Java 中的 public、protected、package-private 和 private 有什么区别?
In Java, are there clear rules on when to use each of access modifiers, namely the default (package private), public, protected and private, while making class and interface and dealing with inheritance?
The official tutorial may be of some use to you.
| Class | Package | Subclass (same pkg) |
Subclass (diff pkg) |
World | |
|---|---|---|---|---|---|
public |
+ | + | + | + | + |
protected |
+ | + | + | + | |
| no modifier | + | + | + | ||
private |
+ |
+ : accessible
blank : not accessible