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Writing a program in Java to read in multiple strings from user and compare to text file

I am attempting to write a program that will take user input ( a long message of characters), store the message and search a text file to see if those words occur in the text file. The problem I am having is that I am only ever able to read in the first string of the message and compare it to the text file. For instance if I type in "learning"; a word in the text file, I will get a result showing that is is found in the file. However if I type "learning is" It will still only return learning as a word found in the file even though "is" is also a word in the text file. My program seems to not be able to read past the blank space. So I suppose my questions is, how do I augment my program to do this and read every word in the file? Would it also be possible for my program to read every word, with or without spaces, in the original message taken from the user, and compare that to the text file?
Thank you
import java.io.*;
import java.util.Scanner;
public class Affine_English2
{
public static void main(String[] args) throws IOException
{
String message = "";
String name = "";
Scanner input = new Scanner(System.in);
Scanner scan = new Scanner(System.in);
System.out.println("Please enter in a message: ");
message = scan.next();
Scanner file = new Scanner(new File("example.txt"));
while(file.hasNextLine())
{
String line = file.nextLine();
for(int i = 0; i < message.length(); i++)
{
if(line.indexOf(message) != -1)
{
System.out.println(message + " is an English word ");
break;
}
}
}
}
}

I recommend you first process the file and build a set of legal English words:
public static void main(String[] args) throws IOException {
Set<String> legalEnglishWords = new HashSet<String>();
Scanner file = new Scanner(new File("example.txt"));
while (file.hasNextLine()) {
String line = file.nextLine();
for (String word : line.split(" ")) {
legalEnglishWords.add(word);
}
}
file.close();
Next, get input from the user:
Scanner input = new Scanner(System.in);
System.out.println("Please enter in a message: ");
String message = input.nextLine();
input.close();
Finally, split the user's input to tokens and check each one if it is a legal word:
for (String userToken : message.split(" ")) {
if (legalEnglishWords.contains(userToken)) {
System.out.println(userToken + " is an English word ");
}
}
}
}

You may try with this. With this solution you can find each word entered by the user in your example.txt file:
public static void main(String[] args) throws IOException
{
String message = "";
String name = "";
Scanner input = new Scanner(System.in);
Scanner scan = new Scanner(System.in);
System.out.println("Please enter in a message: ");
message = scan.nextLine();
Scanner file = new Scanner(new File("example.txt"));
while (file.hasNextLine())
{
String line = file.nextLine();
for (String word : message.split(" "))
{
if (line.contains(word))
{
System.out.println(word + " is an English word ");
}
}
}
}

As Mark pointed out in the comment, change
scan.next();
To:
scan.nextLine();
should work, i tried and works for me.

If you can use Java 8 and Streams API
public static void main(String[] args) throws Exception{ // You need to handle this exception
String message = "";
Scanner input = new Scanner(System.in);
System.out.println("Please enter in a message: ");
message = input.nextLine();
List<String> messageParts = Arrays.stream(message.split(" ")).collect(Collectors.toList());
BufferedReader reader = new BufferedReader(new FileReader("example.txt"));
reader.lines()
.filter( line -> !messageParts.contains(line))
.forEach(System.out::println);
}

You have many solution, but when it comes to find matches I suggest you to take a look to the Pattern and Matcher and use Regular Expression
I haven't fully understood your question, but you could do add something like this (I did not tested the code but the idea should work fine):
public static void main(String[] args) throws IOException{
String message = "";
String name = "";
Scanner input = new Scanner(System.in);
Scanner scan = new Scanner(System.in);
System.out.println("Please enter in a message: ");
message = scan.next();
Scanner file = new Scanner(new File("example.txt"));
String pattern = "";
for(String word : input.split(" ")){
pattern += "(\\b" + word + "\\b)";
}
Pattern r = Pattern.compile(pattern);
while(file.hasNextLine())
{
String line = file.nextLine();
Matcher m = r.matcher(line);
if(m.matches()) {
System.out.println("Word found in: " + line);
}
}
}

Asking for a word and checking its number of occurrence in a text file

public class Try{
public static void main (String args[]) throws IOException {
BufferedReader in = new BufferedReader(new FileReader("Try.txt"));
Scanner sc = new Scanner(System.in);
System.out.print("Enter the subtring to look for: ");
String Word=sc.next();
String line=in.readLine();
int count =0;
String s[];
do
{
s=line.split(" ");
for(int i=0; i < s.length; i++)
{
String a = s[i];
if(a.contains(Word))
count++;
}
line=in.readLine();
}while(line!=null);
System.out.print("There are " +count+ " occurences of " +Word+ " in ");
java.io.File file = new java.io.File("Try.txt");
Scanner input = new Scanner(file);
while(input.hasNext())
{
String word = input.nextLine();
System.out.print(word);
}
}
}
The intended purpose of my program is to ask the user for a certain word(s) that will be checked in a text file and if it exists, it will count the number of times the user-entered word occurs in the text file. So far, my program can only search for one word. If I try two words separated by space, only the first word will be searched and counted for its number of occurrence. Any tips on how to search multiple words?

I was following literally the title of the question and therefore I will suggest this algorithm:
public static void main(String[] args) throws IOException {
BufferedReader in = new BufferedReader(new FileReader("Test.txt"));
Scanner sc = new Scanner(System.in);
System.out.print("Enter the subtring to look for: ");
String word = sc.next();
String line = in.readLine();
int count = 0;
// here is where the efficiently magic happens
do {
// 1. you dont need to split a line by spaces, too much overhead...
// 2. and you dont need to do counter++
// 3. do instead: calculate the number of coincidences that the word is
//repeated in a whole line...that is what the line below does..
count += (line.length() - line.replace(word, "").length()) / word.length();
//the rest looks fine
//NOTE: if you need a whole word then wrap the input of the user and add the empty spaces at begin and at the end...so the match will be perfect to a word
line = in.readLine();
} while (line != null);
System.out.print("There are " + count + " occurences of " + word + " in ");
}
Edit:
if you want to check more than one word in the document then use this
public static void main(String[] args) throws IOException {
BufferedReader in = new BufferedReader(new FileReader("Test.txt"));
Scanner sc = new Scanner(System.in);
System.out.print("Enter the subtring to look for: ");
String input = sc.nextLine();
String[] word = input.split(" ");
String line = in.readLine();
int count = 0;
do {
for (String string : word) {
count += (line.length() - line.replace(string, "").length()) / string.length();
}
line = in.readLine();
} while (line != null);
System.out.print("There are " + count + " occurences of " + Arrays.toString(word) + " in ");
}

Using four methods to count and display the lines, words, and characters in a file in java

This is my first time using more than one method in a progam and I have also never tried to count lines, words and letters in a file. So I've read three Java books file sections and then looked at questions on the forum here and had a go. I think I am doing something wrong with variable names, as I don't know the rules with where you put them in in multi method etc. If you could say something like that is glaringly wrong because you have to do this, that would be helpful. I can't use the debugger because I can't compile it. Anyway, thanks for looking at this.
import java.util.Scanner;
import java.io.*;
/**
* A program to count the number of lines, words and characters in a text file.
*
* #author
* #version 2014
*/
public class WordCount
{
public static void main(String[] args) throws FileNotFoundException
{
// get the filename
Scanner keyboard = new Scanner(System.in);
System.out.print("Enter the name of the file: ");
String filename = keyboard.nextLine();
File file = new File(filename);
Scanner inputFile = new Scanner(file);
lines(filename);
words(filename);
characters(filename);
}
/**
* Count the number of lines in a file, and print out the result.
*
*/
public static void lines(String filename) throws FileNotFoundException
{
Scanner inputFile = new Scanner(file);
int lines = 0;
while (inputFile.hasNextLine())
{
lines++;
file.nextLine();
}
return lines;
inputFile.close();
}
/**
* Count the number of words in a file, and print out the result.
*
*/
public static void words(String filename) throws FileNotFoundException
{
Scanner inputFile = new Scanner(file);
int words = 0;
while (input.hasNextLine())
{
String word = input.next();
words++;
}
return words;
inputFile.close();
}
/**
* Count the number of characters in a file, and print out the result.
*
*/
public static void characters(String filename) throws FileNotFoundException
{
Scanner inputFile = new Scanner(file);
int characters = 0;
while (inputFile.hasNextLine())
{
String line = inputFile.nextLine();
for(int i = 0; i < line.length(); i++)
{ characters = line.charAt(i);
if (character != 32)
{
characters++;
}
}
}
return characters;
inputFile.close();
System.out.println("The number of lines is: " + lines);
System.out.println("The number of words is: " + words);
System.out.println("The number of characters is: " + characters);
System.out.println();
}
}

Change the following
public static int lines(String filename) throws FileNotFoundException
//change the return type to int instead of void
{
Scanner inputFile = new Scanner(filename); //filename instead of file
int lines = 0;
while (inputFile.hasNextLine())
{
lines++;
inputFile.nextLine(); // ---do----
}
inputFile.close(); // after return it will become unreachable
return lines;
}
Same applies to other methods

Your code contains several problems. So let us fix that one by one in each method:
public static void main(String[] args) throws FileNotFoundException
{
// get the filename
Scanner keyboard = new Scanner(System.in);
System.out.print("Enter the name of the file: ");
String filename = keyboard.nextLine();
keyboard.close(); // <- don't forget to close this resource
File file = new File(filename);
//Scanner inputFile = new Scanner(file); // <- this line is unnecessary, because you never use that variable
lines(file); // <- you already obtained a File object, so use it ;)
words(file);
characters(file);
}
Next method:
public static void lines(File file) throws FileNotFoundException // mind the new argument type
{
Scanner inputFile = new Scanner(file);
int lines = 0;
while (inputFile.hasNextLine())
{
lines++;
inputFile.nextLine(); //<- use "inputFile" instead of "file"
}
inputFile.close();
//return lines; // <- you can't return something if your method uses "void" as the return type
//your comment on that method says that you like to print the result, so let's do that
System.out.println("The number of lines is: " + lines);
}
And the next one:
public static void words(File file) throws FileNotFoundException // <- new argument type
{
Scanner inputFile = new Scanner(file);
int words = 0;
while (inputFile.hasNextLine())
{
//String word = inputFile.next(); // that won't work like you think, but we can do a little "trick" here
String line = inputFile.nextLine(); // read the current line of text
words += line.split(" ").length; // split the line using whitespace and add the number of words to the current value of variable "words"
//words++; // <- not needed anymore
}
//return words; // <- like before: not possible if return type is void
inputFile.close();
//your comment on that method says that you like to print the result, so let's do that
System.out.println("The number of words is: " + words);
}
And the last method:
public static void characters(File file) throws FileNotFoundException
{
Scanner inputFile = new Scanner(file);
int characters = 0;
int count = 0; // new variable to count the characters
while (inputFile.hasNextLine())
{
String line = inputFile.nextLine();
for(int i = 0; i < line.length(); i++)
{
characters = line.charAt(i); // <- no harm in using a new line :)
if (characters != 32) // <- you wrote "character"
{
count++; // <- "characters" is the current character itself, we won't increase that. For example "a" would become "b" and we don't want/need that :)
}
}
}
//return characters; // <- you know that already ...
inputFile.close();
//System.out.println("The number of lines is: " + lines); // <- "lines" and "words" are unknown here, but we printed these results already
//System.out.println("The number of words is: " + words);
System.out.println("The number of characters is: " + count); // <- print the count of characters
System.out.println();
}
After this changes you code should work now :).

It seems the methods only need the File object.
int n = countLines(file);
System.out.println("Lines: " + n);
...
public static int countLines(File textFile) throws IOException
{
Scanner inputFile = new Scanner(textFile);
int lines = 0
while (inputFile.hasNextLine())
{
lines++;
inputFile.nextLine();
}
inputFile.close();
return lines;
}
For nextLine you asked the wrong object, Scanner needed.
return returns from the method, so close has come before.
As you return the line count, you must return int.
Method names contain a verb by convention.
The method knows no file or filename.
It also cannot alter a variable if you pass a variable, like file,
You can give the new paramaeter the same name, but for clarity not done here.

Problem number 1:
public static void lines(String filename) throws FileNotFoundException
{
Scanner inputFile = new Scanner(file);
int lines = 0;
while (inputFile.hasNextLine())
{
lines++;
file.nextLine();
}
return lines; // <----------------
inputFile.close();
}
This is a void method but you have a return lines statement. Either remove it or change the method header to public static int lines(String filename) throws FileNotFoundException
Problem number 2
public static void words(String filename) throws FileNotFoundException
{
Scanner inputFile = new Scanner(file);
int words = 0;
while (input.hasNextLine())
{
String word = input.next();
words++;
}
return words; <-------------
inputFile.close();
}
Again here you ask from a void method to return a value. Change method header to public static int words(String filename) throws FileNotFoundException
Problem number 3:
public static void characters(String filename) throws FileNotFoundException
{
Scanner inputFile = new Scanner(file);
int characters = 0;
while (inputFile.hasNextLine())
{
String line = inputFile.nextLine();
for(int i = 0; i < line.length(); i++)
{ characters = line.charAt(i);
if (character != 32)
{
characters++;
}
}
}
return characters; //<---------------
inputFile.close();
System.out.println("The number of lines is: " + lines);
System.out.println("The number of words is: " + words);
System.out.println("The number of characters is: " + characters);
System.out.println();
}
Again here you have a return int statement on a void method. Just change the method header to this: public static int characters(String filename) throws FileNotFoundException

big txt file to String? [duplicate]

This question already has answers here:
Reading a plain text file in Java
(31 answers)
Closed 9 years ago.
okay so I know this code isn't entirely orthodox, but regardless it compiles & runs. the problem is once i input a txt file via the command line it only converts the first line in the file into String text. (yes, i know im using the nextLine() method.that is temp until i find a better way). How can i get the entire txt file, that has line breaks, into one string? thanks in advance for any suggestions/ tips.
import java.util.*;
public class Concordance{
static Scanner kb;
public static void main(String arg[]){
//input text file, create array, create List, and call other methods
kb = new Scanner(System.in);
String text = kb.nextLine();
String[] words = text.replaceAll("[^a-zA-Z ]", "").toLowerCase().split("\\s+");
List<String> list = Arrays.asList(text.replaceAll("[^a-zA-Z ]", "").toLowerCase().split("\\s+"));
System.out.println("number of words in text (including duplicates) is: " + words.length);
System.out.println("");
alphaPrint(list);
System.out.println("");
uniqueWord(list);
}//end main
//prints text in alphabetical order and counts unique words
public static void alphaPrint(List<String> list){
int count = 0;
TreeSet<String> uniqueWord = new TreeSet<String>(list);
System.out.println("text in alphabetical order: ");
Collections.sort(list);
for (String word : uniqueWord) {
System.out.println(word);
count++;
}
System.out.println("");
System.out.println("unique word count is: " + count);
}//end alphaprint
//method will find and print frequency counts
public static void uniqueWord(List<String> list){
System.out.println("text with word frequencies: ");
TreeSet<String> uniqueWord = new TreeSet<String>(list);
for (String word : uniqueWord) {
System.out.println(word + ": " + Collections.frequency(list, word));
}
}//end unique word
}//end class

Maybe something like this
StringBuilder s = new StringBuilder();
while(kb.hasNextLine()){
s.append(kb.nextLine())
}
text = s.toString();
Or maybe build the array in the while loop.. using kb.hasNext(pattern)
---- Edit
You can run the the application using ./java filename < textfile.txt

The code must iterate through the supplied file using a loop. Here is an example:
public class FileToString {
public static void main(String[] args) {
System.out.println("Please Enter a File:");
Scanner scanner = new Scanner(System.in);
String fileName = scanner.nextLine();
Scanner fileScanner;
try {
File file = new File(fileName);
fileScanner = new Scanner(file);
String text = "";
while (fileScanner.hasNext()) {
text += fileScanner.nextLine();
}
System.out.println(text);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
}

Java simple counting words in a file

I am creating a simple program that counts the number of words, lines and total characters (not including whitespace) in a paper. It is a very simple program. My file compiles but when I run it I get this error:
Exception in thread "main" java.util.NoSuchElementException
at java.util.Scanner.throwFor(Scanner.java:838)
at java.util.Scanner.next(Scanner.java:1347)
at WordCount.wordCounter(WordCount.java:30)
at WordCount.main(WordCount.java:16)
Does anyone know why this is happening?
import java.util.*;
import java.io.*;
public class WordCount {
//throws the exception
public static void main(String[] args) throws FileNotFoundException {
//calls on each counter method and prints each one
System.out.println("Number of Words: " + wordCounter());
System.out.println("Number of Lines: " + lineCounter());
System.out.println("Number of Characters: " + charCounter());
}
//static method that counts words in the text file
public static int wordCounter() throws FileNotFoundException {
//inputs the text file
Scanner input = new Scanner(new File("words.txt"));
int countWords = 0;
//while there are more lines
while (input.hasNextLine()) {
//goes to each next word
String word = input.next();
//counts each word
countWords++;
}
return countWords;
}
//static method that counts lines in the text file
public static int lineCounter() throws FileNotFoundException {
//inputs the text file
Scanner input2 = new Scanner(new File("words.txt"));
int countLines = 0;
//while there are more lines
while (input2.hasNextLine()) {
//casts each line as a string
String line = input2.nextLine();
//counts each line
countLines++;
}
return countLines;
}
//static method that counts characters in the text file
public static int charCounter() throws FileNotFoundException {
//inputs the text file
Scanner input3 = new Scanner(new File("words.txt"));
int countChar = 0;
int character = 0;
//while there are more lines
while(input3.hasNextLine()) {
//casts each line as a string
String line = input3.nextLine();
//goes through each character of the line
for(int i=0; i < line.length(); i++){
character = line.charAt(i);
//if character is not a space (gets rid of whitespace)
if (character != 32){
//counts each character
countChar++;
}
}
}
return countChar;
}
}

I can't really say the exact reason for the problem without looking at the file (Maybe even not then).
while (input.hasNextLine()) {
//goes to each next word
String word = input.next();
//counts each word
countWords++;
}
Is your problem. If you are using the input.hasNextLine() in the while conditional statement use input.nextLine(). Since you are using input.next() you should use input.hasNext() in the while loops conditional statement.

public static int wordCounter() throws FileNotFoundException
{
Scanner input = new Scanner(new File("words.txt"));
int countWords = 0;
while (input.hasNextLine()) {
if(input.hasNext()) {
String word = input.next();
countWords++;
}
}
return countWords;
}
I have just added an if condition within the while loop. Just make sure to check there are token to be parsed. I have changed only in this place. Just make sure to change wherever needed.
This link will give good info. in regard to that.
Hope it was helpful. :)