StrTokDemo4.java

package chapter3;
import java.util.StringTokenizer;

public class StrTokDemo4 {
	public final static int MAXFIELDS = 5;
	public final static String DELIM = "|";
	
	/** Processes one String, returns it as an array of Strings */
	public static String[] process(String line) {
	String[] results = new String[MAXFIELDS];
	// Unless you ask StringTokenizer to give you the tokens,
	// it silently discards multiple null tokens.
	StringTokenizer st = new StringTokenizer(line, DELIM, true);
	int i = 0;
	// stuff each token into the current slot in the array.
	while (st.hasMoreTokens()) {
	String s = st.nextToken();
	if (s.equals(DELIM)) {
	if (i++>=MAXFIELDS)
	// This is messy: See StrTokDemo4b which uses a List to allow any number of fields.

		throw new IllegalArgumentException("Input line " +
				line + " has too many fields");
				continue;
				}
				results[i] = s;
				}
				return results;
				}
				public static void printResults(String input, String[] outputs) {
				System.out.println("Input: " + input);
				for (String s : outputs)
				System.out.println("Output " + s + " was: " + s);
				}
				// Should be a JUnit test but is referred to in the book text,
				// so I can't move it to "tests" until the next edit.
				public static void main(String[] args) {
				printResults("A|B|C|D", process("A|B|C|D"));
				printResults("A||C|D", process("A||C|D"));
				printResults("A|||D|E", process("A|||D|E"));
				}
				}