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Having issue with getting my file to print to console

I have a data structure assignment were the code has to read the text data from a text file and print it onto the screen. The code that I wrote says that the build was a success but the text file itself doesn't print. What do I do?
import java.util.Scanner;
import java.io.IOException;
import java.io.FileInputStream
public class readFile{
public static void main(String[] args) throws IOException {
FileInputStream fileByteStream = null;
Scanner file = null;
int textFile;
try{
fileByteStream = new FileInputStream("file1.txt");
file = new Scanner(fileByteStream);
while(file.hasNextInt()){
textFile = file.nextInt();
System.out.println("file1.txt");
}
}
catch(IOException e){
}
}
}

Replace System.out.println("file1.txt"); by System.out.println(textFile);.

This should work if you have the "file1.txt" saved in the correct location. As is, you are just passing the String "file1.txt" rather than the file object which was not yet created. (See line 13 of this code below)
import java.util.Scanner;
import java.io.IOException;
import java.io.File;
import java.io.FileInputStream;
public class readFile
{
public static void main(String[] args) throws IOException
{
FileInputStream fileByteStream = null;
Scanner file = null;
int textFile;
File file1 = new File("file1.txt");
try
{
fileByteStream = new FileInputStream(file1);
file = new Scanner(fileByteStream);
System.out.println("Reading file...");
while(file.hasNextInt())
{
textFile = file.nextInt();
System.out.println(textFile);
System.out.println("Scanning a line..");
}
file.close();
}
catch(IOException e)
{
System.out.println("Exception handled");
e.printStackTrace();
}
}
}

You can use print statements to help see where the code is breaking. It looks like you have an IO Exception (input/output). Also, you should want to close the Scanner object.
import java.util.Scanner;
import java.io.IOException;
import java.io.FileInputStream;
public class readFile
{
public static void main(String[] args) throws IOException
{
FileInputStream fileByteStream = null;
Scanner file = null;
int textFile;
try
{
fileByteStream = new FileInputStream("file1.txt");
file = new Scanner(fileByteStream);
System.out.println("Reading file...");
while(file.hasNextInt())
{
textFile = file.nextInt();
System.out.println(textFile);
System.out.println("Scanning a line..");
}
file.close();
}
catch(IOException e)
{
System.out.println("Exception handled");
}
}
}

Writing to file in recursion java

So i want my program to write all files containing ".txt" to "out.txt". But wr.close() ends my writer and it only writes the files from one folder and not from all. Need help.
import java.io.*;
public class Prv {
public static void main(String[] args) throws InterruptedException, IOException{
String a=".";
String b="D:\\JavaProjects\\Auditoriski\\.\\Out.txt";
Pomini(a,b);
}
public static void Pomini(String in, String out) throws IOException {
File file = new File(in);
BufferedWriter wr = new BufferedWriter(new FileWriter(out));
if(file.exists()) {
File[] subfiles = file.listFiles();
for(File f : subfiles) {
if(f.isDirectory()) {
Pomini(f.getAbsolutePath(), out );
}
if(f.getName().contains(".txt")) {
System.out.print(f.getName());
System.out.println();
wr.write(f.getName());
wr.newLine();
}
}
}
wr.close();
}
}

You just need to create BufferedWriter and close it outside of your Pomini method and pass it as a parameter.
try (BufferedWriter wr = new BufferedWriter(new FileWriter(out));) {
Pomini(a, b, wr);
}
public static void Pomini(String in, String out, BufferedWriter wr) throws IOException {
File file = new File(in);
if(file.exists()) {
File[] subfiles = file.listFiles();
for(File f : subfiles) {
if(f.isDirectory()) {
Pomini(f.getAbsolutePath(), out, wr);
}
if(f.getName().contains(".txt")) {
System.out.print(f.getName());
System.out.println();
wr.write(f.getName());
wr.newLine();
}
}
}
}

I need help reading data from all files in a directory

I have a piece of code that iterates over all the files in a directory.
But I am stuck now at reading the content of the file into a String object.
public String filemethod(){
if (path.isDirectory()) {
files = path.list();
String[] ss;
for (int i = 0; i < files.length; i++) {
ss = files[i].split("\\.");
if (files[i].endsWith("txt"))
System.out.println(files[i]);
}
}
return String.valueOf(files);
}

Faced with a similar problem and wrote a code a while back. This will read the content of all files of a directory.
May require adjustments based on your file directories but its tried and tested code.Hope this helps :)
package FileHandling;
import java.io.*;
import java.util.ArrayList;
import java.util.Collections;
public class BufferedInputStreamExample {
FileInputStream fis = null;
BufferedInputStream bis = null;
DataInputStream dis = null;
public void readFile(File folder) {
ArrayList<File> myFiles = listFilesForFolder(folder);
for (File f : myFiles) {
String path = f.getAbsolutePath();
//Path of the file(Optional-You can know which file's content is being printed)
System.out.println(path);
File infile = new File(path);
try {
fis = new FileInputStream(infile);
bis = new BufferedInputStream(fis);
dis = new DataInputStream(bis);
while (dis.available() != 0) {
String line = dis.readLine();
System.out.println(line);
}
} catch (IOException e) {
} finally {
try {
fis.close();
bis.close();
dis.close();
} catch (Exception ex) {
}
}
}
}
public ArrayList<File> listFilesForFolder(final File folder){
ArrayList<File> myFiles = new ArrayList<File>();
for (File fileEntry : folder.listFiles()) {
if (fileEntry.isDirectory()) {
myFiles.addAll(listFilesForFolder(fileEntry));
} else {
myFiles.add(fileEntry);
}
}
return myFiles;
}
}
Main method
package FileHandling;
import java.io.File;
public class Main {
public static void main(String args[]) {
//Your directory here
final File folder = new File("C:\\Users\\IB\\Documents\\NetBeansProjects\\JavaIO\\files");
BufferedInputStreamExample bse = new BufferedInputStreamExample();
bse.readFile(folder);
}
}

I would use following code:
public static Collection<File> allFilesInDirectory(File root) {
Set<File> retval = new HashSet<>();
Stack<File> todo = new Stack<>();
todo.push(root);
while (!todo.isEmpty()) {
File tmp = todo.pop();
if (tmp.isDirectory()) {
for (File child : tmp.listFiles())
todo.push(child);
} else {
if (isRelevantFile(tmp))
retval.add(tmp);
}
}
return retval;
}
All you need then is a method that defines what files are relevant for your usecase (for instance txt)
public static boolean isRelevantFile(File tmp) {
// get the extension
String ext = tmp.getName().contains(".") ? tmp.getName().substring(tmp.getName().lastIndexOf('.') + 1) : "";
return ext.equalsIgnoreCase("txt");
}
Once you have all the files, you can easily get all the text with a little hack in Scanner
public static String allText(File f){
// \\z is a virtual delimiter that marks end of file/string
return new Scanner(f).useDelimiter("\\z").next();
}
So now, using these methods you can easily extract all the text from an entire directory.
public static void main(String[] args){
File rootDir = new File(System.getProperty("user.home"));
String tmp = "";
for(File f : allFilesInDirectory(rootDir)){
tmp += allText(f);
}
System.out.println(tmp);
}

import java.io.File;
import java.io.FilenameFilter;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
public class ReadDataFromFiles {
static final File DIRECTORY = new File("C:\\myDirectory");
public static void main(String[] args) throws IOException {
StringBuilder sb = new StringBuilder();
//append content of each file to sb
for(File f : getTextFiles(DIRECTORY)){
sb.append(readFile(f)).append("\n");
}
System.out.println(sb.toString());
}
// get all txt files from the directory
static File[] getTextFiles(File dir){
FilenameFilter textFilter = (File f, String name) -> name.toLowerCase().endsWith(".txt");
return dir.listFiles(textFilter);
}
// read the content of a file to string
static String readFile(File file) throws IOException{
return new String(Files.readAllBytes(Paths.get(file.getAbsolutePath())), StandardCharsets.UTF_8);
}
}

bufferedwritter writing weird foreign characters?

I'm writing a little program that just takes a file, and trims the last 4 characters after a space and writes those to a new file. When I tell it to do this and then print them to console it works fine. They show up fine and everything works. But when I use the BufferedWriter to write it to a new file it gives me a weird string of characters in that file when I check it. Here is my code:
package trimmer;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;
public class trimmer {
private File file;
private File newfile;
private Scanner in;
public void Create() {
String temp, temp1;
try {
setScanner(new Scanner(file));
} catch (FileNotFoundException e) {
System.out.println("file not found!!");
}
if (!newfile.exists()) {
try {
newfile.createNewFile();
FileWriter fw = new FileWriter(newfile.getAbsoluteFile());
BufferedWriter bw = new BufferedWriter(fw);
while (in.hasNextLine()) {
temp1 = in.nextLine();
temp = temp1.substring(temp1.lastIndexOf(' ') + 1);
System.out.println(temp);
bw.write(temp);
}
bw.close();
System.out.println("done!");
} catch (IOException e) {
System.out.println("Could not make new file: " + newfile + " Error code: " + e.getMessage());
}
}
}
public Scanner getScanner() {
return in;
}
public void setScanner(Scanner in) {
this.in = in;
}
public File getFile() {
return file;
}
public void setFile(File file) {
this.file = file;
}
public File getNewfile() {
return newfile;
}
public void setNewfile(File newfile) {
this.newfile = newfile;
}
}
and when I check the file it looks like this:
䐳噔吳商吳啍唳噎吳剄唳剄䘳剄唳噎吳商䠳卉䌳䕎䜳䱁䠳卉䴳㉕倳乓䐳䍐䐳啐吳䍖吳乓吳啍䔳䥘䌳噔匳剕唳乓唳䅍䌳䕎䜳䱁䴳㉕倳乓䐳䍐䐳啐吳䍖䠳卉吳乓吳啍䔳䥘䌳噔匳剕唳乓唳䅍
Can anyone tell me why this would be happening?

FileWriter uses the platform default character encoding. If this is not the encoding that you want, then you need to use an OutputStreamWriter with the appropriately chosen character encoding.

ArrayList Menu Java

I need to make a menu that list the .txt files in a directory. For example, if i have jonsmith12.txt , lenovo123.txt , dell123.txt in the directory how would I make an arraylist menu of:
Please choose one of the following:
jonsmith12
lenovo123
dell123
Please enter your choice:
I need an arraylist menu is because I don't know how many .txt files are in the directory at any given time.
import java.io.File;
public class ListFiles
{
public static void listRecord() {
// Directory path here
String path = ".";
String files;
File folder = new File(path);
File[] listOfFiles = folder.listFiles();
for (int i = 0; i < listOfFiles.length; i++)
{
if (listOfFiles[i].isFile())
{
files = listOfFiles[i].getName();
if (files.endsWith(".txt") || files.endsWith(".TXT"))
{
System.out.println(files);
}
}
}
}
}
Here is the class that will display the information in the .txt file onto the console. It stills need some modifying too but I could probably figure that out.
import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
/**
* This program reads a text file line by line and print to the console. It uses
* FileOutputStream to read the file.
*
*/
public class DisplayRec {
public static void displayRecord() throws IOException {
File file = new File("williamguo5.txt");
FileInputStream fis = null;
BufferedInputStream bis = null;
DataInputStream dis = null;
try {
fis = new FileInputStream(file);
// Here BufferedInputStream is added for fast reading.
bis = new BufferedInputStream(fis);
dis = new DataInputStream(bis);
// dis.available() returns 0 if the file does not have more lines.
while (dis.available() != 0) {
// this statement reads the line from the file and print it to
// the console.
System.out.println(dis.readLine());
}
// dispose all the resources after using them.
fis.close();
bis.close();
dis.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
So the question is: How do I implement a ArrayList menu into my ListFiles class so it will display the .txt files.

You can use the alternate method signature for File.listFiles(FilenameFilter filter) to simplify your code:
File[] files = dir.listFiles(new FilenameFilter() {
#Override
public boolean accept(File dir, String name) {
return name.toLowerCase().endsWith(".txt");
}
});
And unless you really enjoy writing loops, you don't even need to manually loop over the array to convert it to a List:
List<File> lstRecords = Arrays.asList(files);
Your displayRecord method was pretty close; you just needed to pass the file as an argument and use that instead of a hard-coded filename, and you needed to initialize dis.
Putting it all together:
package com.example.file;
import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FilenameFilter;
import java.io.IOException;
import java.util.Arrays;
import java.util.List;
public class FileExample {
public static List<File> listRecords(File dir) {
File[] files = dir.listFiles(new FilenameFilter() {
#Override
public boolean accept(File dir, String name) {
return name.toLowerCase().endsWith(".txt");
}
});
return Arrays.asList(files);
}
public static void displayRecord(File file) {
FileInputStream fis = null;
BufferedInputStream bis = null;
DataInputStream dis = null;
try {
fis = new FileInputStream(file);
// Here BufferedInputStream is added for fast reading.
bis = new BufferedInputStream(fis);
dis = new DataInputStream(bis);
String line = dis.readLine();
while (line != null) {
// this statement reads the line from the file and print it to
// the console.
System.out.println(line);
line = dis.readLine();
}
// dispose all the resources after using them.
fis.close();
bis.close();
dis.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* #param args
*/
public static void main(String[] args) {
List<File> lstRecords = listRecords(new File("."));
for (File record : lstRecords) {
displayRecord(record);
}
}
}
It's also better to use Reader/Writer instead of InputStream/OutputStream if you're working with text files, and you should close your files in the finally block to avoid a potential resource leak.
You'll also notice I didn't explicitly use an ArrayList. In most cases, it's better to program against the interface (in this case, List) as much as possible, and only declare variables using the implementing class when you need to use a method that's only available to that class.

It looks like your sticking point above is the array. If you just need to iterate over the files in a directory, something as simple as the following will do the trick.
import java.io.File;
public class TxtEnumerator {
public static void main(String[] args) {
TxtEnumerator te = new TxtEnumerator();
te.listFiles();
}
public void listFiles() {
String filepath = "." + File.separator + "textDirectory";
File file = new File(filepath);
if (file.isDirectory()) {
for (File f : file.listFiles()) {
if (f.getName().endsWith(".txt")) {
System.out.println(f.getName());
}
}
}
}
}