The official tutorial may be of some use to you.

______________________________________________________________
|           │ Class │ Package │ Subclass │ Subclass │ World  |
|           │       │         │(same pkg)│(diff pkg)│        |
|───────────┼───────┼─────────┼──────────┼──────────┼────────|
|public     │   +   │    +    │    +     │     +    │   +    | 
|───────────┼───────┼─────────┼──────────┼──────────┼────────|
|protected  │   +   │    +    │    +     │     +    │        | 
|───────────┼───────┼─────────┼──────────┼──────────┼────────|
|no modifier│   +   │    +    │    +     │          │        | 
|───────────┼───────┼─────────┼──────────┼──────────┼────────|
|private    │   +   │         │          │          │        |
|___________|_______|_________|__________|__________|________|
 + : accessible         blank : not accessible