I have an abstract library package ‘baseplugin’. It includes an abstract BaseClient class that has abstract connect() method that must not be public.
//baseplugin/BaseClient.scala
package baseplugin
class BaseClient {
protected def connect(): Unit
}
I also have a implementation package, myplugin that is outside the baseplugin package hierarchy. It includes MyClient that extends BaseClient and implements its connect() method. Again, the connect() method must not be public
//myplugin/MyClient.scala
package myplugin
import baseplugin.BaseClient
class MyClient extends BaseClient {
override protected def connect(): Unit = {
// implementation logic here.
}
}
I want to add a strategy class in both packages that connects to NE is different ways.
// baseplugin/ReconnectStrategy.scala
package baseplugin
class BaseReconnectStrategy(client: BaseClient) {
def reconnect() {
client.connect()
// additional base logic here.
}
}
//myplugin/CustomReconnectStrategy.scala
package myplugin
class CustomReconnectStrategy(client: MyClient) {
def reconnect() {
// custom validation here.
client.connect()
// custom logic here.
}
}
However the protected access modifier is not allowing me to access client.connect() in BaseReconnectStrategy class.
If I set it to protected[baseplugin] or private[baseplugin] then the Scala compiler is asking me to add “override protected[baseplugin]” to the overridden connect() method in MyClient.
weaker access privileges in overriding
protected[package baseplugin] def connect(): Unit (defined in class BaseClient)
override should at least be protected[baseplugin]
override protected def connect(): Unit = {
If I add it to the overriding method then the compiler throws an exception that “baseplugin” is not in scope:
baseplugin is not an enclosing class
override protected[baseplugin ] def connect(): Unit = {
What is the scala idomatic way to implement Java protected access modifier when I want both of the following features:
- Access the BaseClient.connect() method within same package in BaseReconnectStrategy class
- Access the BaseClient.connect() within the subclass MyClient that is in a package outside the baseplugin hierarchy.
I’m using scala-2.13.10 in my package and unfortunately I cannot upgrade it. Can anyone please share your inputs on how I can achieve above requirement?
