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FileNotFoundException for a valid file using FileInputStream

When I write an FileInputStream, while I have the valid file, it throws a FileNotFoundException.
I used this:
package io;
import java.io.*;
public class implementIo {
public static int i;
public static FileOutputStream output;
public static FileInputStream input;
public static void main(String args[]) {
try {
output = new FileOutputStream("writeModification.txt");
input = new FileInputStream("modification.txt");
do {
i = input.read();
if(i != -1) output.write(i);
}while(i != -1);
} catch (Exception e) {
System.out.println("Exception caught " + e);
} finally {
try {
if(output == null) input.close();
}catch(IOException e) {
System.out.println("IOException caught: " + e);
}
}
}
}
While I had a two separate files named "modification.txt" and "printModification.txt" in the same package folder, yet the system threw a FileNotFoundException. Please help!

This is because the FileInputStream doesn't provide the file creation during initialization like new FileOutputStream() does. So if these have been said, we can see one interesting thing to keep in mind: the modification.txt will be created every time when you initialize the FileOutputStream (and won't be overwritten) and this is why most probably your code breaks at the new FileInputStream() line.
How can you handle your exception?
You either create your file before executing the code( manually with New -> Text Document etc. ) or modify your code and make use of File class :
File file = new File("modification.txt");
try {
file.createNewFile();
input = new FileInputStream(file);
//your code here - output etc.
Your code still doesn't work even if you have the files created in the same package folder? It's because the default path that your streams are looking for your files is the current working directory. Here is an example :
myproject
|___src
| |___main
| |___java
| |___io
| |___implementIo
|___writeModification.txt
|___modification.txt
This is the correct structure if you want to use the streams like you did (with just a simple file name in stream constructor argument). But if your files are not there, you have to specify the absolute path. Here is an example :
myproject
|___src
|___main
|___java
|___io
|___implementIo
|___writeModification.txt
|___modification.txt
And the correct way to access the files is this:
FileInputStream input = new FileInputStream("C://myproject//src//main//java//io//modification.txt");
Same for the output stream. (Please modify the path with your correct file location)

Directory not showing up in desktop, and file not being created?

The following program has the purpose of creating a directory,
folderforallofmyjavafiles.mkdir();
and making a file to go inside that directory,
File myfile = new File("C:\\Users\\username\\Desktop\\folderforallofmyjavafiles\\test.txt");
There are two problems though. One is that it says the directory is being created at the desktop, but when checking for the directory, it is not there. Also, when creating the file, I get the exception
ERROR: java.io.FileNotFoundException: folderforallofmyjavafiles\test.txt (The system cannot find the path specified)
Please help me resolve these issues, here is the full code:
package mypackage;
import java.io.*;
public class Createwriteaddopenread {
public static void main(String[] args) {
File folderforallofmyjavafiles = new File("C:\\Users\\username\\Desktop");
try {
folderforallofmyjavafiles.mkdir(); //Creates a directory (mkdirs makes a directory)
if (folderforallofmyjavafiles.isDirectory() == true) {
System.out.println("Folder created at " + "'" + folderforallofmyjavafiles.getPath() + "'");
}
} catch (Exception e) {
System.out.println("Not working...?");
}
File myfile = new File("C:\\Users\\username\\Desktop\\folderforallofmyjavafiles\\test.txt");
//I even tried this:
//File myfile = new File("folderforallofmyjavafiles/test.txt");
//write your name and age through the file
try {
PrintWriter output = new PrintWriter(myfile); //Going to write to myfile
//This may throw an exception, so I always need a try catch when writing to a file
output.println("myname");
output.println("myage");
output.close();
System.out.println("File created");
} catch (IOException e) {
System.out.printf("ERROR: %s\n", e); //e is the IOException
}
}
}
Thank you so much for helping me out, I really appreciate it.
:)

You're creating the Desktop folder in the C:\Users\username folder. If you check the return value of mkdir, you'd notice it's false because the folder already exists.
How would the system know that you want a folder named folderforallofmyjavafiles unless you tell it so?
So, you didn't create the folder, and then you try to create a file in the (nonexistent) folder, and Java tells you the folder doesn't exist.
Agreed that it's a bit obscure, using a FileNotFoundException, but the text does say "The system cannot find the path specified".
Update
You're probably confused about the variable name, so let me say this. The following are all the same:
File folderforallofmyjavafiles = new File("C:\\Users\\username\\Desktop");
folderforallofmyjavafiles.mkdir();
File x = new File("C:\\Users\\username\\Desktop");
x.mkdir();
File folderToCreate = new File("C:\\Users\\username\\Desktop");
folderToCreate.mkdir();
File gobbledygook = new File("C:\\Users\\username\\Desktop");
gobbledygook.mkdir();
new File("C:\\Users\\username\\Desktop").mkdir();

Java I/O Opening Files in External Program

I have a Java program that I am using to scan a directory to look for certain files. It finds the files but now I am trying to get the code to open the files once it finds them, but I am not sure how to do that.
Here a part of my code
File file = new File("/Users/******/Desktop/******");
String[] A = file.list();
File[] C = file.listFiles();
for (String string : A) {
if (string.endsWith(".txt")) {
System.out.println(string);
}
if (string.contains("******")) {
System.out.println("It contains X file");
}
}
I am trying to get it so once it finds the files ending in .txt, it opens all of them
I have tried using Google on how to solve his, I came across .getRuntime() and so I tried
try{
Runtime.getRuntime().exec("******.txt");
} catch(IOException e){
}
But I am not fully understanding how how this works. I am trying to get to so that once it finds the files it opens them. I am not trying to have the IDE open the text on the screen. I want the actual Notepad/TextEdit program to open.

File[] files = new File("/Users/******/Desktop/******").listFiles();
for (File f : files) {
String fileName = f.getName();
if (fileName.endsWith(".txt")) {
System.out.println(fileName);
}
if (fileName.contains("******")) {
System.out.println("It contains X file");
}
}

FileNotFoundException - Reading a text file in java

I'm getting a file not found exception from this code even though it's within the try catch statement and I'm not sure what's wrong, the file is within the project folder and is called 'someFile.txt'. This is the main method:
public static void main(String[] args) {
if (args.length == 0) {
System.out.println("no arguments given");
return;
}
double FRE = sortFile(args[0]);
System.out.println("Readability of file " + args[0] + "= " + FRE);
}
And this is the sortFile method where the exception occurs:
public static double sortFile(String FileName) {
int nWords = 0;
int nSyllables = 0;
int nSentences = 0;
File text = new File(FileName);
try {
Scanner sc = new Scanner(text);
while (sc.hasNext()) {
contents.add(sc.next());
++nWords;
}
sc.close();
for (String e : contents) {
getNumSyllables(e);
}
} catch (FileNotFoundException e) {
System.out.println("The file" + FileName + "could not be opened.");
e.printStackTrace();
}
double FRE = getFRE(nWords, nSyllables, nSentences);
return FRE;
}
Thanks for any help :)

well, the file does not exist in that location. Try to add
System.out.println(text.getAbsolutePath())
to see where the file is expected. Note, when you provide a relative path (e.g. some/path/filename.ext), this is relative to the working directory. The working directory is the folder your java program is started in.
If you're using an IDE (e.g. Eclipse, IntelliJ, Netbeans) you can define the working directory in your run configuration.
See:
Javadoc of java.io.File to learn how relative paths work inside a Java environment: http://docs.oracle.com/javase/7/docs/api/java/io/File.html
working dir: Getting the Current Working Directory in Java

I'm getting a file not found exception from this code even though it's
within the try catch statement
The try-catch does not prevent the Exception from being thrown. It merely executes the code in the catch block when an Exception is thrown, and you are just printing the stack trace in the catch block, which is what usually printed anyways on uncaught exceptions.
To resolve your actual issue, first try passing the full path to the file, verify that it works and then use Tim's answer to debug your absolute path.

Try launching your program with the absolute path.
java yourclassname absolutepath_to_someFile.txt

use java to create file in JavaScript

First of all I am iMacros scripts writer.
This is java function for writing a file (not fully complete but you will get the idea)
bufferedWriter = new BufferedWriter(new FileWriter(filename));
//Start writing to the output stream
bufferedWriter.write("Writing line one to file");
Now bellow is java function used in JavaScript to do the same task as the function above and I run that .js file in iMacros. Works like a charm.
//Function to write the file
function writeFile(filename, data)
{
try
{
//write the data
out = new java.io.BufferedWriter(new java.io.FileWriter(filename, true));
out.newLine();
out.write(data);
out.close();
out=null;
}
catch(e) //catch and report any errors
{
alert(""+e);
}
}
Now I need a java function that will create file and folder on Hard Drive location and I found this.
package com.mkyong.file;
import java.io.File;
import java.io.IOException;
public class CreateFileExample
{
public static void main( String[] args )
{
try {
File file = new File("c:\\newfile.txt");
if (file.createNewFile()){
System.out.println("File is created!");
}else{
System.out.println("File already exists.");
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
But now I need java function that will create folder and an empty file (with different extensions like .txt .csv etc.) and the function will work in JavaScript.
Can anyone give me some guide lines from the two examples above? How can I write a functions in Java and run it in JavaScript?

I won't claim to fully understand the question, but this is how to make sure some directory exists, and to create a random file in it:
// make the dir and ensure the entire path exists
File destinationDir = new File("c:\\whereever\you\want\that\file\to\land").mkdirs();
// make some file in that directory
File file = new File(destinationDir,"whateverfilename.whateverextension");
// continue with your code
if (file.createNewFile()){
System.out.println("File is created!");
}else{
System.out.println("File already exists.");
}

This function is used in iMacros .js file. It is a Java method called in JavaScript.
createFile("C:\\testingfolder","test.csv");
function createFile(folder,file)
{
destinationDir = new java.io.File(folder).mkdirs();
file = new java.io.File(folder,file);
file.createNewFile();
}
The function creates folder and in it creates a file.