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Command Works Through Command Line, but Not When Using ProcessBuilder

I'm writing a program that includes a feature where the user can type in Java code into a text box and be able to compile and run it. The error I get is:
The two directories shown at the top are correct, and the command works when I do it manually through command prompt from the same working directory. I'm using Windows 10, and also here's the code:
public Process compile() throws IOException {
save(); //saves changes to source file
System.out.println(file.getCanonicalPath());
ProcessBuilder processBuilder = new ProcessBuilder("javac", file.getCanonicalPath());
processBuilder.directory(new File(settingsFile.getJdkPath()));
System.out.println(processBuilder.directory());
Process process = processBuilder.start(); //Throws exception
this.compiledFile = new File(file.getParentFile(), file.getName().replace(".java", ".class"));
return process;
}
File to compile:
Working directory:

Using this code, I was able to compile a Test.java file into a Test.class file on my Desktop.
import java.io.IOException;
public class App {
public static Process compile() throws IOException {
String myFilePath = "C:\\Users\\redacted\\Desktop\\Test.java";
String javacPath = "C:\\Program Files\\Java\\jdk1.8.0_171\\bin\\javac.exe";
ProcessBuilder processBuilder = new ProcessBuilder(javacPath, myFilePath);
return processBuilder.start();
}
public static void main(String[] args) throws IOException {
Process process = compile();
}
}
Using String javacPath = "javac.exe"; also worked, but that could be because my JDK bin is on my PATH variable.
There is something wrong with your paths or permissions in the ProcessBuilder constructor call.

Unix executable changes to TextEdit document when copied

I have the following script, of which you can see below. The function of this Java script is to copy a Mac app, of which is placed in the same folder as the java program. It first finds the path of the folder, which the app and java program is in. It then copies all the content to the documents folder on the Mac device. When that is done it is then supposed to run that app of which it has copied to the documents folder.
The only issue is that it isn't able to do so. The reason being that whenever it copies the app, the JavaAppLauncher which is found within the content of the mac app has changed from a unix executable to a regular TextEdit document and thus can't actually launch the app. However if I were to copy the app manually by copying it myself and not using the java program, there is no issue. I am not sure whether this issue is caused by my code, or whether it is just a general thing?
Important note, the .app does work when I just run the regular non copied version, but as soon as it is the copied version, which as been copied through Java it doesn't work because the change of the Unix executable.
public class LaunchProg {
static String usernameMac2 = System.getProperty("user.name");
static File propFile = new File (".");
static String pathString = propFile.getAbsolutePath();
static int pathhLeng = pathString.length();
static int pathReaLeng = pathhLeng -1;
static String filNamMac = "AppNam.app";
static String pFPathRelMac = pathString.substring(0,pathReaLeng);
private static final File fSourceMac = new File(pFPathRelMac);
private static final File AppFold = new File ("/Users/" + usernameMac2 + "/Documents");
static File fileCret = new File("fCret.txt");
public static void main(String[] args) throws IOException {
System.out.println(pFPathRelMac);
launchMac();
}
static void launchMac() throws IOException {
if (!fileCret.exists()){
try {
FileUtils.copyDirectory(fSourceMac, AppFold);
PrintWriter pFW = new PrintWriter(fileCret);
pFW.println("Created File For Check");
pFW.close();
} catch (IOException e) {
e.printStackTrace();
} finally {
String command = "open /Users/" + usernameMac2 + "/Documents/AppNam.app";
Process staAp2 = Runtime.getRuntime().exec(command);
}
}
}
}

Reading from one java file and writing to another one

I want content of one .java file to the another .java file. I am doing this with FileInput/FileOutput Stream classes in eclipse IDE. I have put one file named FileToFile.java inside Nisarg/src/FiliIO(package).
And I am getting FileNotFoundException at line 12. I want to know why this exception raised?
This is what I actually got at runtime..
Exception in thread "main" java.io.FileNotFoundException: FileToFile.java (The system cannot find the file specified)
at java.io.FileInputStream.open0(Native Method)
at java.io.FileInputStream.open(Unknown Source)
at java.io.FileInputStream.<init>(Unknown Source)
at java.io.FileInputStream.<init>(Unknown Source)
at FileIO.FileToFile.main(FileToFile.java:12)
This is a piece of code:
package FileIO;
import java.io.*;
public class FileToFile {
/**
* #param args
*/
public static void main(String[] args)throws IOException {
// TODO Auto-generated method stub
FileInputStream i=new FileInputStream("FileToFile.java");// Current file content is wanted to be written...
FileOutputStream o=new FileOutputStream("M.java"); // Destination file which is also in same place.(Nisarg/src/FileIO(package)...
int a=0;
while((a=i.read())!=-1)
{
o.write((byte)a);
}
o.close();
i.close();
System.out.print("Done");
}
}
What should be done to achieve my requirements? I have searched but I was unable to where to put the file. Thank you in advance..!!

Java cant find your input file FileToFile.java, that's what is basically mean. You either can specify a absolute file path or find out what folder your main class is located at and place your file FileToFile.java there.
Find the current directory of your main class, use System.getProperty("user.dir")

package fileIO;
import java.io.*;
public class FileToFile {
public static void main(String[] args)throws IOException {
FileInputStream i=new FileInputStream("src\\fileIO\\FileToFile.java");
FileOutputStream o=new FileOutputStream("F:\\M.java");
int a=0;
while((a=i.read())!=-1)
{
o.write((byte)a);
}
o.close();
i.close();
System.out.print("Done");
}
}

You should have to use
1)the absolute path for your file
2)Find the current directory using System.getProperty("user.dir") and place your file there.
3)You can change your current working directory for your application by Go to
run configuration >> Arguments >> Other radio button. Then enter an absolute path name as the working directory for the launched application.Place your file in the specified directory.

FileNotFoundException in Eclipse

In Eclipse, my directory structure is this:
-src
-com.xxx.yyy
- MyClass.java
-assets
- car.txt
MyClass.java looks like this :
public class MyClass {
private static String FILE_PATH = "../assets/car.txt";
public static void main(String[] args) {
try {
//FileNotFoundException
FileInputStream fis = new FileInputStream(new File(FILE_PATH));
}
...
}
}
I this by default, the classpath is src/, so I point to my car.txt file by ../assets/car.txt. But I get :
java.io.FileNotFoundException: ../assets/car.txt (No such file or directory)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(FileInputStream.java:138)
Why ?

Relative file paths a relative to the execution, assuming that the program is executed in the same location as the src and assets directory, then the path should be assets/car.txt
You can check the current execution location using System.out.println(new File(".").getCanonicalPath());

Whe you run the program it is compiled to the parent folder of the src folder as far as I know. You should better add the assets folder to your build path and access the file using getClass().getResource[AsStream]().
To add the folder do the following:
Right click on your project
Click Build Path
Choose Configure Build Path
Select Source
Click Add Folder...
Select your assets folder
Inside your code you can either call it with MyClass.class.getResource[AsStream]() or getClass().getResource[AsStream]().
getResource() returns an URL and getResourceAsStream() an InputStream. Both methods expect a path as parameter. Check the docs for more information.

Your path is incorrect
Since you are inside com.xxx.yyy, you are inside three folders. You need to get out of all of them.
So you can use, the relative path as
FILE_PATH = "../../../assets/car.txt";
As src is a source folder, all the contents come directly in the classpasth, you can also use
FILE_PATH = "assets/car.txt";

You are in second level in directory structure.
Try
FILE_PATH = "../../assets/car.txt";

Hope, this will help you...
package com.xxx.yyy;
import java.io.File;
import java.io.FileInputStream;
public class MyClass {
private static String FILE_PATH = "src/assets/car.txt";
public static void main(String[] args) {
try {
//FileNotFoundException
FileInputStream fis = new FileInputStream(new File(FILE_PATH));
}
catch (Exception e){
e.printStackTrace();
}
}
}

Ankit Lamba 's suggestion works: that's using String FILE_PATH = "assets/car.txt";

FileInputStream look into root of Jar

I have a FileInputStream in a class in the package com.nishu.ld28.utilities, and I want to access sound files in the folder Sounds, which is not in the com.nishu.ld28 package. I specify the path for loading like so:
"sounds/merry_xmas.wav"
And then try to load it like this:
new BufferedInputStream(new FileInputStream(path))
When I export the jar, the command line prompt that I run it through says it can't find the file. I know how to access the files when I am running the program in Eclipse, but I can't figure out how to point the FileInputStream to the Sounds folder when I export it.
Edit: As requested, here's my code:
public void loadSound(String path) {
WaveData data = null;
data = WaveData.create(GameSound.class.getClassLoader().getResourceAsStream(path));
int buffer = alGenBuffers();
alBufferData(buffer, data.format, data.data, data.samplerate);
data.dispose();
source = alGenSources();
alSourcei(source, AL_BUFFER, buffer);
}
WaveData accepts an InputStream or other types of IO.

You don't need a FileInputStream, because you aren't reading from the filesystem. Use the InputStream returned by ClassLoader.getResourceAsStream(String res) or Class.getResourceAsStream(String res). So either
in = ClassLoader.getResourceAsStream("sounds/merry_xmas.wav");
or
in = getClass().getResourceAsStream("/sounds/merry_xmas.wav");
Note the leading slash in the second example.

I would put the com.nishu.ld28.utilities in the same package of your class , let's call it MyClass.
Your package:
Your code:
package com.nishu.ld28.utilities;
import java.io.InputStream;
public class MyClass {
public static void main(String[] args) {
InputStream is = MyClass.class.getResourceAsStream("sound/merry_xmas.wav");
System.out.format("is is null ? => %s", is==null);
}
}
Output
is is null ? => false