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Textfield JavaFX with dynamic mask for monetary values (Using TextFormatter)

i'm using TextFomater to make my TextField as a dynamic monetary textfield, using the following code:
public class MoneyTextFieldOperator implements UnaryOperator<TextFormatter.Change>
{
final char seperatorChar = '.';
final Pattern p;
int length;
public MoneyTextFieldOperator(int length) {
this.length=length;
this.p = Pattern.compile("[0-9. ]*");
}
#Override
public TextFormatter.Change apply(final TextFormatter.Change c) {
if (c.isContentChange() && c.getControlNewText().length() > length) {
return null;
}
else {
if (!c.isContentChange()) {
return c;
}
final String newText = c.getControlNewText();
if (newText.isEmpty()) {
return c;
}
if (!this.p.matcher(newText).matches()) {
return null;
}
final int suffixCount = c.getControlText().length() - c.getRangeEnd();
int digits = suffixCount - suffixCount / 4;
final StringBuilder sb = new StringBuilder();
if (digits % 3 == 0 && digits > 0 && suffixCount % 4 != 0) {
sb.append('.');
}
for (int i = c.getRangeStart() + c.getText().length() - 1; i >= 0; --i) {
final char letter = newText.charAt(i);
if (Character.isDigit(letter)) {
sb.append(letter);
if (++digits % 3 == 0) {
System.out.println("digits : "+digits);
sb.append('.');
}
}
}
if (digits % 3 == 0) {
sb.deleteCharAt(sb.length() - 1);
}
sb.reverse();
final int length = sb.length();
c.setRange(0, c.getRangeEnd());
c.setText(sb.toString());
c.setCaretPosition(length);
c.setAnchor(length);
return c;
}}
And calling it as follow :
montantTextField.setTextFormatter(new TextFormatter(new MoneyTextFieldOperator(10)));
the issue is that it's valable just for integer numbers, and i want make it now valable for decimal numbers, so when the user type 254648,32
it converts it to 254.648,32

here is a proposed solution using numberformat :
public class MoneyTextFieldOperator implements UnaryOperator<TextFormatter.Change> {
Pattern p;
int length;
public MoneyTextFieldOperator(int length) {
this.length = length;
this.p = Pattern.compile("[0-9. ,]*");
}
#Override
public TextFormatter.Change apply(TextFormatter.Change c) {
Pattern acceptedKeywords = Pattern.compile("[0-9 . ,]*");
int wholeNumberLength = 9;
int decimalPartLength = 2;
String newText = c.getControlNewText();
String wholeNumber;
String decimalPart;
if (newText.contains(",")) {
wholeNumber = newText.substring(0, newText.indexOf(","));
decimalPart = newText.substring(newText.indexOf(",") + 1, newText.length());
} else {
wholeNumber = newText;
decimalPart = "";
}
Matcher matcher = acceptedKeywords.matcher(newText);
boolean isMatchingWithAcceptedKeywords = matcher.matches();
String letter = c.getText();
if (newText.isEmpty()) {
return c;
} else if (!c.isContentChange()) {
return c;
} else if (countChar(c.getControlNewText(), ',') > 1) {
return null;
} else if (!isMatchingWithAcceptedKeywords) {
return null;
} else if (wholeNumber.replace(".", "").length() > wholeNumberLength || decimalPart.length() > decimalPartLength) {
return null;
} else if (c.getControlNewText().charAt(0)==',') {
return null;
}
else {
c.setRange(0, c.getControlText().length());
if (newText.contains(",")) {
c.setText(NumbersTools.getMonetaryFormat(Integer.parseInt(wholeNumber.replace(".", ""))) + "," + decimalPart);
} else {
c.setText(NumbersTools.getMonetaryFormat(Integer.parseInt(wholeNumber.replace(".", ""))));
}
c.setCaretPosition(c.getText().length());
c.setAnchor(c.getText().length());
return c;
}
}
public int countChar(String string, char charactere) {
int x = 0;
for (int i = 0; i <= string.length() - 1; ++i) {
if (string.charAt(i) == charactere) {
++x;
}
}
return x;
}
and you use it as follow :
textField.setTextFormatter(new TextFormatter<Object>(new MoneyTextFieldOperator(10)));

Writing simple String hashMap using parallel arrays. Getting null value for some keys after rehashing

The first time I get the collision in put method ie when hasKey returns -1 the rehashing method starts and value that triggered collision goes to doubled array to likely empty slot. But System.out.println(m.get("1000")); gives me null for some keys which means they were lost. I don't understand how they could be lost because there is nothing to override them in keyArray.
import java.util.*;
public class StringMapParallel implements Iterable<String>{
private int nButckets = 2000;
private String[] keyArray = new String[nButckets];
private String[] valueArray = new String[nButckets];
private int numberOfEntries = 0;
public static void main(String[] args) {
StringMapParallel m = new StringMapParallel();
;
for (int i = 0; i < 8000; i++) {
m.put(String.valueOf(i), String.valueOf(i));
}
System.out.println(m.get("1000"));
}
private void rehashing() {
if (numberOfEntries > (int) (0.3 * nButckets)) {
int newBucketsNumber = nButckets * 2;
String[] newKeyArray = new String[newBucketsNumber];
String[] newValueArray = new String[newBucketsNumber];
for (int i = 0; i < keyArray.length; i++) {
if (keyArray[i] != null) {
int index = keyArray[i].hashCode() % newBucketsNumber;
newKeyArray[index] = keyArray[i];
newValueArray[index] = valueArray[keyArray[i].hashCode() % nButckets];
}
}
/*
for (String key: this) {
int index = key.hashCode() % newBucketsNumber;
newKeyArray[index] = key;
if (key == null) System.out.println(key);
newValueArray[index] = valueArray[key.hashCode() % nButckets];
}
*/
keyArray = newKeyArray;
valueArray = newValueArray;
nButckets = newBucketsNumber;
}
}
public void put(String key, String value) {
int index = key.hashCode() % nButckets;
int hasKey = hasKey(index, key);
if (hasKey == 1) {
valueArray[index] = value;
} else if (hasKey == 0){
keyArray[index] = key;
valueArray[index] = value;
numberOfEntries++;
} else {
rehashing();
index = key.hashCode() % nButckets;
keyArray[index] = key;
valueArray[index] = value;
numberOfEntries++;
}
}
public String get(String key) {
int index = key.hashCode() % nButckets;
if (hasKey(index, key) == 1) return valueArray[index];
return null;
}
private int hasKey(int index, String key) {
if (keyArray[index] == null) {
return 0;
} else if (keyArray[index].equals(key)) {
return 1;
} else {
return -1;
}
}
public Iterator<String> iterator(){
Iterator<String> iter = new Iterator<String>() {
private int currentIndex = 0;
private int nEntries = 0;
#Override
public boolean hasNext() {
return nEntries < numberOfEntries && numberOfEntries != 0;
}
#Override
public String next() {
for (int i = currentIndex; i < keyArray.length; i++) {
if (keyArray[i] != null) {
currentIndex = i + 1;
nEntries++;
return keyArray[i];
}
}
return null;
}
};
return iter;
}
}

The value of int index = key.hashCode() % nButckets; in your algorithm for key 1000 and 6357 is same, which is 1423. Hence, the your algorithm overwrites keyArray[1423]=1000 with keyArray[1423]=6357
When you are printing m.get(String.valueOf(1000)), following get() method checks for index as well as key, hence it would return null. Read comment in the code for further explanation.
public String get(String key) {
//System.out.println(key+" "+ key.hashCode());
int index = key.hashCode() % nButckets;
System.out.println(index+"bfb"+hasKey(index, key));
//hasKey(index, key) would return -1, because key[1423] is 6357, and not 1000 as you expected.
if (hasKey(index, key) == 1) return valueArray[index];
return null;
}
private int hasKey(int index, String key) {
//System.out.println(keyArray[index]);
if (keyArray[index] == null) {
return 0;
} else if (keyArray[index].equals(key)) {
return 1;
} else {
return -1;
}
}

How to calculate the median for every insertion in a priority queue in java?

I read objects(Movies) from a file and i compare based on their likes. I want to get the median after every Movie insertion in the queue. In the code below there are :
Movie method compareTo
PQ insert and getMax methods with swim and sink
Main class
I'm creating both priority queues for higher and less objects than median, but i don't know how to dynamically calculate it. Every movie element is created with id, title, likes in this order.
public int compareTo(Movie m) {
if (this.likes == m.likes) {
return -this.title.compareTo(m.title);
} else if (this.likes > m.likes) {
return 1;
} else {
return -1;
}
}
public class PQ {
private Movie[] pq;
private int size;
public PQ(int capacity) {
if (capacity < 1) {
throw new IllegalArgumentException();
}
this.pq = new Movie[capacity + 1];
this.size = 0;
}
public void insert(Movie movie) {
if (this.size == this.pq.length - 1) {
throw new IllegalArgumentException();
}
if (movie == null) {
throw new IllegalArgumentException();
}
this.size++;
this.pq[this.size] = movie;
swim(this.size);
}
public void swim(int i) {
while (i > 1) {
int p = i / 2;
int result = this.pq[p].compareTo(this.pq[i]);
if (result <= 0)
return;
swap(i, p);
i = p;
}
}
public Movie Max() {
if (this.size == 0)
throw new IllegalArgumentException();
return this.pq[1];
}
public Movie getMax() {
if (this.size == 0)
throw new IllegalArgumentException();
Movie m = this.pq[1];
if (this.size > 1)
this.pq[1] = this.pq[this.size];
this.pq[this.size--] = null;
sink(1);
return m;
}
private void sink(int i) {
int left = 2 * i;
int right = left + 1;
int max = left;
while (left <= this.size) {
if (right <= this.size) {
max = this.pq[right].compareTo(this.pq[left]) < 0 ? right
: left;
}
if (this.pq[max].compareTo(this.pq[i]) >= 0)
return;
swap(i, max);
i = max;
left = 2 * i;
right = left + 1;
max = left;
}
}
private void swap(int i, int j) {
Movie tmp = pq[i];
pq[i] = pq[j];
pq[j] = tmp;
}
}
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
public class Dynamic_Median {
public static void main(String[] args) {
BufferedReader br = null;
PQ higher_median = new PQ(4);
PQ less_median = new PQ(4);
Movie median = null;
try { // try to read the file
br = new BufferedReader(new FileReader("movies.txt"));
String line;
String title = "";
int id = 0;
int likes = 0;
while ((line = br.readLine()) != null) {
line = line.trim();
line = line.replaceAll("/t", "");
String[] tokens = line.split(" "); // store every token in an
// String array
id = Integer.parseInt(tokens[0]);
likes = Integer.parseInt(tokens[tokens.length - 1]);
for (int i = 1; i < tokens.length - 1; i++) {
title = title + " " + tokens[i];
}
title = "";
}
} catch (IOException e) {
e.printStackTrace();
}
}
}

ki esy re kopela mou teleftaia mera ths prothesmias thymithikes na rwthseis? :P

Displaying search results from a hash table

I can't figure out how to display the results from my search method. I put strings in where it needs to display the results.
Here is the client class
public class Client
{
private String name;
private String city;
public Client(String name, String city)
{
this.name = name;
this.city = city;
}
public String toString()
{
return name + " " + city;
}
public String getName()
{
return name;
}
public String getCity()
{
return city;
}
}
Here is my Hashtable class
public class Hashtable {
private int n;
private Client[] table;
public Hashtable(int n) {
this.n = n;
table = new Client[n];
}
public int hashFunction(String key) {
int sum = 0;
for (int i = 0; i < key.length(); i++) {
sum += (int) key.charAt(i);
}
sum = sum%n;
return sum;
}
public String search(String key) {
int sum = 0;
for (int i = 0; i < key.length(); i++) {
sum += (int) key.charAt(i);
}
sum = sum%n;
if (key.equals(table[sum])) {
return ("Returns the toString from the client class here");
} else if (table[sum] == null) {
return null;
} else {
while (table[sum] != null) {
sum++;
}
return ("Returns the toString from the client class here");
}
}
public boolean insert(Client myClient) {
int counter = 0;
String temp = myClient.getName();
boolean ret = false;
int tempSum = 0;
for (int i = 0; i < temp.length(); i++) {
tempSum += (int) temp.charAt(i);
}
tempSum = tempSum%n;
if (table[tempSum] == null) {
table[tempSum] = myClient;
ret = true;
} else {
while (table[tempSum] != null) {
if(tempSum == table.length){
tempSum = -1;
}
tempSum++;
counter++;
}
if(counter != n){
ret = true;
table[tempSum] = myClient;
}
}
return ret;
}
}

When you are comparing the key in search method, Make sure you compare against name.
Change table[sum] to table[sum].getName() ???? I modified the code and added comments for the change.
public class Hashtable {
private int n;
private Client[] table;
public Hashtable(int n) {
this.n = n;
table = new Client[n];
}
public int hashFunction(String key) {
int sum = 0;
for (int i = 0; i < key.length(); i++) {
sum += (int) key.charAt(i);
}
sum = sum%n;
return sum;
}
public String search(String key) {
int sum = 0;
for (int i = 0; i < key.length(); i++) {
sum += (int) key.charAt(i);
}
sum = sum%n;
if (key.equals(table[sum].getName())) { //This Should be table[sum].getName()
return ("Returns the toString from the client class here");
} else if (table[sum] == null) {
return null;
} else {
while (table[sum] != null) {
sum++;
}
return ("Returns the toString from the client class here");
}
}
public boolean insert(Client myClient) {
int counter = 0;
String temp = myClient.getName();
boolean ret = false;
int tempSum = 0;
for (int i = 0; i < temp.length(); i++) {
tempSum += (int) temp.charAt(i);
}
tempSum = tempSum%n;
if (table[tempSum] == null) {
table[tempSum] = myClient;
ret = true;
} else {
while (table[tempSum] != null) {
if(tempSum == table.length){
tempSum = -1;
}
tempSum++;
counter++;
}
if(counter != n){
ret = true;
table[tempSum] = myClient;
}
}
return ret;
}
}
Let me know if that helped

Odd return on PEMDAS calculator

It seems that this calculator works for all other cases, except cases like this:
(2*3^4)
It does not return 162, instead, it returns 0.0.
I identified that the error must be from the method public static double operation, since the default return statement is 0.0
Here is the code:
import java.util.Iterator;
import java.util.NoSuchElementException;
public class StackC<Item> implements Stack<Item> {
private Item[] a; // array of items
private int N; // number of elements on stack
public StackC() {
a = (Item[]) new Object[2];
}
public boolean isEmpty() {
return N == 0;
}
public int size() {
return N;
}
private void resize(int capacity) {
assert capacity >= N;
Item[] temp = (Item[]) new Object[capacity];
for (int i = 0; i < N; i++) {
temp[i] = a[i];
}
a = temp;
}
public void push(Item item) {
if (N == a.length) resize(2*a.length); // double size of array if necessary
a[N++] = item; // add item
}
public Item pop() {
if (isEmpty())
throw new NoSuchElementException("Stack underflow");
Item item = a[N-1];
a[N-1] = null; // to avoid loitering
N--;
// shrink size of array if necessary
if (N > 0 && N == a.length/4)
resize(a.length/2);
return item;
}
public Item peek() {
if (isEmpty())
throw new NoSuchElementException("Stack underflow");
return a[N-1];
}
public Iterator<Item> iterator() {
return new ReverseArrayIterator();
}
private class ReverseArrayIterator implements Iterator<Item> {
private int i;
public ReverseArrayIterator() {
i = N;
}
public boolean hasNext() {
return i > 0;
}
public void remove() {
throw new UnsupportedOperationException();
}
public Item next() {
if (!hasNext()) throw new NoSuchElementException();
return a[--i];
}
}
//---------------------------------------------------------------------
public static void main(String[] args) {
StackC<String> Operator = new StackC<String>();
StackC<Double> Values = new StackC<Double>();
while (!StdIn.isEmpty()) {
String token = StdIn.readString();
try {
Double x = Double.parseDouble(token);
Values.push(x);
}
catch(NumberFormatException nFE) {
}
if (token.equals("("))
Operator.push(token);
if (token.equals(")"))
{
if (Operator.peek() != "(")
{
String type = Operator.pop();
double b = Values.pop();
double a = Values.pop();
Values.push(operation(type,a,b));
}
Operator.pop();
}
if(token.equals("*") || token.equals("+") || token.equals("/") || token.equals("-") || token.equals("^") )
{
if(!Operator.isEmpty())
{
String prev = Operator.peek();
int x = comparePrecedence(token, Operator.peek()); // You need to compare precedence first
if(x == -1 || x == 0)
{
String type = Operator.pop();
double b = Values.pop();
double a = Values.pop();
Values.push(operation(type,a,b));
}
}
Operator.push(token);
}
}
while(!Operator.isEmpty())
{
String prev = Operator.peek();
String type = Operator.pop();
double b = Values.pop();
double a = Values.pop();
Values.push(operation(type,a,b));
}
System.out.println(Values.pop());
}
public static double operation(String operator, double a, double b) {
if (operator.equals("+"))
return a + b;
else if (operator.equals("-"))
return a - b;
else if (operator.equals("*"))
return a * b;
else if (operator.equals("/"))
return a / b;
else if (operator.equals("^"))
return Math.pow(a,b);
return 0.0;
}
public static int comparePrecedence(String x, String y)
{
int val1 = 0;
int val2 = 0;
if(x.equals("-"))
val1 = 0;
if(y.equals("-"))
val2 = 0;
if(x.equals("+"))
val1 = 1;
if(y.equals("+"))
val2 = 1;
if(x.equals("/"))
val1 = 2;
if(y.equals("/"))
val2 = 2;
if(x.equals("*"))
val1 = 3;
if(y.equals("*"))
val2 = 3;
if(x.equals("^"))
val1 = 4;
if(y.equals("^"))
val2 = 4;
if(val1 > val2)
return 1;
else if(val2 > val1)
return -1;
else
return 0;
}
}
Everything above the dotted line was given via the professor, and is not the problem for the code.
StdIn is simply a method that reads inputs.