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printf only printing while passing the last index value of an array of class object

I created a class object array and but now when I try to print it using printf method then it doesn't print those values, I tried checking if the values are correct using println and it works fine with it. One more thing which was weird is that when I pass the end index of the array then it prints them. for example class object array is of size 20 (0-19), when I pass 19th index to the method which prints it then it is working but for 0-18 it is not working.
package com.insurance.company;
import java.util.List;
/**
*
* #author Lenovo
*/
public class InsuranceCompany {
private String companyName;
private String telephone;
private String webAddress;
private double brokerPercentage;
private String description;
private List<String> insuranceTypes;
public InsuranceCompany(){}
public InsuranceCompany(String companyName, String telephone, String webAddress, double brokerPercentage, String description, List<String> insuranceTypes) {
this.companyName = companyName;
this.telephone = telephone;
this.webAddress = webAddress;
this.brokerPercentage = brokerPercentage;
this.description = description;
this.insuranceTypes = insuranceTypes;
}
#Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append(companyName);
sb.append(" " + telephone);
sb.append(" " + webAddress);
for(int i = 0; i < insuranceTypes.size(); i++){
sb.append(" " + insuranceTypes.get(i));
}
sb.append(" " + brokerPercentage);
sb.append(" " + description);
return sb.toString();
}
public String getCompanyName() {
return companyName;
}
public String getTelephone() {
return telephone;
}
public String getWebAddress() {
return webAddress;
}
public double getBrokerPercentage() {
return brokerPercentage;
}
public String getDescription() {
return description;
}
public List<String> getInsuranceTypes() {
return insuranceTypes;
}
}
package com.insurance.company;
import java.io.File;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class InsurancePortal {
//function to load data from file
private static String loadDataFromFile(String path)throws Exception{
String data;
data = new String(Files.readAllBytes(Paths.get(path)));
return data;
}
//function to list all insurance companies
private static void listInuranceCompanies(InsuranceCompany[] company){
System.out.println("------------------------------------------------------------------------------------------------------------------------------------------------");
System.out.printf("| %3s | %-20s | %-111s |%n", "ID", "Company Name", "Cover Types");
//System.out.flush();
System.out.println("------------------------------------------------------------------------------------------------------------------------------------------------");
for(int j = 0; j < company.length; j++){
System.out.printf("| %3d | %-20s |", j+1, company[j].getCompanyName());
for(int i = 0; i < 7; i++){
if(i < company[j].getInsuranceTypes().size()){
System.out.printf(" %15S", company[j].getInsuranceTypes().get(i));
}else{
System.out.printf(" %15s", " ");
}
}
System.out.print(" |\n");
System.out.println("------------------------------------------------------------------------------------------------------------------------------------------------");
}
}
//function to search cover
public static void listSingleCompanyDetails(InsuranceCompany selectedCompany){
System.out.println(selectedCompany.getCompanyName()+"\n--------------------------------------------------");
//System.out.flush();
System.out.printf("| %-18S | %-28S |%n", selectedCompany.getCompanyName(), selectedCompany.getDescription());
//System.out.flush();
System.out.println("--------------------------------------------------");
System.out.println("--------------------------------------------------");
System.out.println("--------------------------------------------------");
System.out.println("--------------------------------------------------");
System.out.println("--------------------------------------------------");
}
public static void main(String arge[]) throws Exception{
String dataFile = System.getProperty("user.dir") + File.separator + "insurance-data.txt";
String[] data = loadDataFromFile(dataFile).split("\n");
/*for(String str: data){
System.out.println(str);
}*/
int rows = data.length;
InsuranceCompany[] company = new InsuranceCompany[rows];
//Initialising objects for every row of data in the file
for(int j = 0; j < rows; j++){
String row = data[j];
//System.out.println(row);
String companyName, telephone, webAddress, description;
double brokerPercentage;
List<String> insuranceTypes = new ArrayList<>();
//Splitting for Company Name
String[] splittedArray = row.split(":", 2);
companyName = splittedArray[0];
row = splittedArray[1];
//Splitting for telephone
splittedArray = row.split(":", 2);
telephone = splittedArray[0];
row = splittedArray[1];
//splitting for web address
splittedArray = row.split(":", 2);
webAddress = splittedArray[0];
row = splittedArray[1];
//splitiing for insurance types
splittedArray = row.split(":", 2);
String[] insuranceTypeList = splittedArray[0].split(",");
for(String str : insuranceTypeList){
insuranceTypes.add(str);
}
row = splittedArray[1];
//splitting for broker percentage
splittedArray = row.split(":", 2);
brokerPercentage = Double.parseDouble(splittedArray[0]);
row = splittedArray[1];
//splitting for description
splittedArray = row.split(":", 2);
description = splittedArray[0];
//System.out.println(companyName+ " " + telephone + " " +webAddress + " " + brokerPercentage + " " + description);
/*for(int i = 0; i < insuranceTypes.size(); i++){
System.out.print(insuranceTypes.get(i)+" ");
}*/
company[j] = new InsuranceCompany(companyName, telephone, webAddress, brokerPercentage, description, insuranceTypes);
//System.out.println(company[j].getCompanyName());
}
boolean run = true;
while(run){
int choice;
Scanner sc = new Scanner(System.in);
System.out.print("\nList insurance companies.......1\n"
+ "Select insurance company.......2\n"
+ "Search cover...................3\n"
+ "Exit...........................0\n"
+ "\nEnter choice:> ");
choice = sc.nextInt();
switch(choice){
case 1 :
listInuranceCompanies(company);
break;
case 2 :
System.out.print("Enter company ID from list [1 - "+(company.length)+"] :> ");
int selectedCompany;
selectedCompany = sc.nextInt();
listSingleCompanyDetails(company[selectedCompany-1]);
break;
case 0 :
System.exit(0);
break;
default: System.out.println("Invalid choice!, please try again.");
}
}
}
}

Passing a parameter to another function

I wrote a code for hangman, and i want to pass the randomly guessed word(randomly guessed from a text file), to be passed to a function hangman() where i can get the length of the word. a random word will be guessed from the getRandomWord(String path) function and I have passed value obtained to function() But cannot seem to pass the and get the result.
public class Main {
public static void main(String[] args) throws IOException {
Main ma = new Main();
String stm= null;
loadWords();
//hangman(w);
function();
}
public static String[] loadWords() {
System.out.println("Loading words from file :");
try {
File myObj = new File("C:\\Users\\Admin\\Documents\\NetBeansProjects\\Main\\words.txt");
Scanner myReader = new Scanner(myObj);
while (myReader.hasNext()) {
String data = myReader.nextLine().toLowerCase();
String[] spl = data.split(" ");
System.out.println(spl.length + " words loaded");
return spl;
}
myReader.close();
} catch (FileNotFoundException e) {
System.out.println("An error occurred.");
e.printStackTrace();
}
return null;
// TODO: Fill in your code here
}
public static String getRandomWord(String path) throws IOException {
List<String> words = new ArrayList<String>();
try (BufferedReader reader = new BufferedReader(new FileReader(path))) {
String line;
while ((line = reader.readLine()) != null) {
String[] wordline = line.split("\\s+");
for (String word : wordline) {
words.add(word);
}
}
}
Random rand = new Random();
return words.get(rand.nextInt(words.size()));
}
public static List< String> getRemainingLetters(ArrayList< String> lettersGuessed) {
String alpha = "abcdefghijklmnopqrstuvwxyz";
String[] alpha1 = alpha.split("");
ArrayList< String> alpha2 = new ArrayList<>(Arrays.asList(alpha1));
for (int i = 0; i < lettersGuessed.size(); i++) {
for (int j = 0; j < alpha2.size(); j++) {
if (alpha2.get(j).equals(lettersGuessed.get(i))) {
alpha2.remove(j);
break;
}
}
}
return alpha2;
}
public static void function() throws IOException {
int numGuesses = 5;
String w = getRandomWord("C:\\Users\\Admin\\Documents\\NetBeansProjects\\Main\\words.txt");
String[] word = w.split("");
ArrayList< String> wList = new ArrayList<>(Arrays.asList(word));
ArrayList< String> wAnswer = new ArrayList< String>(wList.size());
for (int i = 0; i < wList.size(); i++) {
wAnswer.add("_ ");
}
int left = wList.size();
Scanner scanner = new Scanner(System.in);
boolean notDone = true;
ArrayList< String> lettersGuessed = new ArrayList< String>();
while (notDone) {
System.out.println();
String sOut = "";
List< String> lettersLeft = getRemainingLetters(lettersGuessed);
for (String s : lettersLeft) {
sOut += s + " ";
}
System.out.println("Letters Left: " + sOut);
sOut = "";
for (int i = 0; i < wList.size(); i++) {
sOut += wAnswer.get(i);
}
System.out.println(sOut + " Guesses left:" + numGuesses);
System.out.print("Enter a letter(* exit): ");
String sIn = scanner.next();
numGuesses--;
if (sIn.equals("*")) {
break;
}
lettersGuessed.add(sIn);
for (int i = 0; i < wList.size(); i++) {
if (sIn.equals(wList.get(i))) {
wAnswer.set(i, sIn);
left--;
}
}
if (left == 0) {
System.out.println("Congradulations you guessed it!");
break;
}
if (numGuesses == 0) {
StringBuilder sb = new StringBuilder();
for (String string : wList) {
sb.append(string);
}
String stm = sb.toString();
System.out.println("Sorry you ran out of guesses, the word was: " + stm);
break;
}
}
}
public static void hangman(String word) {
System.out.println("Welcome to Hangman Ultimate Edition");
System.out.println("I am thinking of a word that is " + word.length() + " letters long");
System.out.println("-------------");
}
}

Problems in your code:
Not passing the random word to the methods, hangman and function.
Instead of re-using the random word obtained from the method, getRandomWord in main, you have called getRandomWord again in the method, hangman which will give you a different random word causing incosistency.
Given below is the corrected program with a sample run:
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Random;
import java.util.Scanner;
public class Main {
public static void main(String[] args) throws IOException {
String word = getRandomWord("C:\\Users\\Admin\\Documents\\NetBeansProjects\\Main\\words.txt");
hangman(word);
function(word);
}
public static String getRandomWord(String path) throws IOException {
List<String> words = new ArrayList<String>();
try (BufferedReader reader = new BufferedReader(new FileReader(path))) {
String line;
while ((line = reader.readLine()) != null) {
String[] wordline = line.split("\\s+");
for (String word : wordline) {
words.add(word);
}
}
}
Random rand = new Random();
return words.get(rand.nextInt(words.size()));
}
public static List<String> getRemainingLetters(ArrayList<String> lettersGuessed) {
String alpha = "abcdefghijklmnopqrstuvwxyz";
String[] alpha1 = alpha.split("");
ArrayList<String> alpha2 = new ArrayList<>(Arrays.asList(alpha1));
for (int i = 0; i < lettersGuessed.size(); i++) {
for (int j = 0; j < alpha2.size(); j++) {
if (alpha2.get(j).equals(lettersGuessed.get(i))) {
alpha2.remove(j);
break;
}
}
}
return alpha2;
}
public static void function(String w) throws IOException {
// The available number of guesses = length of the random word
int numGuesses = w.length();
// Split the random word into letters
String[] word = w.split("");
ArrayList<String> wList = new ArrayList<>(Arrays.asList(word));
ArrayList<String> wAnswer = new ArrayList<String>(wList.size());
for (int i = 0; i < wList.size(); i++) {
wAnswer.add("_ ");
}
int left = wList.size();
Scanner scanner = new Scanner(System.in);
boolean notDone = true;
ArrayList<String> lettersGuessed = new ArrayList<String>();
while (notDone) {
System.out.println();
String sOut = "";
List<String> lettersLeft = getRemainingLetters(lettersGuessed);
for (String s : lettersLeft) {
sOut += s + " ";
}
System.out.println("Letters Left: " + sOut);
sOut = "";
for (int i = 0; i < wList.size(); i++) {
sOut += wAnswer.get(i);
}
System.out.println(sOut + " Guesses left:" + numGuesses);
System.out.print("Enter a letter(* exit): ");
String sIn = scanner.next();
numGuesses--;
if (sIn.equals("*")) {
break;
}
lettersGuessed.add(sIn);
for (int i = 0; i < wList.size(); i++) {
if (sIn.equals(wList.get(i))) {
wAnswer.set(i, sIn);
left--;
}
}
if (left == 0) {
System.out.println("Congradulations you guessed it!");
break;
}
if (numGuesses == 0) {
StringBuilder sb = new StringBuilder();
for (String string : wList) {
sb.append(string);
}
String stm = sb.toString();
System.out.println("Sorry you ran out of guesses, the word was: " + stm);
break;
}
}
}
public static void hangman(String word) {
System.out.println("Welcome to Hangman Ultimate Edition");
System.out.println("I am thinking of a word that is " + word.length() + " letters long");
System.out.println("-------------");
}
}
A sample run:
Welcome to Hangman Ultimate Edition
I am thinking of a word that is 3 letters long
-------------
Letters Left: a b c d e f g h i j k l m n o p q r s t u v w x y z
_ _ _ Guesses left:3
Enter a letter(* exit): c
Letters Left: a b d e f g h i j k l m n o p q r s t u v w x y z
_ _ _ Guesses left:2
Enter a letter(* exit): a
Letters Left: b d e f g h i j k l m n o p q r s t u v w x y z
_ _ _ Guesses left:1
Enter a letter(* exit): t
Sorry you ran out of guesses, the word was: fox

To make your existing code run, you should just clean up the main method:
remove unused code:
Main ma = new Main(); // no need to create an instance, you use only static methods
String stm= null; // not used anywhere
loadWords(); // not used, entire method may be removed:
// it reads words only in the first line
fix method function to have a String w parameter, move getting the random word out of this method.
Thus, resulting changes should be:
public static void main(String[] args) throws IOException {
String word = getRandomWord("C:\\Users\\Admin\\Documents\\NetBeansProjects\\Main\\words.txt");
hangman(word);
function(word);
}
public static void function(String w) throws IOException {
int numGuesses = 5;
String[] word = w.split("");
// ... the rest of this method remains as is
}

Multiline strings concatenation in Java

I'm looking for some help. What is the easiest way to concatenate multiline strings in Java and print it after ?
For example : I've got two strings :
String turtle1 = " _\r\n .-./*)\r\n _/___\\/\r\n U U\r";
String turtle2 = " _\r\n .-./*)\r\n _/___\\/\r\n U U\r";
And I want to get this result in the Java Eclipse console :
_ _
.-./*) .-./*)
_/___\/ _/___\/
U U U U
I've already try some algorithms to divide my strings in differents parts and after re-concatenate it. But it was without success.
I know there are StringBuffer class and StringBuilder class but after some research, I didn't found something that correspond to my need.
Thanks in advance for your help.

See my example below, should be self explaining.
public class Turtle {
private static final String returnpattern = "\r\n";
public static void main(String[] args) {
// the data to run through
String turtle1 = " _\r\n .-./*)\r\n _/___\\/\r\n U U\r\n";
String turtle2 = " _\r\n .-./*)\r\n _/___\\/\r\n U U\r\n";
// split the data into individual parts
String[] one = turtle1.split(returnpattern);
String[] two = turtle2.split(returnpattern);
// find out the longest String in data set one
int longestString = 0;
for (String s : one) {
if (longestString < s.length()) {
longestString = s.length();
}
}
// loop through parts and build new string
StringBuilder b = new StringBuilder();
for (int i = 0; i < one.length; i++) {
String stringTwo = String.format("%1$" + longestString + "s", two[i]); // left pad the dataset two to match
// length
b.append(one[i]).append(stringTwo).append(returnpattern);
}
// output
System.out.println(b);
}
}

Just for fun, here is another solution using streams, prepared for more than two turtles to be shown side-by-side:
public static void main(String[] args) {
String turtle1 = " _\r\n .-./*)\r\n _/___\\/\r\n U U\r";
String turtle2 = " _\r\n .-./*)\r\n _/___\\/\r\n U U\r";
// split lines into fragments
List<List<String>> fragments = Stream.of(turtle1, turtle2)
.map(x -> Stream.of(x.split("\\r\\n?|\\n")).collect(Collectors.toList()))
.collect(Collectors.toList());
// make all lists same length by adding empty lines as needed
int lines = fragments.stream().mapToInt(List::size).max().orElse(0);
fragments.forEach(x -> x.addAll(Collections.nCopies(lines - x.size(), "")));
// pad all fragments to maximum width (per list)
List<List<String>> padded = fragments.stream().map(x -> {
int width = x.stream().mapToInt(String::length).max().orElse(0);
return x.stream().map(y -> String.format("%-" + width + "s", y)).collect(Collectors.toList());
}).collect(Collectors.toList());
// join corresponding fragments to result lines, and join result lines
String result = IntStream.range(0, lines)
.mapToObj(i -> padded.stream().map(x -> x.get(i)).collect(Collectors.joining()))
.collect(Collectors.joining(System.lineSeparator()));
System.out.println(result);
}

Not so pretty but works:
String turtle1 = " _\r\n .-./*)\r\n _/___\\/\r\n U U\r\n";
String turtle2 = " _\r\n .-./*)\r\n _/___\\/\r\n U U\r\n";
String[] turtle1Lines = turtle1.split("\r\n");
String[] turtle2Lines = turtle2.split("\r\n");
StringBuilder sb = new StringBuilder();
int turtle1Width = 0;
for (int i = 0; i < 4; i++) {
if (turtle1Lines[i].length() > turtle1Width) {
turtle1Width = turtle1Lines[i].length();
}
}
for (int i = 0; i < 4; i++) {
sb.append(turtle1Lines[i]);
for (int j = turtle1Width - turtle1Lines[i].length(); j > 0; j--) {
sb.append(' ');
}
sb.append(turtle2Lines[i]);
sb.append("\r\n");
}
String turtles = sb.toString();

I'm here too ;)
public class Test {
static String turtle1 = " _\r\n .-./*)\r\n _/___\\/\r\n U U\r".replace("\r", "");
static String turtle2 = " _\r\n .-./*)\r\n _/___\\/\r\n U U\r".replace("\r", "");
public static int countRows(String string){
return string.length() - string.replace("\n", "").length() + 1;
}
public static int getMaxLength(String string){
int maxLength = 0;
int currentLength = 0;
char[] data = string.toCharArray();
for(Character c : data){
if(c != '\n'){
if(++currentLength > maxLength) {
maxLength = currentLength;
}
}else{
currentLength = 0;
}
}
return maxLength;
}
public static String[] toStringArray(String string){
int length = getMaxLength(string);
int rows = countRows(string);
String[] result = new String[rows];
int last = 0;
for(int i = 0; i < rows; i++){
int temp = string.indexOf("\n", last);
String str;
if(temp != -1) {
str = string.substring(last, temp);
}else{
str = string.substring(last);
}
while(str.length() < length){
str += " ";
}
result[i] = str;
last = temp + 1;
}
return result;
}
public static String concatMultilineStrings(String first, String second){
StringBuilder sb = new StringBuilder();
String[] arrayFirst = toStringArray(first);
String[] arraySecond = toStringArray(second);
if(arrayFirst.length != arraySecond.length){
System.exit(69);
}
for(int i = 0; i < arrayFirst.length; i++){
sb.append(arrayFirst[i]);
sb.append(arraySecond[i]);
sb.append("\n");
}
return sb.toString();
}
public static void main(String[] args) {
System.out.println(concatMultilineStrings(turtle1, turtle2));
}
}

Algorithm to split string with comma only in the outer braces

I want to split string only inside the first braces. How can I do it in java
Input String 1: text2(text3, text4), text5(text6, text7)
String1: text2(text3, text4)
String2: text5(text6, text7)
Input String 2: text2, text3(text4, text5(text6, text7, text8))
String1: text2
String2: text3(text4, text5(text6, text7, text8))
Input String can have arbitrary number of levels. Please assume that the input string has matching braces.
Thanks in advance

package ic.ac.uk.relationshipvisualiser.app;
import java.util.ArrayList;
import java.util.List;
public class tmpTest3 {
public static List<String> process(String p_inp) {
List<String> res = new ArrayList<String>();
p_inp = p_inp.trim();
int numberOfOpenBracketsEncountered = 0;
String t = "";
String cur = "";
for (int c=0;c<p_inp.length();c++) {
cur = p_inp.substring(c,c+1);
if (cur.equals("(")) {
numberOfOpenBracketsEncountered++;
}
if (cur.equals(")")) {
numberOfOpenBracketsEncountered--;
}
if (cur.equals(",")) {
if (numberOfOpenBracketsEncountered==0) {
if (t.length()>0) res.add(t.trim());
t = "";
} else {
cur = cur;
t = t + cur;
}
} else {
cur = cur;
t = t + cur;
}
}
if (t.length()>0) res.add(t.trim());
return res;
}
public static void main(String[] args) {
System.out.println("Start tmpTest3");
List<String> inputs = new ArrayList<String>();
inputs.add("text2(text3, text4), text5(text6, text7)");
inputs.add("text2, text3(text4, text5(text6, text7))");
for (int c=0;c<inputs.size();c++) {
System.out.println("Running test for " + inputs.get(c));
List<String> res = process(inputs.get(c));
System.out.println("Got " + res.size() + " strings as a result:");
for (int d=0;d<res.size();d++) {
System.out.println(" - :" + res.get(d) + ":");
}
System.out.println("----------------------");
}
System.out.println("End tmpTest3");
}
}

Will This works for you ..?
import java.util.Arrays;
class Program {
public static void main (String[] args) throws java.lang.Exception {
String subject1 = "text2(text3, text4), text5(text6, text7)";
String subject2 = "text2, text3(text4, text5(text6, text7))";
String p = "\\s*\\d*\\(\\)";
String[] res = subject1.split(p);
System.out.println(Arrays.toString(res));
res=subject2.split(p);
System.out.println(Arrays.toString(res));
} // end main
} // end
Out put :-
[text2(text3, text4), text5(text6, text7)]
[text2, text3(text4, text5(text6, text7))]

The program throws NullPointerException [closed]

Closed. This question needs details or clarity. It is not currently accepting answers.
Want to improve this question? Add details and clarify the problem by editing this post.
Closed 8 years ago.
Improve this question
Not sure why it gives me the NullPointerException. Please help.
I am pretty sure all the arrays are full, and i restricted all the loops not to go passed empty spaces.
import java.util.;
import java.io.;
public class TextAnalysis {
public static void main (String [] args) throws IOException {
String fileName = args[0];
File file = new File(fileName);
Scanner fileScanner = new Scanner(file);
int MAX_WORDS = 10000;
String[] words = new String[MAX_WORDS];
int unique = 0;
System.out.println("TEXT FILE STATISTICS");
System.out.println("--------------------");
System.out.println("Length of the longest word: " + longestWord(fileScanner));
read(words, fileName);
System.out.println("Number of words in file wordlist: " + wordList(words));
System.out.println("Number of words in file: " + countWords(fileName) + "\n");
System.out.println("Word-frequency statistics");
lengthFrequency(words);
System.out.println();
System.out.println("Wordlist dump:");
wordFrequency(words,fileName);
}
public static void wordFrequency(String[] words, String fileName) throws IOException{
File file = new File(fileName);
Scanner s = new Scanner(file);
int [] array = new int [words.length];
while(s.hasNext()) {
String w = s.next();
if(w!=null){
for(int i = 0; i < words.length; i++){
if(w.equals(words[i])){
array[i]++;
}
}
for(int i = 0; i < words.length; i++){
System.out.println(words[i] + ":" + array[i]);
}
}
}
}
public static void lengthFrequency (String [] words) {
int [] lengthTimes = new int[10];
for(int i = 0; i < words.length; i++) {
String w = words[i];
if(w!=null){
if(w.length() >= 10) {
lengthTimes[9]++;
} else {
lengthTimes[w.length()-1]++;
}
}
}
for(int j = 0; j < 10; j++) {
System.out.println("Word-length " + (j+1) + ": " + lengthTimes[j]);
}
}
public static String longestWord (Scanner s) {
String longest = "";
while (s.hasNext()) {
String word = s.next();
if (word.length() > longest.length()) {
longest = word;
}
}
return (longest.length() + " " + "(\"" + longest + "\")");
}
public static int countWords (String fileName) throws IOException {
File file = new File(fileName);
Scanner fileScanner = new Scanner(file);
int count = 0;
while(fileScanner.hasNext()) {
String word = fileScanner.next();
count++;
}
return count;
}
public static void read(String[] words, String fileName) throws IOException{
File file = new File(fileName);
Scanner s = new Scanner(file);
while (s.hasNext()) {
String word = s.next();
int i;
for ( i=0; i < words.length && words[i] != null; i++ ) {
words[i]=words[i].toLowerCase();
if (words[i].equals(word)) {
break;
}
}
words[i] = word;
}
}
public static int wordList(String[] words) {
int count = 0;
while (words[count] != null) {
count++;
}
return count;
}
}

There are two problems with this code
1.You didn't do null check,although the array contains null values
2.Your array index from 0-8,if you wan't to get element at 9th index it will throw ArrayIndexOutOfBound Exception.
Your code should be like that
public static void lengthFrequency (String [] words) {
int [] lengthTimes = new int [9];
for(int i = 0; i < words.length; i++) {
String w = words[i];
if(null!=w) //This one added for null check
{
/* if(w.length() >= 10) {
lengthTimes[9]++;
} else {
lengthTimes[w.length()-1]++;
}
}*/
//Don't need to check like that ...u can do like below
for(int i = 0; i < words.length; i++) {
String w = words[i];
if(null!=w)
{
lengthTimes[i] =w.length();
}
}
}
//here we should traverse upto length of the array.
for(int i = 0; i < lengthTimes.length; i++) {
System.out.println("Word-length " + (i+1) + ": " + lengthTimes[i]);
}
}

Your String Array String[] words = new String[MAX_WORDS]; is not initialized,you are just declaring it.All its content is null,calling length method in line 31 will give you null pointer exception.
`

Simple mistake. When you declare an array, it is from size 0 to n-1. This array only has indexes from 0 to 8.
int [] lengthTimes = new int [9];
//some code here
lengthTimes[9]++; // <- this is an error (this is line 29)
for(int i = 0; i < 10; i++) {
System.out.println("Word-length " + (i+1) + ": " + lengthTimes[i]); // <- same error when i is 9. This is line 37

When you declare:
String[] words = new String[MAX_WORDS];
You're creating an array with MAX_WORDS of nulls, if your input file don't fill them all, you'll get a NullPointerException at what I think is line 37 in your original file:
if(w.length() >= 10) { // if w is null this would throw Npe
To fix it you may use a List instead:
List<String> words = new ArrayList<String>();
...
words.add( aWord );
Or perhaps you can use a Set if you don't want to have repeated words.