ARRAYS - Java Programming: From Problem Analysis to Program Design - page 611

It now follows that the method main needs (at least) the following variables:

int lineCount = 0; //variable to store the line count

int [] letterCount = new int[26]; //array to store the letter
//count

int next; //variable to read a character

FileReader inputStream = new FileReader("text.txt");

PrintWriter outfile = new PrintWriter("textCh.out");
(Note that the method read throws an IOException when something goes wrong.
At this point, we will ignore this exception by throwing it in the program. Excep-
tions are covered in detail in Chapter 11.)
In this declaration, letterCount[0] stores the A count, letterCount[1] stores the
B count, and so on. Clearly, the variable lineCount and the array letterCount
must be initialized to 0 .
The algorithm for the program is:
1. Declare and initialize the variables.
2. Create objects to open the input and output files.
3. While there is more data in the input file:
a. For each character in a line:
i. Read and write the character.
ii. Increment the appropriate letter count.
b. Increment the line count.
4. Output the line count and letter counts.
5. Close the files.
To simplify the method main , we divide it into three methods:
1. Method copyText
2. Method chCount
3. Method writeTotal
The following sections describe each method in detail. Then, with the help of these
methods, we describe the algorithm for the method main .

9

This method reads a line and outputs the line. Whenever a nonblank character is
found, it calls the method chCount to update the letter count. Clearly, this method
has four parameters: an input stream object, an output stream object, a variable to
read the character, and the array to update the letter count.

copyText