执行结果截图：

 

 代码：

public class TernaryOperator {
    public static void main(String[] args) {
        int a = 10;
        int b = 20;

        a+=b;   //a = a+b
        a-=b;   //a = a-b

        System.out.println(a);
        //字符串连接符
        System.out.println(a+b);
        System.out.println(""+a+b);  // 如果前面是字符串，后面的a和b都会自动转换为字符串，不会计算
        System.out.println(a+b+"");  // 如果后面跟字符串，前面的a和b不会自动转换字符串，会计算

        boolean x = true;
        String y = "ok";
        String z = "not ok";

        //?:是三目运算符，如果x==true，则结果为y，否则结果为z
        System.out.println(x?y:z);    
        System.out.println(!x?y:z);

        int score = 80;
        String type = score < 60 ? "failing grade":"passing grade";
        System.out.println(type);

        score = 50;
        type = score < 60 ? "failing grade":"passing grade";
        System.out.println(type);


    }
}