我的程序使用日期来检查工程师何时访问了计算机。唯一的问题是日期不是最新的。机器显示的日期和时间是机器启动的确切时间。不是单击按钮时。任何帮助都会有所帮助。
代码：
package com.perisic.beds.peripherals;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintStream;
import java.lang.management.ManagementFactory;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Vector;
import javax.swing.*;
import org.apache.xmlrpc.WebServer;
import org.apache.xmlrpc.XmlRpcClient;
import com.perisic.beds.machine.CustomerPanel;
/**
* A Simple Graphical User Interface for the Recycling Machine.
* @author Group M
*
*/
public class RecyclingGUI extends JFrame implements ActionListener {
/**
*
*/
private static final long serialVersionUID = -5772727482959492839L;
//CustomerPanel myCustomerPanel = new CustomerPanel(new Display());
Display myDisplay = new Display();
ReceiptPrinter printer = new ReceiptPrinter();
ReceiptPrinter printer2 = new ReceiptPrinter();
CustomerPanel myCustomerPanel = new CustomerPanel(myDisplay);
CustomerPanel machineScreen = new CustomerPanel(printer2);
CustomerPanel theConsole = new CustomerPanel(printer);
CustomerPanel thePanel = new CustomerPanel(myDisplay);
private String storedPasswd = "123"; // needs some thinking with encryption etc
private String storedCookie = null; // some random string to be used for authentication
private String sessionCookie = "";
private int numberOfVisits;
DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy HH:mm");
Date date = new Date();
Date storedDate = date;
/**
* Web service to provide number of items in the machine.
* @param myCookie
* @return
*/
public int numberOfItems(String myCookie) {
if( storedCookie == null ) {
return -1;
} else if( myCookie.equals(storedCookie)) {
return myCustomerPanel.getNumberOfItems();
}
else {
return -1;
}
}
public int empty (String myCookie){
if(storedCookie == null){
return -1;
}else if(myCookie.equals(storedCookie)){
return myCustomerPanel.empty();
}else{
return -1;
}
}
/**
* Web service to authenticate the user with proper password.
* @param passwd
* @return
*/
public String login(String passwd) {
if( passwd.equals(storedPasswd)) {
storedCookie = "MC"+Math.random();
System.out.println("Engineer has logged in on: " + dateFormat.format(date));
storedDate = date;
numberOfVisits ++;
return storedCookie;
} else {
return "Incorrect Password";
}
}
public String visits(String myCookie){
if(numberOfVisits == 0){
return "Engineer has not visited this machine";
}else if(myCookie.equals(storedCookie)){
for(int i = 0; i < numberOfVisits; i++){
System.out.println("Engineer has visited on these dates: " + dateFormat.format(storedDate));
}
return storedCookie;
}else{
return "Engineer has visited on these date: " + dateFormat.format(storedDate);
}
}
/**
* Web service to logout from the system.
*/
public String logout(String myCookie ) {
if( storedCookie == null ) {
return "(no cookie set)";
} else if( myCookie.equals(storedCookie)) {
System.out.println("Engineer has logged out on: " + dateFormat.format(date));
storedCookie = null;
return "cookie deleted: OK";
}
else {
return "could not delete anything; authentication missing";
}
}
public static final String SUN_JAVA_COMMAND = "sun.java.command";
//This method is used to restart the application.
//It uses code that basically stores all of the necessary code it will need to successfully restart the application.
//Rather then just using System.exit(0) which, by itself would simply close the entire application.
//Using dispose() and new RecyclingGUI also doesn't work as it does not reload the JPanel upon restarting.
public void restartApplication(Runnable runBeforeRestart) throws IOException{
try {
String java = System.getProperty("java.home") + "/bin/java";
List<String> vmArguments = ManagementFactory.getRuntimeMXBean().getInputArguments();
StringBuffer vmArgsOneLine = new StringBuffer();
for (String arg : vmArguments) {
if (!arg.contains("-agentlib")) {
vmArgsOneLine.append(arg);
vmArgsOneLine.append(" ");
}
}
final StringBuffer cmd = new StringBuffer("\"" + java + "\" " + vmArgsOneLine);
String[] mainCommand = System.getProperty(SUN_JAVA_COMMAND).split(" ");
if (mainCommand[0].endsWith(".jar")) {
cmd.append("-jar " + new File(mainCommand[0]).getPath());
} else {
cmd.append("-cp \"" + System.getProperty("java.class.path") + "\" " + mainCommand[0]);
}
for (int i = 1; i < mainCommand.length; i++) {
cmd.append(" ");
cmd.append(mainCommand[i]);
}
Runtime.getRuntime().addShutdownHook(new Thread() {
@Override
public void run() {
try {
Runtime.getRuntime().exec(cmd.toString());
} catch (IOException e) {
e.printStackTrace();
}
}
});
if (runBeforeRestart!= null) {
runBeforeRestart.run();
}
System.exit(0);
} catch (Exception e) {
throw new IOException("Error while trying to restart the machine", e);
}
}
public void actionPerformed(ActionEvent e) {
/* Differentiate between the different buttons pressed and initiate appropriate
* actions
*/
try{
XmlRpcClient server = new XmlRpcClient("http://localhost:100");
//This code allows the engineer to login to the machine and when they do it reveals new buttons that only the engineer can use.
if (e.getSource().equals(login)){
String message;
boolean loginSuccess = false;
while(loginSuccess == false && (message = JOptionPane.showInputDialog("Login please"))!= null){
Vector parms1 = new Vector();
parms1.add(message);
Object result3 = server.execute("recycling.login", parms1);
String loginRequest = result3.toString();
if(loginRequest.equals("Wrong password")){
System.out.println("Wrong Password. Try Again!");
} else {
sessionCookie = loginRequest;
System.out.println("You are now logged in");
login.setVisible(false);
logout.setVisible(true);
reset.setVisible(true);
empty.setVisible(true);
items.setVisible(true);
loginSuccess = true;
}
}
}else if(e.getSource().equals(visits)){
Vector params = new Vector();
params.add(sessionCookie);
Object result = server.execute("recycling.visits", params);
System.out.println(result);
//This logs the engineer out of the machine and hides some of the buttons
}else if( e.getSource().equals(logout)) {
Vector params = new Vector();
params.add(sessionCookie);
Object result = server.execute("recycling.logout", params );
System.out.println("Logout: "+result);
reset.setVisible(false);
empty.setVisible(false);
items.setVisible(false);
login.setVisible(true);
logout.setVisible(false);
//This code tells the engineer how many items are currently in the machine.
}else if(e.getSource().equals(items)){
Vector params = new Vector();
params.add(sessionCookie);
Object result = server.execute("recycling.numberOfItems", params );
int resultInt = new Integer(result.toString());
if( resultInt == -1 ) {
System.out.println("Sorry no authentication there.");
} else {
System.out.println("There are "+resultInt+" items in the machine");
}
//This if statement empties all items that have been put into the machine thus far and sets the item number property to 0
}else if(e.getSource().equals(empty)){
Vector params = new Vector();
params.add(sessionCookie);
Object result = server.execute("recycling.empty", params);
int resultInt = new Integer(result.toString());
if(resultInt == -1){
System.out.println("Sorry no authentication there.");
}else{
System.out.println("The machine has been emptied.");
}
//This method coded above is called here.
}else if(e.getSource().equals(reset)){
restartApplication(null);
}else if(e.getSource().equals(slot1)) {
myCustomerPanel.itemReceived(1);
}else if(e.getSource().equals(slot2)) {
myCustomerPanel.itemReceived(2);
}else if(e.getSource().equals(slot3)) {
myCustomerPanel.itemReceived(3);
}else if(e.getSource().equals(slot4)) {
myCustomerPanel.itemReceived(4);
}else if(e.getSource().equals(receipt)) {
myCustomerPanel.printReceipt();
}else if(e.getSource().equals(display)) {
this.myCustomerPanel = thePanel;
}else if(e.getSource().equals(console)){
myCustomerPanel = theConsole;
}else if(e.getSource().equals(onScreen)){
//once this button is clicked all output is linked back into the GUI
myCustomerPanel = machineScreen;
redirectSystemStreams();
}
}catch (Exception exception) {
System.err.println("JavaClient: " + exception);
}
// System.out.println("Received: e.getActionCommand()="+e.getActionCommand()+
// " e.getSource()="+e.getSource().toString() );
}
//This Adds the controls (buttons) to the GUI
JButton slot1 = new JButton("Can");
JButton slot2 = new JButton("Bottle");
JButton slot3 = new JButton("Crate");
JButton slot4 = new JButton("Paper Bag");
JButton receipt = new JButton("Print Receipt");
JButton login = new JButton("Login");
JButton logout = new JButton("Logout");
JButton reset = new JButton("Reset");
JButton empty = new JButton("Empty");
JButton items = new JButton("#Items");
JButton visits = new JButton("visits");
JTextArea textArea = new JTextArea(20,30);
JScrollPane scroll = new JScrollPane(textArea);
JButton display = new JButton("Print to Display");
JButton console = new JButton("Print to GUI/Console");
JButton onScreen = new JButton("Show On Screen");
/** This creates the GUI using the controls above and
* adds the actions and listeners. this area of code also
* Contains the panel settings for size and some behaviours.
*/
public RecyclingGUI() {
super();
setSize(500, 600);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
panel.add(slot1);
panel.add(slot2);
panel.add(slot3);
panel.add(slot4);
slot1.addActionListener(this);
slot2.addActionListener(this);
slot3.addActionListener(this);
slot4.addActionListener(this);
panel.add(receipt);
receipt.addActionListener(this);
panel.add(display);
display.addActionListener(this);
panel.add(console);
console.addActionListener(this);
panel.add(onScreen);
onScreen.addActionListener(this);
/**Text Area controls for size, font style, font size
* the text area also has a scroll bar just in case the user enters
* a large number of items
*/
panel.add(scroll);
textArea.setLineWrap(true);
textArea.setEditable(false);
textArea.setFont(new Font("Ariel",Font.PLAIN, 14));
scroll.setPreferredSize(new Dimension(450, 450));
scroll.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
panel.add(login);
login.addActionListener(this);
panel.add(logout);
logout.setVisible(false);
logout.addActionListener(this);
panel.add(reset);
reset.setVisible(false);
reset.addActionListener(this);
panel.add(items);
items.setVisible(false);
items.addActionListener(this);
panel.add(empty);
empty.setVisible(false);
empty.addActionListener(this);
panel.add(visits);
visits.addActionListener(this);
getContentPane().add(panel);
panel.repaint();
}
public static void main(String [] args ) {
RecyclingGUI myGUI = new RecyclingGUI();
myGUI.setVisible(true);
try {
System.out.println("Starting the Recycling Server...");
WebServer server = new WebServer(100);
server.addHandler("recycling", myGUI);
server.start();
} catch (Exception exception) {
System.err.println("JavaServer: " + exception);
}
}
/** This is the code that redirects where the code is displayed
* from the console to the textArea of the GUI. it does this by
* creating a new set of output streams (for text and errors) which
* are set as default when the redirectSystemStream method is called.
* (from a previous piece of work i did in my FDg, source = from a tutorial)
*/
public void updateTextArea(final String text) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
textArea.append(text);
}
});
}
public void redirectSystemStreams() {
OutputStream out = new OutputStream() {
@Override
public void write(int b) throws IOException {
updateTextArea(String.valueOf((char) b));
}
@Override
public void write(byte[] b, int off, int len) throws IOException {
updateTextArea(new String(b, off, len));
}
@Override
public void write(byte[] b) throws IOException {
write(b, 0, b.length);
}
};
System.setOut(new PrintStream(out, true));
System.setErr(new PrintStream(out, true));
}
public void print(String str) {
System.out.println(str);
}
}
答案 0 :(得分：2)
您永远不会重新初始化date，而只是使用storedDate中的现有 date更新login。您可以在login
storedDate = date;
到
storedDate = new Date();
然后（我认为）你可以删除date。
答案 1 :(得分：1)
Date没有保持持续的当前时间。 Date由long支持，Date在new Date()实例化时设置且永不更改。
您可以在登录方法中生成System.currentTimeMillis()，这样就可以在用户登录时创建，或者只使用long将当前时间设为{{1}}。