
public void run()
{
while(reg_showdate != null)
{
display();
try
{
reg_showdate.sleep(1000);
}
catch(InterruptedException e)
{
reg_ldate.setText("无法显示");
}
}
}
public void display()
{
reg_date = new Date();
reg_calendar = new GregorianCalendar();
String mydates;
mydates = reg_calendar.get(Calendar.YEAR)+"年"+(reg_calendar.get(Calendar.MONTH)+1)+"月"+reg_calendar.get(Calendar.DATE);
mydates += " ";
mydates += reg_calendar.get(Calendar.HOUR)+":"+reg_calendar.get(Calendar.MINUTE)+":"+reg_calendar.get(Calendar.SECOND);

reg_ldate.setText(mydates);
}
}
//公共样式类
public static void MyStyle()
{
//Label样式
UIManager.put("Label.font",new Font("宋体",Font.PLAIN,12));
UIManager.put("Label.foreground",Color.decode("#ff6666"));
//TextField样式
UIManager.put("TextField.font",new Font("宋体",0,12));
UIManager.put("TextField.foreground",Color.decode("#ff6666"));
UIManager.put("TextField.border",BorderFactory.createLineBorder(Color.decode("#ff9999"),1));
//PasswordField
UIManager.put("PasswordField.font",new Font("宋体",0,12));
UIManager.put("PasswordField.foreground",Color.decode("#ff6666"));
UIManager.put("PasswordField.border",BorderFactory.createLineBorder(Color.decode("#ff9999"),1));
//TextArea
UIManager.put("TextArea.font",new Font("宋体",0,12));
UIManager.put("TextArea.foreground",Color.decode("#ff6666"));
UIManager.put("TextArea.border",BorderFactory.createLineBorder(Color.decode("#ff9999"),1));
}
}