Sentence Statistics-Need Help

Question

I need to write a program that displays the Word count, sentence length, and average word length in a program, stopping input when the user presses enter. This is my code:
* @(#)sentence stats.java
* sentence stats application
* @author
* @version 1.00 2009/3/27
import java.util.Scanner;
public class sentencestats {
    public static void main(String[] args) {
    Scanner reading=new Scanner(System.in);
    while(input!=("")){
         System.out.print("Enter a sentence: ");
         String input=reading.nextLine();
    int wordCount=0;
    int sentenceLength=0;
    int beginPosition=0;
    int endPosition=input.indexOf('');
    while(endPosition != -1){
         if(endPosition>beginPosition){
              wordCount++;
              String word=input.substring(beginPosition,endPosition);
              sentenceLength+=word.length();
    beginPosition=endPosition+1;
    endPosition=input.indexOf('',beginPosition);
    if(beginPosition<input.length()){
         wordCount++;
         String word=input.substring(beginPosition,input.length());
         sentenceLength+=word.length();
    if(wordCount>0){
         System.out.println("Word count: "+wordCount);
         System.out.println("Sentece length: "+sentenceLength);
         System.out.println("Average word length: "+sentenceLength/wordCount);
}But i get the error messages:
empty character literal
unclosed character literal
empty character literal
unclosed character literal
not a statement
';' expected

Answer 1

On quick glance, you're
1) testing the String, input, before you've declared it.
2) trying to compare Strings with == or !=. Don't do this. Use equals or equalsIgnoreCase, or compareTo or isEmpty() as appropriate