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在Client類中有一個while循環，我要求用戶進行一些計算。當我嘗試進行多個計算時，會出現此問題。它從服務器類中進行計算。保持Socket服務器的多種用途？
import java.io.*;
import java.net.*;
import java.util.*;
public class Client {
private static final int PORT = 1234;
public static void main(String[] arg) {
try {
Scanner userInputScanner = new Scanner(System.in);
Calculator c = new Calculator(0,0,"+");
CalculatorProtocol s = new CalculatorProtocol();
String testString = null;
String answer = null;
Socket socketConnection = new Socket(InetAddress.getLocalHost(),PORT);
ObjectOutputStream clientOutputStream = new
ObjectOutputStream(socketConnection.getOutputStream());
ObjectInputStream clientInputStream = new
ObjectInputStream(socketConnection.getInputStream());
do{
System.out.println("Give the 1st integer:");
testString = userInputScanner.next();
while (!s.isInteger(testString)) {
System.out.println("Wrong input data." + "Give the 1st integer:");
testString = userInputScanner.next();
}
c.setFirstNumber(Integer.parseInt(testString));
System.out.println("Give the 2nd integer:");
testString = userInputScanner.next();
while (!s.isInteger(testString)) {
System.out.println("Wrong input data." + "Give the 2nd integer:");
testString = userInputScanner.next();
}
c.setSecondNumber(Integer.parseInt(testString));
userInputScanner.nextLine(); // Gia na mi ginei lathos
System.out.println("Give the operator (+,-,*,/):");
testString = userInputScanner.nextLine();
while(!s.isOperator(testString)) {
System.out.println("Wrong input data."
+ "Give the operator(+,-,*,/):");
testString = userInputScanner.next();
}
c.setOperation(testString);
System.out.println("First integer:" +c.getFirstNumber());
System.out.println("Second integer:" +c.getSecondNumber());
System.out.println("Operator:"+c.getOperation());
clientOutputStream.writeObject(c);
c = (Calculator)clientInputStream.readObject();
System.out.println("Result="+c.getResult());
System.out.println("Want more?");
answer = userInputScanner.nextLine();
}while(s.wantMore(answer));
clientOutputStream.close();
clientInputStream.close();
}catch (Exception e) {System.out.println(e); }
}
}
服務器類
import java.io.*;
import java.net.*;
public class Server {
private static final int PORT = 1234;
public static void main(String[] arg) {
Calculator c = null;
CalculatorProtocol s = new CalculatorProtocol();
String answer = null;
try {
ServerSocket socketConnection = new ServerSocket(PORT);
System.out.println("Server Waiting");
while(true) {
Socket pipe = socketConnection.accept();
ObjectInputStream serverInputStream = new
ObjectInputStream(pipe.getInputStream());
ObjectOutputStream serverOutputStream = new
ObjectOutputStream(pipe.getOutputStream());
c = (Calculator)serverInputStream.readObject();
while (true) {
c.setResult(s.Calculate(c.getFirstNumber(), c.getSecondNumber()
, c.getOperation()));
serverOutputStream.writeObject(c);
}
}
} catch(Exception e) {System.out.println(e);
}
}
}
類用於協議
public class CalculatorProtocol {
private int a , b ;
private String d;
public static boolean isInteger(String str) {
if (str == null) {
return false;
}
int length = str.length();
if (length == 0) {
return false;
}
int i = 0;
if (str.charAt(0) == '-') {
if (length == 1) {
return false;
}
i = 1;
}
for (; i < length; i++) {
char c = str.charAt(i);
if (c <= '/' || c >= ':') {
return false;
}
}
return true;
}
public boolean isOperator(String op){
if(!(op.equals("+") || op.equals("-") || op.equals("*") || op.equals("/")))
return false;
else
d = op;
return true;
}
public int Calculate(int n1 , int n2 , String o) {
a = n1;
b = n2;
d = o;
int result = 0;
if (d.equals("+"))
result = a + b;
else if (d.equals("-"))
result = a - b;
else if (d.equals("*"))
result = a * b;
else
result = a/b;
return result;
}
public boolean wantMore(String m){
if (m.equals("Yes"))
return true;
else
return false;
}
}
import java.io.*;
import java.util.*;
public class Calculator implements Serializable {
private int num1,num2,result;
private String calc;
計算器類計算器對象。
Calculator (int a, int b, String p) {
num1 = a;
num2 = b;
calc = p;
result = 0;
}
public int getFirstNumber() {
return num1 ;
}
public int getSecondNumber() {
return num2 ;
}
public void setFirstNumber(int num) {
num1 = num;
}
public void setSecondNumber(int num) {
num2 = num;
}
public String getOperation() {
return calc ;
}
public void setOperation(String op) {
calc = op;
}
public void setResult(int d) {
result = d;
}
public int getResult() {
return result;
}
}