FileWriter not writing to .txt file - java

I'm trying to get the "test" or whatever to be printed out inside a file called doctor.txt.
Whenever I run the program, it just comes out to be blank on the file. Also, do you have to make the .txt in the folder beforehand, or does it automatically make the file for you?
Here's my code:
import java.util.Scanner;
import java.io.File;
import java.io.IOException;
import java.io.FileWriter;
public class Vowels {
public static void main(String [] args) {
try {
int countA = 0;
int countE = 0;
int countI = 0;
int countO = 0;
int countU = 0;
Scanner in = new Scanner(new File("poetry.txt"));
String poetry = "";
while(in.hasNext()){
poetry = in.nextLine();
poetry = poetry.replaceAll(" ", "~");
System.out.println(poetry);
for(int v = 0; v < poetry.length(); v++) {
if(poetry.charAt(v) == 'a') {
countA++;
}
if(poetry.charAt(v) == 'e') {
countE++;
}
if(poetry.charAt(v) == 'i') {
countI++;
}
if(poetry.charAt(v) == 'o') {
countO++;
}
if(poetry.charAt(v) == 'u') {
countU++;
}
}
}
System.out.println();
System.out.println("The number of 'A's is: " + countA);
System.out.println("The number of 'E's is: " + countE);
System.out.println("The number of 'I's is: " + countI);
System.out.println("The number of 'O's is: " + countO);
System.out.println("The number of 'U's is: " + countU);
FileWriter doctor = new FileWriter("doctor.txt");
doctor.write("test");
}
catch(IOException i) {
System.out.println("Error: " + i.getMessage());
}
}

Put doctor.close(); after doctor.write("test");.

Related

Guessing letter without having to capitalize input

I am new to this and I am having hard time with this code. I made a hangman game but I am having issues with the words that have a capital letter. If I don't input a capital letter the letter will not appear.
Here is my code:
import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class Hangman {
static ArrayList<String> words = new ArrayList<>();
static boolean isCorrect;
private static Scanner input;
private static Scanner input2;
public static void main(String[] args) {
File filename = new File("hangman.txt");
if (!filename.exists()) {
System.out.println(filename.getAbsolutePath());
System.out.println(filename + " does not exist.");
System.exit(1);
}
try {
input2 = new Scanner(filename);
while (input2.hasNext()) {
words.add(input2.next());
}
} catch (FileNotFoundException ex) {
ex.printStackTrace();
}
input2.close();
input = new Scanner(System.in);
String playStarts = "y";
int wins = 0;
int loses = 0;
final int MAX_GUESSES = 11;
List<String> usedWords = new ArrayList<>();
while (playStarts.equals("y")) {
String word = getWord();
usedWords.add(word);
String secretWord = getSecretWord(word);
int missCount = 0;
while (!word.equals(secretWord)) {
System.out.print("(Guess) Enter a letter in word " + secretWord + " > ");
char ch = input.next().charAt(0);
if (!isAlreadyInWord(secretWord, ch)) {
secretWord = getGuess(word, secretWord, ch);
if (!isCorrect) {
System.out.print(ch + " is not in the word.");
missCount++;
System.out.println(" You missed "+ missCount + " times");
}
} else {
System.out.println(ch + " is already in word.");
}
if (missCount == MAX_GUESSES) {
System.out.println("You reached max number of guesses.");break;
}
}
if (missCount == MAX_GUESSES) {
loses++;
} else {
wins++;
}
System.out.println("The word is " + word + ". You missed " + missCount + " times");
System.out.println("Do you want to guess another word? Enter y or n >");
playStarts = input.next();
}
System.out.println("Number of wins is " + wins + ".");
System.out.println("Number of loses is " + loses + ".");
System.out.println("Used words:");
for (String word : usedWords) {
System.out.println(word);
}
input.close();
}
public static String getWord() {
return words.get((int) (Math.random() * words.size()));
}
public static String getSecretWord(String word) {
String hidden = "";
for (int i = 0; i < word.length(); i++) {
hidden += "*";
}
return hidden;
}
static public String getGuess(String word, String secretWord, char ch) {
isCorrect = false;
StringBuilder s = new StringBuilder(secretWord);
for (int i = 0; i < word.length(); i++) {
//I think the issue is in this section of the code:
if (ch == word.charAt(i) && s.charAt(i) == '*') {
isCorrect = true;
s = s.deleteCharAt(i);
s = s.insert(i, ch);
}
}
return s.toString();
}
public static boolean isAlreadyInWord(String secretWord, char ch) {
for (int i = 0; i < secretWord.length(); i++) {
if (ch == secretWord.charAt(i)) {
return true;
}
}
return false;
}
}
The code works fine but I just have an issue with the capitalization.
If your speculation be correct, the comparing the lowercase of both sides of the equation should fix the problem:
if (Character.toLowerCase(ch) == Character.toLowerCase(secretWord.charAt(i)) {
return true;
}
Better yet, you can lowercase the user character input when it actually happens:
System.out.print("(Guess) Enter a letter in word " + secretWord + " > ");
char ch = input.next().toLowerCase().charAt(0);
There are some handy functions in the Character class that you can use (Character.toUpperCase() and toLowerCase()) that can help you compare whether the characters match.
if (Character.toLowerCase(ch) == Character.toLowerCase(word.charAt(i)) && s.charAt(i) == '*') will always be checking two lowercase letters, so the case of neither ch or word.charAt(i) will matter.

How to return a string?

import java.util.*;
public class HangManP5
{
public static void main(String[] args)
{
int attempts = 10;
int wordLength;
boolean solved;
Scanner k = new Scanner(System.in);
System.out.println("Hey, what's your name?");
String name = k.nextLine();
System.out.println(name+ ", hey! This is a hangman game!\n");
RandomWord(word);
int len = word.length();
char[] temp = new char[len];
for(int i = 0; i < temp.length; i++)
{
temp[i] = '*';
}
System.out.print("\n");
System.out.print("Word to date: ");
while (attempts <= 10 && attempts > 0)
{
System.out.println("\nAttempts left: " + attempts);
System.out.print("Enter letter: ");
String test = k.next();
if(test.length() != 1)
{
System.out.println("Please enter 1 character");
continue;
}
char testChar = test.charAt(0);
int foundPos = -2;
int foundCount = 0;
while((foundPos = word.indexOf(testChar, foundPos + 1)) != -1)
{
temp[foundPos] = testChar;
foundCount++;
len--;
}
if(foundCount == 0)
{
System.out.println("Sorry, didn't find any matches for " + test);
}
else
{
System.out.println("Found " + foundCount + " matches for " + test);
}
for(int i = 0; i < temp.length; i++)
{
System.out.print(temp[i]);
}
System.out.println();
if(len == 0)
{
break; //Solved!
}
attempts--;
}
if(len == 0)
{
System.out.println("\n---------------------------");
System.out.println("Solved!");
}
else
{
System.out.println("\n---------------------------");
System.out.println("Sorry you didn't find the mystery word!");
System.out.println("It was \"" + word + "\"");
}
}
public static String RandomWord(String word)
{
//List of words
Random r = new Random();
int a = 1 + r.nextInt(5);
if(a == 1)
{
word=("Peace");
}
if(a == 2)
{
word=("Nuts");
}
if(a == 3)
{
word=("Cool");
}
if(a == 4)
{
word=("Fizz");
}
if(a == 5)
{
word=("Awesome");
}
return (word);
}
}
Ok, so this is my code for a hangman game, the only thing I have left to do is to get my program to randomize one of the words, which it should do in the method successfully. But the only problem I'm having is getting the String variable "word" to go back to the main class (there are errors underlining all the "word" variables in the main class).
If I could get help with either this or another way to produce a random word from a list, that would be amazing.
In java, parameters are passed by value and not by reference. Therefore, you cannot change the reference of a parameter.
In your case, you need to do:
public static String getRandomWord() {
switch(new Random().nextInt(5)) {
case 0:
return "Peace";
case 1:
return "Nuts";
// ...
default:
throw new IllegalStateException("Something went wrong!");
}
}
And in main:
// ...
String word = getRandomWord();
int len = word.length();
// ...
You can't modify the caller's reference.
RandomWord(word);
needs to be something like
word = RandomWord(word);
Also, by convention, Java methods start with a lower case letter. And, you could return the word without passing one in as an argument and I suggest you save your Random reference and use an array like
private static Random rand = new Random();
public static String randomWord() {
String[] words = { "Peace", "Nuts", "Cool", "Fizz", "Awesome" };
return words[rand.nextInt(words.length)];
}
And then call it like
word = randomWord();

NumberFormatException: For input string: "[memorylocation" java

I'm doing an assignment where the goal is to, among other things, to add two large integers. Here is my code, spread out into four files.
Main that we cannot change:
import java.util.*;
import MyUtils.MyUtil;
public class CSCD210HW7
{
public static void main(String [] args)throws Exception
{
int choice;
String num;
LargeInt one, two, three = null;
Scanner kb = new Scanner(System.in);
num = HW7Methods.readNum(kb);
one = new LargeInt(num);
num = HW7Methods.readNum(kb);
two = new LargeInt(num);
do
{
choice = MyUtil.menu(kb);
switch(choice)
{
case 1: System.out.println(one + "\n");
break;
case 2: System.out.println("The value of the LargeInt is: " + two.getValue() + "\n");
break;
case 3: num = HW7Methods.readNum(kb);
one.setValue(num);
break;
case 4: if(one.equals(two))
System.out.println("The LargeInts are equal");
else
System.out.println("The LargeInts are NOT equal");
break;
case 5: three = two.add(one);
System.out.printf("The results of %s added to %s is %s\n", one.getValue(), two.getValue(), three.getValue());
break;
case 6: HW7Methods.displayAscendingOrder(one, two, three);
break;
default: if(two.compareTo(one) < 0)
System.out.printf("LargeInt %s is less than LargeInt %s\n", two.getValue(), one.getValue());
else if(two.compareTo(one) > 0)
System.out.printf("LargeInt %s is greater than LargeInt %s\n", two.getValue(), one.getValue());
else
System.out.printf("LargeInt %s is equal to LargeInt %s\n", two.getValue(), one.getValue());
break;
}// end switch
}while(choice != 8);
}// end main
}// end class
LargeInt Class(Custom Class We Created)
public class LargeInt implements Comparable<LargeInt>
{
private int[]myArray;
private LargeInt()
{
this("0");
}
public LargeInt(final String str)
{
this.myArray = new int[str.length()];
for(int x = 0; x < this.myArray.length; x++)
{
this.myArray[x] = Integer.parseInt(str.charAt(x)+ "");
}
}
public LargeInt add(final LargeInt passedIn)
{
String stringOne = myArray.toString();
String stringTwo = passedIn.myArray.toString();
int r = Integer.parseInt(stringOne);
int e = Integer.parseInt(stringTwo);
int s = r + e;
return new LargeInt(""+s);
}
public void setValue(final String arrayString)
{
this.myArray = new int[arrayString.length()];
for(int x = 0; x < myArray.length; x++)
{
this.myArray[x]=arrayString.charAt(x);
}
}
#Override
public int compareTo(LargeInt passedIn)
{
if(passedIn == null)
{
throw new RuntimeException("NullExceptionError");
}
int ewu = 0;
int avs = 0;
if(this.myArray.length != passedIn.myArray.length)
{
return this.myArray.length - passedIn.myArray.length;
}
for(int i = 0; i < this.myArray.length -1; i++)
{
if(this.myArray[i] != passedIn.myArray[i])
{
return this.myArray[i]-passedIn.myArray[i];
}
}
return ewu-avs;
}
public int hashCode()
{
String p = "";
for(int f = 0; f < this.myArray.length; f++)
{
p += myArray[f];
}
return p.hashCode();
}
public String getValue()
{
String h = "";
for(int t = 0; t < this.myArray.length; t++)
{
h += myArray[t];
}
return h;
}
#Override
public boolean equals(Object jbo)
{
if(jbo == null)
{
return false;
}
if(!(jbo instanceof LargeInt))
{
return false;
}
LargeInt k =(LargeInt)jbo;
if(k.myArray.length != this.myArray.length)
{
return false;
}
for(int d = 0; d < this.myArray.length; d++)
{
if(k.myArray[d] != myArray[d])
{
return false;
}
}
return true;
}
#Override
public String toString()
{
String c = "";
for(int q = 0; q < this.myArray.length; q++)
{
c += myArray[q];
}
return "The LargeInt is: " + c;
}
}
HW7Methods File
import java.util.*;
import java.io.*;
public class HW7Methods
{
public static String readNum(Scanner kb)
{
String num = "";
System.out.print("Enter Your Large Int: ");
num = kb.nextLine();
return num;
}
public static void displayAscendingOrder(final LargeInt first, final LargeInt second, final LargeInt third)
{
String highestInt;
if(first.compareTo(second) >= 0 && first.compareTo(third) >= 0)
{
highestInt = first.getValue();
}
else if(second.compareTo(first) >= 0 && second.compareTo(third) >= 0)
{
highestInt = second.getValue();
}
else
{
highestInt = third.getValue();
}
String middleInt;
if(first.compareTo(second) >= 0 && first.compareTo(third) <= 0)
{
middleInt = first.getValue();
}
else if(second.compareTo(first) >= 0 && second.compareTo(third) <= 0)
{
middleInt = second.getValue();
}
else
{
middleInt = third.getValue();
}
String lowestInt;
if(first.compareTo(second) <= 0 && first.compareTo(third) <= 0)
{
lowestInt = first.getValue();
}
else if(second.compareTo(first) <= 0 && second.compareTo(third) <= 0)
{
lowestInt = second.getValue();
}
else
{
lowestInt = third.getValue();
}
System.out.println("The LargeInts in order are: " + lowestInt + ", " + middleInt + ", " + highestInt);
}
}
MyUtil file
package MyUtils;
import java.io.*;
import java.util.Scanner;
public class MyUtil
{
public static int menu(Scanner kb)
{
int userChoice;
System.out.println("1) Print First Int");
System.out.println("2) Print Second Int");
System.out.println("3) Add Different Int");
System.out.println("4) Check If Equal");
System.out.println("5) Add Large Ints");
System.out.println("6) Display In Ascending Order");
System.out.println("7) Compare Ints");
System.out.println("8) Quit");
kb = new Scanner(System.in);
System.out.print("Please Select Your Choice: ");
userChoice = kb.nextInt();
while(userChoice < 1 || userChoice > 8)
{
System.out.print("Invalid Menu Choice. Please Re-Enter: ");
userChoice = kb.nextInt();
}
return userChoice;
}
}
When I go to run this code, it prompts me for two Large Integers like it's supposed to. However, when I choose option 5 to add them, this is what I get:
Exception in thread "main" java.lang.NumberFormatException: For input string: "[I#55f96302"
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:580)
at java.lang.Integer.parseInt(Integer.java:615)
at LargeInt.add(LargeInt.java:24)
at CSCD210HW7.main(CSCD210HW7.java:41)
I've never seen that type of error before. Can someone tell me what is going on?
For input string: "[I#55f96302
That is not a "proper" String you are trying to parse here.
This is what an int[] looks like when you call toString() on it.
String stringOne = myArray.toString();
Why do you do that? What is that supposed to do?
int r = Integer.parseInt(stringOne);
int e = Integer.parseInt(stringTwo);
int s = r + e;
From the looks of it, you try to handle "large" ints with your LargeInt class by somehow storing them in an array of ints. That's okay, BigInteger also works like that (more or less), but you cannot just do calculations by trying to convert back to int (after all those numbers are too big for int arithmetic to handle, even if you do the string parsing properly).

why is indexof not working?

I have a program for a hangman game and the indexof is not working for me? its on line 30. I have been trying to figure it out but I cannot.if (guessedWord.indexOf(letter) >= 0). I will keep trying to find out what I did wrong
import java.io.PrintStream;
import java.util.Scanner;
public class Hangman
{
public static void main(String[] args)
{
String[] words = { "write", "program", "that", "receive", "positive" };
Scanner input = new Scanner(System.in);
char anotherGame;
do
{
int index = (int)(Math.random() * words.length);
String hiddenWord = words[index];
StringBuilder guessedWord = new StringBuilder();
for (int i = 0; i < hiddenWord.length(); i++) {
guessedWord.append('*');
}
int numberOfCorrectLettersGuessed = 0; int numberOfMisses = 0;
while (numberOfCorrectLettersGuessed < hiddenWord.length()) {
System.out.print("(Guess) Enter a letter in word " + guessedWord +
" > ");
String s = input.nextLine();
char letter = s.charAt(0);
if (guessedWord.indexOf(letter) >= 0) {
System.out.println("\t" + letter + " is already in the word");
} else if (hiddenWord.indexOf(letter) < 0) {
System.out.println("\t" + letter + " is not in the word");
numberOfMisses++;
} else {
int k = hiddenWord.indexOf(letter);
while (k >= 0) {
guessedWord.setCharAt(k, letter);
numberOfCorrectLettersGuessed++;
k = hiddenWord.indexOf(letter, k + 1);
}
}
}
System.out.println("The word is " + hiddenWord + ". You missed " + numberOfMisses + (numberOfMisses <= 1 ? " time" : " times"));
System.out.print("Do you want to guess for another word? Enter y or n> ");
anotherGame = input.nextLine().charAt(0);
}while (anotherGame == 'y');
}
}
You are passing in a char where String is expected. Try using String.valueOf(letter) like this:
if (guessedWord.indexOf(String.valueOf(letter)) >= 0) {
// Your code
}
StringBuilder#indexOf(char) is undefined. You could do
if (guessedWord.indexOf(Character.toString(letter)) >= 0) {
there's no indexOf(char) method for a StringBuilder.
guessedWord.indexOf(letter)
should be
if (guessedWord.toString().indexOf(letter) >= 0) {

beginner lexical analyzer in java

I am writing a lexical analyzer. I know it's super simple. It runs but whenever enter an input, the program treats it as invalid characters (even when they are supposed to be valid). What did I do wrong?
import java.util.*;
import java.util.Scanner;
public class LAnalyze{
public static int i;
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
String s;
System.out.println("Input something to lexically analyze: ");
s = input.next( );
int j = 1;
if( s.charAt(i)!='a'||s.charAt(i)!='b'||s.charAt(i)!='c'||s.charAt(i)!='d'||s.charAt(i)!='e'||s.charAt(i)!='f'||
s.charAt(i)!='g'||s.charAt(i)!='h'||s.charAt(i)!='i'||s.charAt(i)!='j'||s.charAt(i)!='k'||s.charAt(i)!='l'||
s.charAt(i)!='m'||s.charAt(i)!='n'||s.charAt(i)!='o'||s.charAt(i)!='p'||s.charAt(i)!='q'||s.charAt(i)!='r'||
s.charAt(i)!='s'||s.charAt(i)!='t'||s.charAt(i)!='u'||s.charAt(i)!='v'||s.charAt(i)!='w'||s.charAt(i)!='x'||
s.charAt(i)!='y'||s.charAt(i)!='z'||s.charAt(i)!='A'||s.charAt(i)!='B'||s.charAt(i)!='C'||s.charAt(i)!='D'||
s.charAt(i)!='E'||s.charAt(i)!='F'||s.charAt(i)!='G'||s.charAt(i)!='H'||s.charAt(i)!='I'||s.charAt(i)!='J'||
s.charAt(i)!='K'||s.charAt(i)!='L'||s.charAt(i)!='M'||s.charAt(i)!='N'||s.charAt(i)!='O'||s.charAt(i)!='P'||
s.charAt(i)!='Q'||s.charAt(i)!='R'||s.charAt(i)!='S'||s.charAt(i)!='T'||s.charAt(i)!='U'||s.charAt(i)!='V'||
s.charAt(i)!='W'||s.charAt(i)!='X'||s.charAt(i)!='Y'||s.charAt(i)!='Z'||s.charAt(i)!='0'||s.charAt(i)!='1'||
s.charAt(i)!='2'||s.charAt(i)!='3'||s.charAt(i)!='4'||s.charAt(i)!='5'||s.charAt(i)!='6'||s.charAt(i)!='7'||
s.charAt(i)!='8'||s.charAt(i)!='9'||s.charAt(i)!='-'||s.charAt(i)!='_'||s.charAt(i)!=' ') {
for (int i = 0; i < s.length(); i++) {
System.out.println("Token " + j + " = " + (s.charAt(i)));
j++;
}
}
else {
System.out.println("Invalid character(s) entered.. Program terminated!\n");
System.exit(0);
}
}
}
It would seem that it is impossible to get the results you say you are getting from this code. Your if statement is wrong. As it currently stands, it will always be true. A character will always be not equal to some character or not equal to another character. All of the != should be ==. I would also print out the bad character in the else part that reports it:
System.out.println("bad character " + s.charAt(i) +
" decimal value: " + (int) s.charAt(i));
Scanner does lexing on its own, that is, it returns tokens, not the whole string. I think you should use Console and get everything that was typed:
Console console = System.console();
s = console.readLine("Input something to lexically analyze: ");
import java.util.*;
public class Main {
static int i;
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
String s = "";
while (true) {
System.out.println("Input something to lexically analyze: ");
s = input.nextLine();
analize(s);
}
}
public static void analize(String s) {
String t = "-1234567890_ abcdefjhijklmnopqrstuvwxyzABCDEFJHIJKLMNOPQRSTUVWXYZ";
char[] tt = t.toCharArray();
char[] cc = s.toCharArray();
int z = 1, i = 0, j = 0;
for (i = 0; i < cc.length; i++) {
for (j = 0; j < tt.length; j++) {
if (cc[i] == tt[j]) {
System.out.println("Token " + z + " = '" + cc[i] + "'");
z++;
break;
}
}
if (j > tt.length - 1) {
System.out.println("Invalid character " + (i + 1) + " ('" + cc[i] + "') entered...");
}
}
}
}

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