1、Integer.parseInt(amount); 如果抛出异常就不是数字；
创新互联建站坚持“要么做到，要么别承诺”的工作理念，服务领域包括：网站设计制作、网站建设、企业官网、英文网站、手机端网站、网站推广等服务，满足客户于互联网时代的昭阳网站设计、移动媒体设计的需求，帮助企业找到有效的互联网解决方案。努力成为您成熟可靠的网络建设合作伙伴！
2、amount.matches("[\\d]+"); 正则表达式匹配全数字，不是返回false
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class AccountDemo {
public static double MONEY = 0;// 初始化金额是100元。
public static void main(String[] args) {
final String USER_NAME = "zhangsan";// 用户名
final String PASSWORD = "123456";// 密码
while (true) {
System.out.print("请输入用户名：");
String user_name = getString();
System.out.print("请输入密码：");
String password = getString();
if (user_name != null user_name.equals(USER_NAME)
password != null password.equals(PASSWORD)) {
System.out.println("登陆成功！你要干什么？");
while (true) {
System.out.println("1：存款");
System.out.println("2：取款");
System.out.println("3：查询余额");
System.out.println("q：退出程序");
System.out.print("请选择：");
String userIn = getString();
int in = 0;
if (userIn != null userIn.equals("1")) {
in = Integer.parseInt(userIn);
} else if (userIn != null userIn.equals("2")) {
in = Integer.parseInt(userIn);
} else if (userIn != null userIn.equals("3")) {
in = Integer.parseInt(userIn);
} else if (userIn != null
userIn.trim().toUpperCase().equals("Q")) {
in = 4;
} else {
System.out.println("你输入的指令不正确！请重新输入。");
continue;
}
switch (in) {
case 1:
double add_money = 0;
while (true) {
System.out.print("请输入你要存入的金额：");
try {
add_money = Double.parseDouble(getString());
} catch (Exception e) {
System.out.println("金额输入不正确！");
continue;
}
break;
}
MONEY += add_money;
System.out.println("存入的金额是" + add_money
+ "\r\n请选择你要的操作：");
break;
case 2:
double money = 0;
while (true) {
System.out.print("请输入你要取出的金额：");
try {
money = Double.parseDouble(getString());
} catch (Exception e) {
System.out.println("金额输入不正确！");
continue;
}
if (money MONEY) {
System.out.println("取出的金额大于现有存款，请重新输入要取出的金额！");
continue;
}
break;
}
MONEY -= money;
System.out.println("取出的金额是" + money + "\r\n请选择你要的操作：");
break;
case 3:
System.out.println("你的余额是：" + MONEY + "\r\n请选择你要的操作：");
break;
case 4:
System.out.println("程序退出！");
return;
}
}
} else {
System.out.println("错误：用户名与密码不匹配！\r\n");
System.out.println("按任意键:重新输入用户名和密码。");
System.out.println("q:退出程序。");
System.out.print("请选择:");
String in = getString();
if (in.trim().toUpperCase().equals("Q")) {
break;
}
}
}
}
public static String getString() {
String str = null;
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
try {
str = br.readLine();
} catch (IOException e) {
e.printStackTrace();
}
return str;
}
}
package untitled5;
import java.io.*;
import java.net.*;
import java.sql.*;
import java.lang.*;
import javax.sql.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import com.borland.jbcl.layout.*;
public class delbook extends JFrame {
JPanel contentPane;
XYLayout xYLayout1 = new XYLayout();
JLabel jLabel1 = new JLabel();
JLabel jLabel2 = new JLabel();
JLabel jLabel3 = new JLabel();
JTextField jTextField1 = new JTextField();
JLabel jLabel4 = new JLabel();
JTextField jTextField2 = new JTextField();
JLabel jLabel5 = new JLabel();
JTextField jTextField3 = new JTextField();
JLabel jLabel6 = new JLabel();
JTextField jTextField4 = new JTextField();
JButton jButton1 = new JButton();
//Construct the frame
public delbook() {
enableEvents(AWTEvent.WINDOW_EVENT_MASK);
try {
jbInit();
}
catch(Exception e) {
e.printStackTrace();
}
}
//Component initialization
private void jbInit() throws Exception {
contentPane = (JPanel) this.getContentPane();
jLabel1.setFont(new java.awt.Font("SansSerif", 0, 25));
jLabel1.setForeground(Color.red);
jLabel1.setText("超市管理系统");
contentPane.setLayout(xYLayout1);
this.setSize(new Dimension(500,400));
this.setTitle("超市管理系统");
jLabel2.setFont(new java.awt.Font("SansSerif", 0, 30));
jLabel2.setText("业务单位信息");
jLabel3.setFont(new java.awt.Font("SansSerif", 0, 25));
jLabel3.setText("产品编号");
jTextField1.setText("");
jLabel4.setFont(new java.awt.Font("SansSerif", 0, 25));
jLabel4.setText("公司名称");
jTextField2.setText("");
jLabel5.setFont(new java.awt.Font("SansSerif", 0, 25));
jLabel5.setText("订单号码");
jTextField3.setText("");
jLabel6.setFont(new java.awt.Font("SansSerif", 0, 25));
jLabel6.setText("电 话");
jTextField4.setText("");
jButton1.setFont(new java.awt.Font("SansSerif", 0, 25));
jButton1.setText("提交");
jButton1.addActionListener(new delbook_jButton1_actionAdapter(this));
contentPane.add(jLabel1, new XYConstraints(179, 1, 153, 32));
contentPane.add(jLabel2, new XYConstraints(162, 33, -1, -1));
contentPane.add(jLabel3, new XYConstraints(83, 89, -1, -1));
contentPane.add(jTextField1, new XYConstraints(189, 88, 141, 36));
contentPane.add(jTextField2, new XYConstraints(189, 149, 142, 36));
contentPane.add(jLabel4, new XYConstraints(84, 148, -1, -1));
contentPane.add(jTextField3, new XYConstraints(188, 206, 143, 33));
contentPane.add(jLabel5, new XYConstraints(84, 204, -1, -1));
contentPane.add(jLabel6, new XYConstraints(84, 253, -1, -1));
contentPane.add(jTextField4, new XYConstraints(189, 260, 143, 36));
contentPane.add(jButton1, new XYConstraints(197, 318, -1, -1));
}
//Overridden so we can exit when window is closed
protected void processWindowEvent(WindowEvent e) {
super.processWindowEvent(e);
if (e.getID() == WindowEvent.WINDOW_CLOSING) {
System.exit(0);
}
}
void update() {
try {
//定义显示的字符串
String str1;
String str2;
String str3;
String str4;
str1 = jTextField1.getText();
str2 = jTextField2.getText();
str3 = jTextField3.getText();
str4 = jTextField4.getText();
//装载jdbc驱动程序
String driverName = "oracle.jdbc.OracleDriver";
Driver driver = (Driver) Class.forName(driverName).newInstance();
//连接数据库
Connection con = DriverManager.getConnection(
"jdbc:oracle:thin:@thsspc0791:1521:liuyong", "hr", "tongfang");
PreparedStatement pstmt = con.prepareStatement(
" insert Customer1('goodID','Name','PID','tel')values(?,?,?,?)");
pstmt.setString(1, str1);
pstmt.setString(2, str2);
pstmt.setString(1, str3);
pstmt.setString(4, str4);
ResultSet res = pstmt.executeQuery();
pstmt.close();
con.close();
}catch (InstantiationException e) {
System.out.println(e.getMessage());
}catch (IllegalAccessException e) {
System.out.println(e.getMessage());
}catch (ClassNotFoundException e) {
System.out.println(e.getMessage());
}catch (SQLException edd) {
edd.printStackTrace() ;
System.out.println(edd.getMessage());
}
}
void jButton1_actionPerformed(ActionEvent e) {
update();
}
}
class delbook_jButton1_actionAdapter implements java.awt.event.ActionListener {
delbook adaptee;
delbook_jButton1_actionAdapter(delbook adaptee) {
this.adaptee = adaptee;
}
public void actionPerformed(ActionEvent e) {
adaptee.jButton1_actionPerformed(e);
}
}
package untitled5;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import com.borland.jbcl.layout.*;
/**
* pTitle: /p
* pDescription: /p
* pCopyright: Copyright © 2003/p
* pCompany: /p
* @author not attributable
* @version 1.0
*/
public class retur extends JFrame {
JPanel contentPane;
XYLayout xYLayout1 = new XYLayout();
JLabel jLabel1 = new JLabel();
//Construct the frame
public retur() {
enableEvents(AWTEvent.WINDOW_EVENT_MASK);
try {
jbInit();
}
catch(Exception e) {
e.printStackTrace();
}
}
//Component initialization
private void jbInit() throws Exception {
contentPane = (JPanel) this.getContentPane();
jLabel1.setFont(new java.awt.Font("SansSerif", 0, 20));
jLabel1.setForeground(Color.red);
jLabel1.setText("超市管理系统");
contentPane.setLayout(xYLayout1);
this.setSize(new Dimension(400, 300));
this.setTitle("超市管理系统");
contentPane.add(jLabel1, new XYConstraints(139, 1, 126, 33));
}
//Overridden so we can exit when window is closed
protected void processWindowEvent(WindowEvent e) {
super.processWindowEvent(e);
if (e.getID() == WindowEvent.WINDOW_CLOSING) {
System.exit(0);
}
}
}
package untitled5;
import java.io.*;
import java.net.*;
import java.sql.*;
import java.lang.*;
import javax.sql.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import com.borland.jbcl.layout.*;
import com.borland.dbswing.*;
//货品信息登记
public class Frame2 extends JFrame {
JPanel contentPane;
JLabel jLabel1 = new JLabel();
XYLayout xYLayout1 = new XYLayout();
JLabel jLabel2 = new JLabel();
JLabel jLabel3 = new JLabel();
JTextField jTextField1 = new JTextField();
JLabel jLabel4 = new JLabel();
JTextField jTextField2 = new JTextField();
JPanel jPanel1 = new JPanel();
XYLayout xYLayout2 = new XYLayout();
JScrollPane jScrollPane1 = new JScrollPane();
JLabel jLabel5 = new JLabel();
JTextField jTextField3 = new JTextField();
//Construct the frame
public Frame2() {
enableEvents(AWTEvent.WINDOW_EVENT_MASK);
try {
jbInit();
}
catch(Exception e) {
e.printStackTrace();
}
}
//Component initialization
private void jbInit() throws Exception {
contentPane = (JPanel) this.getContentPane();
contentPane.setLayout(xYLayout1);
this.setSize(new Dimension(600, 500));
this.setTitle("超市管理系统");
this.addHierarchyBoundsListener(new Frame2_this_hierarchyBoundsAdapter(this));
jLabel1.setFont(new java.awt.Font("SansSerif", 0, 25));
jLabel1.setForeground(Color.red);
jLabel1.setText("超市管理系统");
contentPane.setForeground(Color.black);
jLabel2.setFont(new java.awt.Font("SansSerif", 0, 30));
jLabel2.setText("产 品 信 息 展 示");
// statusBar.setFont(new java.awt.Font("SansSerif", 0, 20));
jLabel3.setFont(new java.awt.Font("SansSerif", 0, 20));
jLabel3.setText("产品名称");
jTextField1.setText("");
jLabel4.setEnabled(true);
jLabel4.setFont(new java.awt.Font("SansSerif", 0, 20));
jLabel4.setText("产品ID号");
jTextField2.setText("");
jTextField2.addActionListener(new Frame2_jTextField2_actionAdapter(this));
jPanel1.setLayout(xYLayout2);
jLabel5.setFont(new java.awt.Font("SansSerif", 0, 25));
jLabel5.setForeground(Color.red);
jLabel5.setText("该产品详细信息");
jTextField3.setText("");
contentPane.add(jLabel1, new XYConstraints(237, 0, 153, 40));
contentPane.add(jLabel2, new XYConstraints(200, 47, 231, 58));
contentPane.add(jLabel3, new XYConstraints(47, 102, 101, 42));
contentPane.add(jTextField1, new XYConstraints(128, 108, 112, 34));
contentPane.add(jTextField2, new XYConstraints(361, 107, 109, 36));
contentPane.add(jPanel1, new XYConstraints(75, 166, 453, 277));
jPanel1.add(jScrollPane1, new XYConstraints(14, 8, 433, 221));
jScrollPane1.getViewport().add(jTextField3, null);
jPanel1.add(jLabel5, new XYConstraints(112, 240, -1, -1));
contentPane.add(jLabel4, new XYConstraints(278, 111, -1, -1));
}
//Overridden so we can exit when window is closed
protected void processWindowEvent(WindowEvent e) {
super.processWindowEvent(e);
if (e.getID() == WindowEvent.WINDOW_CLOSING) {
System.exit(0);
}
}
void Select() {
try {
String str1, str2;
str1 = jTextField1.getText();
str2 = jTextField2.getText();
1，java规范中一般不建议一个java类中超过500行
2，一行的长度不超过200个
3，按照规定格式将代码格式化
