Data and Expressions - Java Software Solutions: Foundations of Program Design - page 87

SR 2.34 Assuming result is a float variable that contains the value 27.32 and
value is an int variable that contains the value 15, what are the val-
ues of each of the variables after the following assignment statement is
executed? Explain.

value = ( int ) result;

SR 2.35 Given the following declarations, what result is stored by each of the
following assignment statements.

int iResult, num1 = 17, num2 = 5;
double fResult, val1 = 12.0, val2 = 2.34;

a. iResult = num1 / num2;
b. fResult = num1 / num2;
c. fResult = val1 / num2;
d. fResult = ( double ) num1 / num2;
e. iResult = ( int ) val1 / num2;

2.6 Interactive Programs

It is often useful to design a program to read data from the user interactively dur-
ing execution. That way, new results can be computed each time the program is
run, depending on the data that is entered.

The Scanner Class
The Scanner class, which is part of the standard Java class library,
provides convenient methods for reading input values of various
types. The input could come from various sources, including data
typed interactively by the user or data stored in a file. The Scanner
class can also be used to parse a character string into separate pieces.
Figure 2.7 lists some of the methods provided by the Scanner class.
We must first create a Scanner object in order to invoke its methods. Objects
in Java are created using the new operator. The following declaration creates a
Scanner object that reads input from the keyboard:

KEY CONCEPT
The Scanner class provides methods
for reading input of various types
from various sources.

Scanner scan = new Scanner (System.in);

This declaration creates a variable called scan that represents a Scanner object.
The object itself is created by the new operator and a call to a special method