java - 如何比较字符串

Question

我试图让用户按下数字，然后他们输入他们想要查看的可用选项的字符串。到目前为止一切正常，除了当用户输入字符串时它没有给出首选输出。*显示电子邮件而不是颜色、用户 ID 等。这是我的代码。再次感谢!

public static void printStuff(Record[] objects) {
   Scanner in = new Scanner(System.in);
   System.out.println("Enter the number and record name you would like to see");
   int x = in.nextInt();
   String bean = in.next();


        if (x == 1 || x == 2 || x == 3 || x == 4 || x == 5 && bean.equals("email")) {
            System.out.println(objects[x].getEmail());
        }
       else if (x == 1 || x == 2 || x == 3 || x == 4 || x == 5 && bean.equals("name")) {
            System.out.println(objects[x].getfirstName());
        }

       else if (x == 1 || x == 2 || x == 3 || x == 4 || x == 5 && bean.matches("last name")) {
            System.out.println(objects[x].getlastName());
        }

       else if (x == 1 || x == 2 || x == 3 || x == 4 || x == 5 && bean.matches("balance")) {
            System.out.println(objects[x].getBalance());
        }

       else if (x == 1 || x == 2 || x == 3 || x == 4 || x == 5 && bean.matches("color")) {
            System.out.println(objects[x].getColor());
        }

       else if (x == 1 || x == 2 || x == 3 || x == 4 || x == 5 && bean.matches("idnumber")) {
            System.out.println(objects[x].getnumID());
        }
 }

Answer 1

在所有的 if 条件下，&&优先级高于 || ，因此您必须将条件更改为:

(x == 1 || x == 2 || x == 3 || x == 4 || x == 5) && bean.equals("email") .

这对应你想要的逻辑，如果x是 1 到 5 中的某个值 AND bean 等于 "email" .但是，请查看比较运算符，因为您可以将其简化为:

(1 <= x && x <= 5) && bean.equals("email") .