/** TestInterpretInput operation by reading one of each value
** supported by its public interface either from the console
** or a file indicated on the command line.
**/
import java.io.FileNotFoundException;
import java.io.EOFException;
import java.io.IOException;
public class TestInputInterpreter {
InputInterpreter inputSource = null;
/** Create an InputInterpreter associated with either the
** console or a file whose name is given in the srgument array.
**/
private void setUpInput(String args[]) throws FileNotFoundException {
if (args.length == 0) {
// Read and interpret console input
inputSource = new InputInterpreter();
}
else {
// Read and interpret input from file indicated in args
inputSource = new InputInterpreter(args[0]);
}
}
/** Read and interpret the contents of the input source.
**/
private void readInput() {
boolean doPrompts = inputSource.isConsole();
try {
while (true) {
if (doPrompts)
System.out.println("Enter a string, e.g., your name");
// Declare a String and then ask inputSource to read a String
// and assign it to the String object you've declared
if (doPrompts)
System.out.println("Enter an int, e.g., your age");
// Declare an int and then ask inputSource to read an int
// value and assign it to the int variable you've declared
if (doPrompts)
System.out.println("Enter digits for a double, e.g., taxes paid");
// Declare a double and then ask inputSource to read a
// double value and assign it to the double variable
// you've declared
// Report the String, int and double values you've read in
}
}
catch (EOFException eof) {
System.out.println("caught end of file");
}
}
// Read records from the indicated file
public int readRecords( String filename ) {
int numRecords = 0;
int recordsRead = 0;
try {
// Read and interpret input from file indicated in filename
inputSource = new InputInterpreter(filename);
// Assume the input file consists of an initial line that has
// the number of records, followed by the records themselves
numRecords = inputSource.readIntValue();
// Now read that many records. Each record consists of a
// String, an int value, and a double value, each on
// separate lines. So the file contains
// string
// int
// double
// string
// int
// double
// ...
String stringVal;
int intVal;
double dblVal;
for (recordsRead = 0; recordsRead < numRecords; recordsRead++ ) {
stringVal = inputSource.readString();
intVal = inputSource.readIntValue();
dblVal = inputSource.readDoubleValue();
// do something useful with the three input items read,
// like print them, make a new object with them ...
}
}
catch (FileNotFoundException e) {
// whoops
return 0; // read 0 records
}
catch (EOFException e) {
// got to end of file earlier than expected
System.err.println("End of file after " + recordsRead + " records");
return recordsRead;
}
catch (IOException e) {
// some other unexpected problem; have it report itself
System.err.println(e);
return 0;
}
return numRecords;
}
public static void main( String[] args) {
TestInputInterpreter tester = new TestInputInterpreter();
try {
// One of the constructors can throw a FileNotFound
// exception; thus the need to enclose the following in a
// try block.
tester.setUpInput(args);
tester.readInput();
}
catch (FileNotFoundException e) {
System.out.println(e);
}
}
}
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