Example
public
abstract
class
A{
public
abstract
void
method_1();
public
void
method_2()
{
}
}
public
abstract
class
B
extends
A{
public
abstract
void
method_1();
public
abstract
void
method_2();
}
Solution
In the example method_2 has a definition in parent class A. But in the subclass B it has been declared as abstract. This should be avoided.