An abstract class have abstract modifier in its declaration. An abstract class can contain  instance variable, methods that can be concrete methods and abstract methods. An abstract class may not have any abstract method, that does not mean that it is not an abstract class.

Example :

public abstarct AbstractClass{
// instance variable
int a;
int b;
//instance methods
public int getValue(){}
public void setValue(int){}
//abstract method
public int getMaxValue();
}