java简单计算器的程序

‘+’的结果错了，别的没错，不知道什么问题。

class SimpleCal2 {
private int operand1,operand2;
private char operator;

SimpleCal2(){}

SimpleCal2(int operand1,char operator,int operand2){
this.operand1=operand1;

this.operator=operator;
this.operand2=operand2;
}

private int cal() throws ArithmeticException,Exception{
int result=Integer.MIN_VALUE;
if(operator=='+')
result=operand1+operand2;
else if(operator=='-'){
result=operand1-operand2;
}
else if(operator=='*'){
result=operand1*operand2;
}
else if(operator=='/'){
result=operand1/operand2;
}
else {
throw new Exception("输入的运算符错误!");
}
return result;
}

public void showResult() throws ArithmeticException,Exception{
System.out.println("运算结果："+operand1+operator+operand2+"="+cal());
}

public static void main(String[] args){
int p1,p2;
try{
p1=Integer.parseInt(args[0]);
char op=args[1].charAt(0);
p2=Integer.parseInt(args[2]);
SimpleCal2 exp=new SimpleCal2(p1,op,p2);
exp.showResult();
}
catch(NumberFormatException e1){
System.out.println("输入的运算数不是整数！");
}
catch(ArrayIndexOutOfBoundsException e2){
System.out.println("输入的运算式不完整!");
}
catch(ArithmeticException e3){
System.out.println("除数为0，不能进行除法运算！");
}
catch(Exception e4){
e4.printStackTrace();
}
}
}

我做了测试你的程序没有问题.

class SimpleCal2 {
private int operand1, operand2;
private char operator;

SimpleCal2() {
}

SimpleCal2(int operand1, char operator, int operand2) {
this.operand1 = operand1;

this.operator = operator;
this.operand2 = operand2;
}

private int cal() throws ArithmeticException, Exception {
int result = Integer.MIN_VALUE;
if (operator == '+')
result = operand1 + operand2;
else if (operator == '-') {
result = operand1 - operand2;
} else if (operator == '*') {
result = operand1 * operand2;
} else if (operator == '/') {
result = operand1 / operand2;
} else {
throw new Exception("输入的运算符错误!");
}
return result;
}

public void showResult() throws ArithmeticException, Exception {
System.out.println("运算结果：" + operand1 + operator + operand2 + "="
+ cal());
}

public static void main(String[] args) {
int p1, p2;char op;
try {
//p1 = Integer.parseInt(args[0]);
p1=3;
//char op = args[1].charAt(0);
op='+';
//p2 = Integer.parseInt(args[2]);
p2=2;
SimpleCal2 exp = new SimpleCal2(p1, op, p2);
exp.showResult();
} catch (NumberFormatException e1) {
System.out.println("输入的运算数不是整数！");
} catch (ArrayIndexOutOfBoundsException e2) {
System.out.println("输入的运算式不完整!");
} catch (ArithmeticException e3) {
System.out.println("除数为0，不能进行除法运算！");
} catch (Exception e4) {
e4.printStackTrace();
}
}
}

运算结果：3+2=5

你的程序没有错.

错误时什么?计算结果错了，还是输出的信息有误