/**
* Skips over any whitespace characters, except for end-of-lines. After this method is called, the
* next input character is either an end-of-line, an end-of-file, or a non-whitespace character.
* This method never causes an error. (Ordinarly, end-of-file is not possible when reading from
* standard input.)
*/
public static void skipBlanks() {
char ch = lookChar();
while (ch != EOF && ch != '\n' && Character.isWhitespace(ch)) {
readChar();
ch = lookChar();
}
}
/**
* Skips over any whitespace characters, including for end-of-lines. After this method is called,
* the next input character is either an end-of-file or a non-whitespace character. This method
* never causes an error. (Ordinarly, end-of-file is not possible when reading from standard
* input.)
*/
private static void skipWhitespace() {
char ch = lookChar();
while (ch != EOF && Character.isWhitespace(ch)) {
readChar();
if (ch == '\n' && readingStandardInput && writingStandardOutput) {
// Removed for SP08 UIUC CS125 out.print("? ");
out.flush();
}
ch = lookChar();
}
}
private static void errorMessage(String message, String expecting) { // Report
// error
// on
// input.
if (readingStandardInput && writingStandardOutput) {
// inform user of error and force user to re-enter.
out.println();
out.print(" *** Error in input: " + message + "\n");
out.print(" *** Expecting: " + expecting + "\n");
out.print(" *** Discarding Input: ");
if (lookChar() == '\n') out.print("(end-of-line)\n\n");
else {
while (lookChar() != '\n')
// Discard and echo remaining chars
// on the current line of input.
out.print(readChar());
out.print("\n\n");
}
out.print("Please re-enter: ");
out.flush();
readChar(); // discard the end-of-line character
inputErrorCount++;
if (inputErrorCount >= 10)
throw new IllegalArgumentException(
"Too many input consecutive input errors on standard input.");
} else if (inputFileName != null)
throw new IllegalArgumentException(
"Error while reading from file \""
+ inputFileName
+ "\":\n"
+ message
+ "\nExpecting "
+ expecting);
else
throw new IllegalArgumentException(
"Error while reading from inptu stream:\n" + message + "\nExpecting " + expecting);
}
