java - 为最终变量分配函数返回类型

Question

在java中，我尝试用函数返回值分配最终变量。但我得到了编译错误。谁能帮我看看是什么原因导致了这里的错误？

代码是这样的:

public class A{
  private static final set<String> set1 = getSet();
  private Static Set<String> getSet(){
     Vector<String> vector1 = getVector();//some function which return the Vector of type String
     if(vector1!=null){
           set1=new HashSet<String>(vactor1);
     }
     else{
           set1= new HashSet<String>();
     }
  }
}

Answer 1

private static final set<String> set1 = getSet();

set1 是最终，这意味着它无法更改。

但是，

set1=new HashSet<String>(vactor1);

和

set1= new HashSet<String>();

正在努力改变它。请参阅JLS 4.12.4. final Variables :

A variable can be declared final. A final variable may only be assigned to once. Declaring a variable final can serve as useful documentation that its value will not change and can help avoid programming errors.

It is a compile-time error if a final variable is assigned to unless it is definitely unassigned (§16) immediately prior to the assignment.

我不知道是否是拼写错误，但是 static 应该全部小写，而不是 Static。