The methods in a class diagram represent the actions that the class can perform. For instance, a method with an add(x,y) method could add two integers while a getName() could return a variable containing the name of a person.
No. never. An instance method cannot replace a class method because: Instance Methods - are normal methods that are linked to a class object instance Class Methods - are static methods that are not linked to any class object. These methods are not interchangeable and will create too many issues if we try to use one in place of the other.
Instance methods can be called by the object of a Class whereas static method are called by the Class. When objects of a Class are created, they have their own copy of instance methods and variables, stored in different memory locations. Static Methods and variables are shared among all the objects of the Class, stored in one fixed location in memory.Static methods cannotaccess instance variables or instance methods directly-they must use an object reference. Also, class methods cannot use the this keyword as there is no instance for this to refer to.
A private member of a class can only be accessed by methods of that class. A protected member of a class can only be accessed by methods of that class and by methods of a derived class of that class.
It is a static class; meaning that all the methods can be accessed directly from the class name, without instantiating an object.It is a static class; meaning that all the methods can be accessed directly from the class name, without instantiating an object.It is a static class; meaning that all the methods can be accessed directly from the class name, without instantiating an object.It is a static class; meaning that all the methods can be accessed directly from the class name, without instantiating an object.
It depends on how the class is declared.If the class is a normal class - Then the compiler will complain. All the methods in an interface must be implemented by the class to successfully compile the classIf the class is declared as abstract - Then the compiler will ignore the fact that a few methods are not implemented
class diagram for payroll system
No. never. An instance method cannot replace a class method because: Instance Methods - are normal methods that are linked to a class object instance Class Methods - are static methods that are not linked to any class object. These methods are not interchangeable and will create too many issues if we try to use one in place of the other.
Class diagram represent generalized view of system while object diagram represent view of a system at a particular instant.
Static methods or class methods are usually used when you want functionality to be executed without creating an instance of the class where that piece of code resides.
one is a diagram like a chart or graph, and one is a design like a blue print
A private member of a class can only be accessed by methods of that class. A protected member of a class can only be accessed by methods of that class and by methods of a derived class of that class.
Instance methods can be called by the object of a Class whereas static method are called by the Class. When objects of a Class are created, they have their own copy of instance methods and variables, stored in different memory locations. Static Methods and variables are shared among all the objects of the Class, stored in one fixed location in memory.Static methods cannotaccess instance variables or instance methods directly-they must use an object reference. Also, class methods cannot use the this keyword as there is no instance for this to refer to.
---- A class diagram is useful, because if you didn't know what something looked like, then you would be pretty dumb
Class diagram
It is a static class; meaning that all the methods can be accessed directly from the class name, without instantiating an object.It is a static class; meaning that all the methods can be accessed directly from the class name, without instantiating an object.It is a static class; meaning that all the methods can be accessed directly from the class name, without instantiating an object.It is a static class; meaning that all the methods can be accessed directly from the class name, without instantiating an object.
Factory methods are merely a convention whereby static methods in a class return an instance of that class. The InetAddress class has no visible constructors. In InetAddress the 3 factory methods getLocalHost, getByName, getAllByName can be used to create instances of InetAddress.
It depends on how the class is declared.If the class is a normal class - Then the compiler will complain. All the methods in an interface must be implemented by the class to successfully compile the classIf the class is declared as abstract - Then the compiler will ignore the fact that a few methods are not implemented