我有一个Putty终端，我读了一个字符串，f.ex。如果我在4中打印，我得到一个看起来像这样的字符串（ ' 4）有人知道，我怎么能提取这个4？我用模式和匹配器尝试了它。但它仍然无效。
我正在制作带插座的餐厅服务器，用于餐厅。代码有点多，但我希望你不会因为粘贴我的每一堂课而讨厌我。
服务器类：
package Ue1SpeiseServer;
import java.io.IOException;
import java.net.ServerSocket;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class RestaurantTrekNation {
/**
* The Port for the Server
*/
private static Scanner sc = new Scanner(System.in);
private static int PORT;
/**
* A Arraylist with all Clients
*/
protected static List<Customer> customers = new ArrayList<>();
protected static int[] tables = new int[5];
public static List<Dish> menu = new ArrayList<>();
static {
menu.add(new Dish(1,19.99, "hello" , 5));
menu.add(new Dish(2,0.99, "hello" , 5));
menu.add(new Dish(3,10.99, "hello" , 5));
menu.add(new Dish(4,13.45, "hello" , 5));
menu.add(new Dish(5,12.95, "hello" , 5));
menu.add(new Dish(6,08.00, "hello" , 5));
menu.add(new Dish(7,09.99, "hello" , 5));
menu.add(new Dish(8,14.75, "hello" , 5));
menu.add(new Dish(9,100.01, "hello" , 5));
}
public static void main(String[] args) {
System.out.print("Insert port-number for the restaurantServer:");
PORT = sc.nextInt();
// listen on port 10023
try (ServerSocket server = new ServerSocket(PORT)) {
System.out.println("Chat-Server started on port: " + PORT);
while (true) {
customers.add(new Customer(server.accept()));
System.out.println("Customer geadded");
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
synchronized static boolean summmonCustomer(int table) {
boolean status = false;
status = tables[table] == 0;
return status;
}
synchronized static void removeCustomer(Customer customer) {
}
synchronized static List<Dish> returnDishList(){
return menu;
}
}
客户类别：
package Ue1SpeiseServer;
import java.io.*;
import java.net.Socket;
import java.nio.charset.Charset;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Customer extends Thread {
/**
* If this boolean is true the User is able to use extra functions
*/
private boolean restaurantEmployee;
/**
* The Customer socket
*/
private Socket socket;
/**
* The BufferedWriter
*/
private BufferedWriter out;
/**
* the nickname of the client
*/
private String table;
/**
* The Control Characters before the string
*/
private static final String STZ_DAVOR = new String(new byte[]{0x0b, 0x1b,
'[', '1', 'A', 0x1b, '7', 0x1b, '[', '1', 'L', '\r'});
/**
* The Control Characters after the string
*/
private static final String STZ_DANACH = new String(new byte[]{0x1b, '8',
0x1b, '[', '1', 'B'});
/**
* The bill for the customer
*/
private static Map<String, Double> bill = new HashMap<>();
/**
* Creates a ClientThread and starts it
*
* @param socket
*/
Customer(Socket socket) {
this.socket = socket;
start();
}
/**
* gets the socket of the customer
*
* @return
*/
public Socket getSocket() {
return socket;
}
/**
* @param message
* @throws IOException
*/
private void sendMessageToMe(String message) throws IOException {
out.write(STZ_DAVOR + message + STZ_DANACH);
out.flush();
}
/**
* runs the customerThread
*/
@Override
public void run() {
try (
BufferedReader in = new BufferedReader(new
InputStreamReader(socket.getInputStream(), Charset.forName("utf-8")));
BufferedWriter out = new BufferedWriter(new
OutputStreamWriter(socket.getOutputStream(), Charset.forName("utf-8")))
) {
this.out = out;
System.out.println("Connection accepted from" +
socket.getRemoteSocketAddress());
sendMessageToMe("Hello and welcome in the restaurant TrekNation
\r\n");
sendMessageToMe("If you want to leave type /leave \r\n");
sendMessageToMe("To get a list of our dishes type /list \r\n");
sendMessageToMe("If you have a complaint type /c *dish number*
*complaint* \r\n");
sendMessageToMe("Please insert your table number:");
while (true) {
table = in.readLine();
System.out.println(table.substring(table.length()-1));
int tableNumber =
Integer.parseInt(table.substring(table.length()-1));
if (RestaurantTrekNation.summmonCustomer(tableNumber)) {
sendMessageToMe("Your Table is ready prepare to order ");
break;
} else if (in.readLine().equals("") || in.readLine().contains("
")) {
sendMessageToMe("please us a valid table number");
} else {
sendMessageToMe("Table is full please choose another
table");
}
}
while (true) {
out.write( "Order>");
out.flush();
String input = in.readLine();
if (input == null) {
break;
} else {
if(input.equals("/list")){
synchronized (RestaurantTrekNation.customers) {
System.out.println("Avaibility Name Number");
List<Dish> dishes
=RestaurantTrekNation.returnDishList();
for (int i = 0; i < dishes.size(); i++) {
System.out.println(dishes.get(i));
}
}
}
}
}
} catch (IOException ie) {
RestaurantTrekNation.removeCustomer(this);
System.out.println("customer gone");
}
}
}
菜类：
package Ue1SpeiseServer;
public class Dish {
private static int catalogNumber;
private static Double costs;
private static String nameofDish;
public static int availabilityOfDish;
public Dish(int number, Double price, String name, int availability) {
catalogNumber = number;
costs = price;
nameofDish = name;
availabilityOfDish = availability;
}
public static int getCatalogNumber() {
return catalogNumber;
}
public static Double getCosts() {
return costs;
}
public static String getNameofDish() {
return nameofDish;
}
public static int getAvailabilityOfDish() {
return availabilityOfDish;
}
}
我能够使用Substring提取它，但是有更好的方法吗？
此致 卢卡斯