你不能从 void 方法返回值，这就是 void 方法的目的，它会做它所做的事情并完成.

• You can't return a value from a void method, that's the purpose of void method, it does what it does and finish.

  Java 是按值传递的，当你传递一个引用类型时，它的地址不会改变，但它的属性会受到改变的影响.

  Java is pass-by-value, when you pass a reference type, its address won't be changed but its attributes will be effected by the change.