Read Only Interfaces in Java
In Java, a read-only interface is an interface that only declares methods and does not contain any method implementations. These methods are meant to be implemented by a class that implements the interface. A read-only interface can be useful when you want to specify a set of methods that must be implemented by a class, but you don't want to provide any implementation for these methods.
Here is an example of a read-only interface in Java:
public interface ReadOnly {
int getValue();
}
This interface declares a single method getValue()
, which returns an int
value. A class that implements this interface must provide an implementation for this method.
Here is an example of a class that implements the ReadOnly
interface:
public class ReadOnlyImpl implements ReadOnly {
private int value;
public ReadOnlyImpl(int value) {
this.value = value;
}
@Override
public int getValue() {
return value;
}
}
The ReadOnlyImpl
class implements the getValue()
method of the ReadOnly
interface. This class can be used as follows:
ReadOnly ro = new ReadOnlyImpl(10);
int val = ro.getValue(); // val will be 10
In this example, the ReadOnly
interface serves as a contract that specifies that a class must implement the getValue()
method. The ReadOnlyImpl
class satisfies this contract by providing an implementation for the getValue()
method.