Answers to Self-Review Questions - Java Software Solutions: Foundations of Program Design - page 764

7.3 Static Class Members
SR 7.6 Memory space for an instance variable is created for each object that is

instantiated from a class. A static variable is shared among all objects
of a class.

SR 7.7 Assuming you decide to use the identifier totalBalance , the declaration is:

private static int totalBalance = 0;

SR 7.8 Assuming that the minimum required is 100 and you decide to use the

identifier MIN_BALANCE , the declaration is:
public static final int MIN_BALANCE = 100;

SR 7.9 The main method of any program is static, and can refer only to static

or local variables. Therefore, a main method could not refer to instance
variables declared at the class level.

7.4 Class Relationships
SR 7.10

A dependency relationship between two classes occurs when one class
relies on the functionality of the other. It is often referred to as a “uses”
relationship.

SR 7.11 A method executed through an object might take as a parameter

another object created from the same class. For example, the concat
method of the String class is executed through one String object and
takes another String object as a parameter.

SR 7.12 An aggregate object is an object that has other objects as instance data.

That is, an aggregate object is one that is made up of other objects.

SR 7.13 The this reference always refers to the currently executing object. A

non-static method of a class is written generically for all objects of the
class, but it is invoked through a particular object. The this reference,
therefore, refers to the object through which that method is currently
being executed.

7.5 Interfaces
SR 7.14 A class can be instantiated; an interface cannot. An interface contains a

set of abstract methods for which a class provides the implementation.

SR 7.15

public interface Nameable
{

public void setName (String name);
public String getName();

}