转自:

http://www.java265.com/JavaCourse/202203/2493.html

运算符简介:

 运算符用于执行程序代码运算，会针对一个以上操作数项目来进行运算<br />

例：88+99，其操作数是88和99，而运算符则是“+”。在vb2005中运算符大致可以分为5种类型：算术运算符、连接运算符、关系运算符、赋值运算符和逻辑运算符。

下文笔者讲述java中冒号运算符的功能简介说明,如下所示:

冒号运算符的功能:
    1.跳转
	2.三元表达式
	3.迭代循环
	4.断言
	5.switch
	6.方法(jdk8)

例

1 跳出标签
label: for (int i = 0; i < x; i++) {
    for (int j = 0; j < i; j++) {
        //业务代码
    }
}  

2 三元条件
int a = (b < 4)? 7: 8; // if b < 4, set a to 7, else set a to 8

3 每个循环
String[] ss = {"hi", "there"}
for (String s: ss) {
    print(s);  
}

4 断言
int a = factorial(b);
assert a >= 0: "factorial may not be less than 0"; // throws an AssertionError with the message if the condition evaluates to false

5 switch
switch (type) {
    case WHITESPACE:
    case RETURN:
        break;
    case NUMBER:
        print("got number: " + value);
        break;
    default:
        print("syntax error");
}
6 方法参考
class User {
   public static int compareByAge(User a, User b) {
       return a.birthday.compareTo(b.birthday);
   }}
}

Arrays.sort(users, User::compareByAge);