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Java- function seems to mess up the console, nothing will be printed out after calling the function

I was asked to program a method that receives a scanner, and returns a sorted array of words which contain only letters, with no repetitions (and no bigger in length than 3000). Then, I was asked to program a method that checks whether a certain given string is contained in a given vocabulary. I used a simple binary search method.
This is what I've done:
public static String[] scanVocabulary(Scanner scanner){
String[] array= new String[3000];
int i=0;
String word;
while (scanner.hasNext() && i<3000) {
word=scanner.next();
if (word.matches("[a-zA-Z]+")){
array[i]=word.toLowerCase();
i++;
}
}int size=0;
while (size<3000 && array[size]!=null ) {
size++;
}
String[] words=Arrays.copyOf(array, size);
if (words.length==0 || words.length==1) {
return words;
}
else {
Arrays.sort(words);
int end= removeDuplicatesSortedArr(words);
return Arrays.copyOf(words, end);
}
}
private static int removeDuplicatesSortedArr(String[] array) { //must be a sorted array. returns size of the new array
int n= array.length;
int j=0;
for (int i=0; i<n-1; i++) {
if (!array[i].equals(array[i+1])) {
array[j++]=array[i];
}
}
array[j++]=array[n-1];
return j;
}
public static boolean isInVocabulary(String[] vocabulary, String word){
//binary search
int n=vocabulary.length;
int left= 0;
int right=n-1;
while (left<=right) {
int mid=(left+right)/2;
if (vocabulary[mid].equals(word)){
return true;
}
else if (vocabulary[mid].compareTo(word)>0) {
right=mid-1;
}else {
right=mid+1;
}
}
return false;
}
while trying the following code:
public static void main(String[] args) {
String vocabularyText = "I look at the floor and I see it needs sweeping while my guitar gently weeps";
Scanner vocabularyScanner = new Scanner(vocabularyText);
String[] vocabulary = scanVocabulary(vocabularyScanner);
System.out.println(Arrays.toString(vocabulary));
boolean t=isInVocabulary(vocabulary, "while");
System.out.println(t);
System.out.println("123");
}
I get nothing but-
[and, at, floor, gently, guitar, i, it, look, my, needs, see, sweeping, the, weeps, while]
nothing else is printed out nor returned. Both functions seem to be working fine separately, so I don't get what I'm doing wrong.
I would be very happy to hear your thoughts, thanks in advance :)

This has nothing to do with the console. Your isInVocabulary method is entering an infinite loop in this block:
if (!isInVocabulary(vocabulary, "while")) {
System.out.println("Error");
}
If you were to debug through isInVocabulary, you would see that after a few iterations of the while loop,
left = 0;
right = 2;
mid = 1;
if (vocabulary[mid].equals(word)){
// it doesn't
} else if (vocabulary[mid].compareTo("while") > 0) {
// it doesn't
} else {
right = mid + 1;
// this is the same as saying right = 1 + 1, i.e. 2
}
So you'll loop forever.

JAVA error cannot find a symbol

I need to create a JAVA method: public static int[] Numb() that reads and returns a series of positive integer values. If the user enters -1 we should stop accepting values, and then I want to call it in the main method. And we should return to the user integers that he entered them, with the total number.
So if he entered the following:
5 6 1 2 3 -1
So the total number is : 6
The numbers entered are: 5 6 1 2 3 -1
I tried the following:
class Ideone
{
public static void main (String[] args) throws java.lang.Exception
{
// your code goes here
}
public static int[] readNumbers(int[] n)
{
int[] a = new int[n.length];
Scanner scan = new Scanner(System.in);
for(int i = 0;i<n.length;i++) {
String token = scan.next();
a[i] = Integer.nextString();
}
}
}
And here is a fiddle of them. I have an error that said:
Main.java:21: error: cannot find symbol
a[i] = Integer.nextString();
I am solving this exercise step by step, and I am creating the method that reads integers. Any help is appreciated.

Integer.nextString() doesn't exist, to get the next entered integer value, you may change your loop to either :
for(int i = 0;i<n.length;i++) {
a[i] = scan.nextInt();
}
or as #vikingsteve suggested :
for(int i = 0;i<n.length;i++) {
String token = scan.next();
a[i] = Integer.parseInt(token);
}

public static void main(String[] args) {
List<Integer> numList = new ArrayList<>();
initializeList(numList);
System.out.println("Num of integer in list: "+numList.size());
}
public static void initializeList(List<Integer> numList) {
Scanner sc = new Scanner(System.in);
boolean flag = true;
while(flag) {
int num = sc.nextInt();
if(num==-1) {
flag = false;
}else {
numList.add(num);
}
}
sc.close();
}
Since the number of integers is unknown, use ArrayList. It's size can be altered unlike arrays.
You can create something like arraylist on your own..it can be done like this:
public class Test {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
CustomArray c = new CustomArray(3);
boolean flag = true;
while (flag) {
int num = sc.nextInt();
if (num == -1) {
flag = false;
} else {
c.insert(num);
}
System.out.println(Arrays.toString(c.numList));
}
sc.close();
}
}
class CustomArray {
int[] numList;
int size; // size of numList[]
int numOfElements; // integers present in numList[]
public CustomArray(int size) {
// TODO Auto-generated constructor stub
numList = new int[size];
this.size = size;
numOfElements = 0;
}
void insert(int num) {
if (numOfElements < size) {
numList[numOfElements++] = num;
} else {
// list is full
size = size * 2; //double the size, you can use some other factor as well
//create a new list with new size
int[] newList = new int[size];
for (int i = 0; i < numOfElements; i++) {
//copy all the elements in new list
newList[i] = numList[i];
}
numList = newList;//make numList equal to new list
numList[numOfElements++] = num;
}
}
}

Using standard input in java, how to input an entire array of integers? [duplicate]

This question already has answers here:
How to read array of integers from the standard input in Java?
(2 answers)
Closed 8 years ago.
So my code looks like this so far:
public class PancakeSort {
public static int flip(int n) {
int temp = 0;
for (int i = 0; i < (n+1) / 2; ++i) {
int[] pancakes = new int[n];
temp = pancakes[i];
pancakes[i] = pancakes[n-i];
pancakes[n-i] = temp;
}
return temp;
}
public static void sort (int[] pancakes) {
for (int i=0; i<pancakes.length; i++){
if (pancakes[i] > pancakes[i+1]){
flip(i+1);
}
}
System.out.println(pancakes);
}
public static void main(String[] args) {
}
}
But how I input a whole array of integers using standard input (StdIn.readLine())? I understand that the code might not be correct and I'm working on figuring that out,and I'm also aware that this question has been asked before in this site, but not specifically using the standard library and that is where I'm stuck.

You can send integer array as input
PancakeSort pancakeSort = new PancakeSort();
pancakeSort.sort(new int[] { 100, 50, 89, 2, 5, 150 });
or Use scanner class as
int arr[] = new int[10];
Scanner sc = new Scanner(System.in);
int i = 0;
while (sc.hasNextInt()) {
arr[i] = sc.nextInt();
i = i + 1;
}
PancakeSort pancakeSort = new PancakeSort();
pancakeSort.sort(arr);
But in last case you must not increased the size of array.Otherwise it will give arrayIndexOutOfBoundException

I believe you may be referencing StdIn such as a class like this one?
http://introcs.cs.princeton.edu/java/stdlib/StdIn.java.html
If so, then to get an int from the console you just call StdIn.readInt. An example of how you could approach this is:
public static void main(String[] args)
{
System.out.println("Enter number of pancakes, or enter 0 to quit");
int[] pancakeArray = new int[0];
while (true)
{
try
{
int entry = StdIn.readInt();
if (entry == 0)
{
break;
}
int[] expandedArray = new int[pancakeArray.length + 1];
System.arraycopy(pancakeArray, 0, expandedArray, 0, pancakeArray.length);
expandedArray[pancakeArray.length] = entry;
pancakeArray = expandedArray;
}
catch (Exception e)
{
System.out.println("Invalid entry detected, closing input");
break;
}
}
System.out.println("Pancake array length: " + pancakeArray.length);
sort(pancakeArray);
System.out.println("Final pancake array in order:");
for (int entry : pancakeArray)
{
System.out.println("Pancake value: " + entry);
}
}
This would read int after int until they entered 0 or an invalid value, then it would call your sort routine from there. There are issues in your sort routine but you said you wanted to look at that, so I will let you figure that part out.

IndexOutOfBoundsException while accessing List

I'm working on a project for a class, and I think I've got it mostly figured out, but it keeps giving me different Exception errors and now I'm stumped.
The instructions can be found here: http://www.cse.ohio-state.edu/cse1223/currentsem/projects/CSE1223Project11.html
Here is the code I have thus far, currently giving me and IndexOutOfBounds exception in the getMaximum method.
Any help would be much appreciated.
import java.io.*;
import java.util.*;
public class Project11a {
public static void main(String[] args) throws FileNotFoundException {
Scanner keyboard = new Scanner(System.in);
System.out.print("Enter an input file name: ");
String fileName = keyboard.nextLine();
Scanner in = new Scanner(new File(fileName));
System.out.print("Enter an output file name: ");
String outFile = keyboard.nextLine();
PrintWriter outputFile = new PrintWriter(outFile);
while (in.hasNextLine()) {
String name = in.nextLine();
List<Integer> series = readNextSeries(in);
int mean = getAverage(series);
int median = getMedian(series);
int max = getMaximum(series);
int min = getMinimum(series);
outputFile.printf("%-22s%6d%n", name, mean, median, max, min);
}
in.close();
outputFile.close();
}
// Given a Scanner as input read in a list of integers one at a time until a
// negative
// value is read from the Scanner. Store these integers in an
// ArrayList<Integer> and
// return the ArrayList<Integer> to the calling program.
private static List<Integer> readNextSeries(Scanner inScanner) {
List<Integer> nextSeries = new ArrayList<Integer>();
while (inScanner.hasNextInt()) {
int currentLine = inScanner.nextInt();
if (currentLine != -1) {
nextSeries.add(currentLine);
} else {
break;
}
}
return nextSeries;
}
// Given a List<Integer> of integers, compute the median of the list and
// return it to
// the calling program.
private static int getMedian(List<Integer> inList) {
Collections.sort(inList);
int middle = inList.size() / 2;
int median = -1;
if (inList.size() % 2 == 1) {
median = inList.get(middle);
} else {
try {
median = (inList.get(middle - 1) + inList.get(middle)) / 2;
} catch (Exception e) {
}
}
return median;
}
// Given a List<Integer> of integers, compute the average of the list and
// return it to
// the calling program.
private static int getAverage(List<Integer> inList) {
int average = 0;
if (inList.size() == 0) {
return 0;
}
for (int i = 0; i < inList.size(); i++) {
average += inList.get(i);
}
return (average / inList.size());
}
// Given a List<Integer> of integers, compute the maximum of the list and
// return it to
// the calling program.
private static int getMaximum(List<Integer> inList) {
int max = inList.get(0);
for (int i = 1; i < inList.size(); i++) {
if (inList.get(i) > max) {
max = inList.get(i);
}
}
return max;
}
// Given a List<Integer> of integers, compute the maximum of the list and
// return it to
// the calling program.
private static int getMinimum(List<Integer> inList) {
int min = inList.get(0);
for (int i = 1; i < inList.size(); i++) {
if (inList.get(i) < min) {
min = inList.get(i);
}
}
return min;
}
}

Seemed like that your list is empty.
What can triggered the exception is the statement:
int max = inList.get(0);
So your inList do not have the value in the first index,which means the inList is empty.

Using imported data Java

I'm just learning to use File I/O and struggling to figure out how to use the data. For example, I have a .txt file that is setup with a name and list of scores that apply to that name, each list ending with a -1. I have successfully imported the file and was able to print it on the console but I need to add this information to an ArrayList so I can sort it, find the high and low, and the average and median. When I attempt to enter the data into an ArrayList I get a Exception I don't know how to handle. Here is the code I have so far, any help would be appreciated.
public static void main(String[] args) throws IOException {
File file = new File("Project11input.txt");
Scanner inFile = new Scanner(file);
ArrayList<Integer> TerryCrews = readNextSeries(inFile);
int median = getMedian(TerryCrews);
System.out.println("The median is " + median);
int average = getAverage(TerryCrews);
System.out.println("The average is " + average);
}
private static ArrayList<Integer> readNextSeries(Scanner inScanner) {
ArrayList<Integer> Input = new ArrayList<Integer>();
int thesex = 0;
while(thesex >= 0){
thesex = inScanner.nextInt();
Input.add(thesex);
}
System.out.println("End of input");
return Input;}
private static int getMedian(ArrayList<Integer> inList) {
int last = 0;
int power = (inList.size()/2) - 1;
int pow=0;
int ful = power+1;
int wap =0;
int onetwo = inList.size()%2;
if(onetwo == 1){
last = inList.get(ful);}
else{
pow = inList.get(power);
wap = inList.get(ful);
last = (pow + wap);
last=last/2;
}
return last; }
to clarify, I basically need the numbers in the File "file" to be in an ArrayList so they can be used.