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Reading a text file from implementation

I am trying to create an implementation that reads a file that the user has typed and submitted. The code for that is located in the SetTester class (shown below). In my implementation I already have an array declared called String[] myArray = new String [] {}; to hold the data from the file. How would I be able to take the file that is being called in the tester class and put it into that array?
public class SetTester
{
public static void main(String [] args) {
StringSet words = new MyStringSet();
Scanner file = null;
FileInputStream fs = null;
String input;
Scanner kb = new Scanner(System.in);
int wordCt = 0;
boolean ok = false;
while (!ok)
{
System.out.print("Enter name of input file: ");
input = kb.nextLine();
try
{
fs = new FileInputStream(input);
ok = true;
}
catch (FileNotFoundException e)
{
System.out.println(input + " is not a valid file. Try again.");
}
}
file = new Scanner(fs);
while (file.hasNext())
{
input = file.next();
words.insert(input);
System.out.println("Current capacity: " + words.getCapacity());
wordCt++;
}
System.out.println("There were " + wordCt + " words in the file");
System.out.println("There are " + words.inventory() + " elements in the set");
System.out.println("Enter a value to remove from the set: ");
input = kb.nextLine();
while (!words.contains(input))
{
System.out.println(input + " is not in the set");
System.out.println("Enter a value to remove from the set: ");
input = kb.nextLine();
}
words.remove(input);
System.out.println("There are now " + words.inventory() + " elements in the set");
System.out.println("The first 10 words in the set are: ");
for (int x=0; x<10; x++)
System.out.println(words.getFirstItem());
System.out.println("There are now " + words.inventory() + " elements in the set");
System.out.println("5 random words from the set are: ");
for (int x=0; x<5; x++)
System.out.println(words.getRandomItem());
System.out.println("There are now " + words.inventory() + " elements in the set");
}
}

For reading from a file I use this class:
import java.io.IOException;
import java.io.FileReader;
import java.io.BufferedReader;
public class ReadFile {
private static String path;
public ReadFile(String file_path){
path = file_path;
}
public String[] OpenFile() throws IOException {
FileReader fr = new FileReader(path);
BufferedReader textReader = new BufferedReader(fr);
int numberOfLines = readLines();
String[] textData = new String[numberOfLines];
for (int j = 0; j < numberOfLines; j++) {
textData[j] = textReader.readLine();
}
textReader.close();
return textData;
}
static int readLines() throws IOException {
FileReader file_to_read = new FileReader(path);
BufferedReader bf = new BufferedReader(file_to_read);
String aLine;
int numberOfLines = 0;
while((aLine = bf.readLine()) != null){
numberOfLines++;
}
bf.close();
return numberOfLines;
}
}
then in the class main you can add this code and you edit the path so you can read a file an get an array out of it
public static void main(String args[]) throws IOException {
ReadFile r = new ReadFile("here you put the path that the user provide");
String[] text = r.OpenFile();
ArrayList<String> array = new ArrayList<>();
array.addAll(Arrays.asList(text));
}
If you have any questions let me know!

Having trouble with file output

I want to be able to read in 20 random names from the file and put them into a new file. How do i go about this?
public class Assignment2 {
public static void main(String[] args) throws IOException
{
// Read in the file into a list of strings
BufferedReader reader = new BufferedReader(new FileReader("textfile.txt"));
//BufferedWriter bw = new BufferedWriter(new FileWriter("out.txt"));
List<String> lines = new ArrayList<String>();
String line = reader.readLine();
while( line != null ) {
lines.add(line);
line = reader.readLine();
}
// Choose a random one from the list
Random r = new Random();
for (int i = 0; i < 20; i++)
{
int rowNum = r.nextInt(lines.size ());
System.out.println(lines.get(rowNum));
}
}
}

try (BufferedWriter writer = new BufferedWriter(new FileWriter("randomNames.txt"))) {
Random random = new Random();
for (int i = 0; i < 20; i++) {
int rowNum = random.nextInt(lines.size());
writer.write(lines.get(rowNum));
writer.newLine();
}
}
If you need to check if some number was already used, add it to a set:
try (BufferedWriter writer = new BufferedWriter(new FileWriter("randomNames.txt"))) {
Set<Integer> usedNumbers = new HashSet<Integer>(20);
Random random = new Random();
int addedCount = 0;
while (addedCount < 20) {
int rowNum = random.nextInt(lines.size());
if (usedNumbers.add(rowNum)) {
writer.write(lines.get(rowNum));
writer.newLine();
addedCount++;
}
}
}
To check if there is another name with same first character:
private static void containsNameWithSameFirstCharacter(Collection<String> names, String name) {
for (String anotherName : names) {
if (anotherName.charAt(0) == name.charAt(0)) {
return true;
}
}
return false;
}
Then you do:
Random random = new Random();
Set<String> usedNames = new HashSet<String>(20);
while (usedNames.size() < 20) {
int rowNum = random.nextInt(lines.size());
String name = lines.get(rowNum);
if (!containsNameWithSameFirstCharacter(usedNames, name)) {
usedNames.add(name);
writer.write(name);
writer.newLine();
}
}

Getting file input from two source files

I am trying to write a program that merges two arrays from numbers that are in two different text files into a third array.
I have the method done to merge the two arrays into the third array.
But I don't know how to get the numbers from the second file.
Here is my current code :
public static void main(String[] args) {
int[] mergedArray = {};
Scanner input = new Scanner(System.in);
System.out.println("Enter the name of your first file (including file extension): ");
String filename = input.next();
int[] firstArray;
try (Scanner in = new Scanner(new File(filename)))
{
int count = in.nextInt();
firstArray = new int[count];
firstArray[0] = count;
for (int i = 0; in.hasNextInt() && count != -1 && i < count; i++) {
firstArray[i] = in.nextInt();
}
} catch (final FileNotFoundException e) {
System.out.println("That file was not found. Program terminating...");
e.printStackTrace();
}
}
Any help would be appreciated thanks.

If i understood correctly, you just have to create a new Scanner, one for each file.
Like that:
public static void main(String[] args) {
int[] mergedArray = {};
Scanner input = new Scanner(System.in);
System.out.println("Enter the name of your first file (including file extension): ");
String filename1 = input.next();
System.out.println("Enter the name of your second file (including file extension): ");
String filename2 = input.next();
int[] firstArray = null;
int[] secondArray = null;
try {
Scanner in = new Scanner(new File(filename1));
int count = in.nextInt();
firstArray = new int[count];
firstArray[0] = count;
for (int i = 0; in.hasNextInt() && count != -1 && i < count; i++) {
firstArray[i] = in.nextInt();
}
} catch (final FileNotFoundException e) {
System.out.println("That file was not found. Program terminating...");
e.printStackTrace();
}
try {
Scanner in2 = new Scanner(new File(filename2));
int count = in2.nextInt();
secondArray = new int[count];
secondArray[0] = count;
for (int i = 0; in2.hasNextInt() && count != -1 && i < count; i++) {
secondArray[i] = in2.nextInt();
}
} catch (final FileNotFoundException e) {
System.out.println("That file was not found. Program terminating...");
e.printStackTrace();
}
// do the merge operation with the 2 arrays
}

Try this
import java.io.*;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.Files;
import java.nio.file.LinkOption;
import java.util.Scanner;
import static java.lang.System.*;
import java.util.Collection;
import java.util.Collections;
import java.util.ArrayList;
import java.util.Arrays;
public final class TwoSourceMergeOne{
public static void main(String[] args) {
Integer [] mergedArray = null;
try(Scanner console = new Scanner(in)){
out.println("Enter the Source file names (including file extensions) : ");
out.print(">> ");
String sourceX = console.next();
out.print("\n>> ");
String sourceY = console.next();
Path sourceXPath = Paths.get(sourceX);
Path sourceYPath = Paths.get(sourceY);
if(!Files.exists(sourceXPath,LinkOption.NOFOLLOW_LINKS) || !Files.exists(sourceXPath,LinkOption.NOFOLLOW_LINKS)){
out.println("Sorry. Some source files are missing. Please make sure that they are available !");
return;
}
Scanner xInput = new Scanner(new FileInputStream(sourceXPath.toFile()));
Scanner yInput = new Scanner(new FileInputStream(sourceYPath.toFile()));
Collection<Integer> sourceXData = new ArrayList<>();
Collection<Integer> sourceYData = new ArrayList<>();
while(xInput.hasNextInt()) sourceXData.add(xInput.nextInt());
while(yInput.hasNextInt()) sourceYData.add(yInput.nextInt());
if(!sourceXData.isEmpty() && !sourceYData.isEmpty()){
Integer [] soure_x_array = sourceXData.toArray(new Integer[sourceXData.size()]);
Integer [] source_y_array = sourceYData.toArray(new Integer[sourceYData.size()]);
mergedArray = new Integer[soure_x_array.length+source_y_array.length];
int index = 0;
for(int x : soure_x_array) mergedArray[index ++] = x;
for(int y : source_y_array) mergedArray[index ++] = y;
out.printf("The merged array is = %s",Arrays.toString(mergedArray));
}else{
out.println("Sorry. No input data !!!");
}
}catch(IOException cause){ cause.printStackTrace();}
}
}
The two source files should be in the same folder as the program.

Java - store elements of ArrayList into separate blocks

so here is ALL of my code, which, in summary, standardises two text files then prints out the result.
import java.io.*;
import java.util.*;
public class Plagiarism {
public static void main(String[] args) {
Plagiarism myPlag = new Plagiarism();
if (args.length == 0) {
System.out.println("Error: No files input");
}
else if (args.length > 0) {
try {
for (int i = 0; i < args.length; i++) {
BufferedReader reader = new BufferedReader (new FileReader (args[i]));
List<String> foo = simplify(reader);
for (int j = 0; j < foo.size(); j++) {
System.out.print(foo.get(j));
}
}
}
catch (Exception e) {
System.err.println ("Error reading from file");
}
}
}
public static List<String> simplify(BufferedReader input) throws IOException {
String line = null;
List<String> myList = new ArrayList<String>();
while ((line = input.readLine()) != null) {
myList.add(line.replaceAll("[^a-zA-Z0-9]","").toLowerCase().trim());
}
return myList;
}
}
The next bit I want to implement is this: Using the command line, the 3rd argument will be any integer(size of blocks) which the user enters. I have to use this then to store the elements of that array into separate blocks which overlap. EG: The cat sat on the mat, block size 4. Block 1 would be: Thec Block 2: heca Block 3: ecat, and so on, until it reaches the end of the array.
Any ideas?
Thanks in advance guys.

To get the block size use this :
if(args.length != 4)
return;
int blockSize = Integer.valueOf(args[3]);
This an example that could help you
import java.util.*;
public class Test {
public static void main(String[] args) {
String line = "The dog is in the house";
line = line.replace(" ", "");
List<String> list = new ArrayList<String>();
for (int i = 0; i <= line.length() - 4; i++)
list.add(line.substring(i, i + 4));
System.out.println(list);
}
output :
[Thed, hedo, edog, dogi, ogis, gisi, isin, sint, inth, nthe, theh, heho, ehou, hous, ouse]
Is that what you want to do

WE can code it in mulitple ways, here is one example.
Input 3 arguments first 2 are files and 3rd one is the block size:
File1 contain: this is a boy
File2 contain: this is a girl
block size: 4
Expected Output:
this hisi isis sisa isab sabo aboy boyt oyth ythi this hisi isis sisa isag sagi agir girl
Program:
import java.io.;
import java.util.;
public class Plagiarism {
public static void main(String[] args) {
//Plagiarism myPlag = new Plagiarism();
/*args = new String[3];
Scanner s = new Scanner(System.in);
System.out.println("Enter the 1st file path");
args[0] = s.next();
System.out.println("Enter the 2nd file path");
args[1] = s.next();
System.out.println("Enter size of block");
args[2] = s.next();*/
int blockSize = Integer.valueOf(args[2]);
StringBuilder wholeContent = new StringBuilder("");
if (args.length == 0) {
System.out.println("Error: No files input");
}
else if (args.length > 0) {
try {
for (int i = 0; i < args.length-1; i++) {
BufferedReader reader = new BufferedReader (new FileReader (args[i]));
List<String> foo = simplify(reader);
for (int j = 0; j < foo.size(); j++) {
//System.out.print(foo.get(j));
wholeContent.append(foo.get(j));
}
}
System.out.println("The content of Line is = "+ wholeContent);
System.out.println("The content of line based on the block size = "+ blockSize + " is:");
for(int j=0; j<=(wholeContent.length()-blockSize); j++){
System.out.print(wholeContent.substring(j, j+4));
System.out.print(" ");
}
}
catch (Exception e) {
e.printStackTrace();
System.err.println ("Error reading from file");
}
}
}
public static List<String> simplify(BufferedReader input) throws IOException {
String line = null;
List<String> myList = new ArrayList<String>();
while ((line = input.readLine()) != null) {
if(!" ".equals(line))
myList.add(line.replaceAll("[^a-zA-Z0-9]","").toLowerCase().trim());
}
return myList;
}
}

All you are asking to do can be done with string manipulation. First use replaceAll() to remove your spaces, then use a for loop and substring() to create your blocks.
for your for loop you need to modify it so that it reads the two texts, then uses the 3rd argument as the block size so you would change your for loop from:
for(int i = 0; i<args.length;i++)
to:
for(int i = 1; i<3; i++)
this reads the first two arguments but not the third

How do you store each value separately using comma then they store into separate array?

A simple data file which contains
1908,Souths,Easts,Souths,Cumberland,Y,14,12,4000
1909,Souths,Balmain,Souths,Wests,N
Each line represents a season of premiership and has the following format: year, premiers, runners up, minor premiers, wooden spooners, Grand Final held, winning score,
losing score, crowd
I know how to store a data into an array and use the delimiter, but I am not exactly sure how to store EACH data item by a comma into separate arrays? Some suggestions and what particular code to be used would be nice.
UPDATE:
I just added the code but it still didn't work. Here's the code:
import java.io.*;
import java.util.Scanner;
public class GrandFinal {
public static Scanner file;
public static String[] array = new String[1000];
public static void main(String[] args) throws FileNotFoundException {
File myfile = new File("NRLdata.txt");
file = new Scanner (myfile);
Scanner s = file.useDelimiter(",");
int i = 0;
while (s.hasNext()) {
i++;
array[i] = s.next();
}
for(int j=0; j<array.length; j++) {
if(array[j] == null)
;
else if(array[j].contains("Y"))
System.out.println(array[j] + " ");
}
}
}

Here you go. Use ArrayList. Its dynamic and convenient.
BufferedReader br = null;
ArrayList<String> al = new ArrayList();
String line = "";
try {
br = new BufferedReader(new FileReader("NRLdata.txt"));
while ((line = br.readLine()) != null) {
al.add(line);
}
} catch (Exception e) {
e.printStackTrace();
}
for (int i = 0; i < al.size(); i++) {
System.out.println(al.get(i));
}
What does not work in your case ?
Because your season array is empty. You need to define the length, for ex:
private static String[] season = new String[5];
This is not right because you don't know how many lines you are going to store. Which is why I suggested you to Use ArrayList.

After working around a bit, I have come up with following code:
private static File file;
private static BufferedReader counterReader = null;
private static BufferedReader fileReader = null;
public static void main(String[] args) {
try {
file = new File("C:\\Users\\rohitd\\Desktop\\NRLdata.txt");
counterReader = new BufferedReader(new FileReader(file));
int numberOfLine = 0;
String line = null;
try {
while ((line = counterReader.readLine()) != null) {
numberOfLine++;
}
String[][] storeAnswer = new String[9][numberOfLine];
int counter = 0;
fileReader = new BufferedReader(new FileReader(file));
while ((line = fileReader.readLine()) != null) {
String[] temp = line.split(",");
for (int j = 0; j < temp.length; j++) {
storeAnswer[j][counter] = temp[j];
System.out.println(storeAnswer[j][counter]);
}
counter++;
}
} catch (IOException e) {
e.printStackTrace();
}
}
catch (FileNotFoundException e) {
System.out.println("Unable to read file");
}
}
I have added counterReader and fileReader; which are used for counting number of lines and then reading the actual lines. The storeAnswer 2d array contains the information you need.
I hope the answer is better now.