How to kill javaw.exe in java at runtime

Question

I have a java code that generates output file. When I want to delete this output file at runtime in this java code, it can not be deleted. For example:

File file2= new File("D:\\eclipse-jee-mars-R-win32-x86_64\\eclipse\\output.txt");
    if(file2.delete()){
                System.out.println(file2.getName() + " is deleted!");
            }
            else{
                System.out.println("Delete operation is failed.");
            }

This code doesn't work. ("output.txt" file is generated on this directory and can be seen in folder.)

In fact When I want to delete on the windows folder it can not delete and it gives this error. I will translate into English.

If I kill "javaw.exe" process in the task manager, I can delete this file on the folder. My question is that, How can I solve this problem? I want to kill "javaw.exe" at runtime in java so this file can be deleted. How to kill this "javaw.exe" process at runtime in java? If I kill "javaw.exe" process at runtime in the code, will I encounter another problem?

How I generate this output file?

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.Arrays;
import java.io.FileWriter;

public class code{

    public static void main(String[] args) {

        try (BufferedReader br = new BufferedReader(new FileReader(args[0])))
        {

            int lines = 0;
            while (br.readLine() != null) lines++; // to get text's number of lines 

            String sCurrentLine;
            BufferedReader br2 = new BufferedReader(new FileReader(args[0])); //to read and sort the text

            String[] array; //create a new array
            array = new String[lines];

            int i=0;
            while ((sCurrentLine = br2.readLine()) != null) {//fill array with text content
                array[i] = sCurrentLine;
                i++;
            }
            Arrays.sort(array); //sort array


            FileWriter fw = new FileWriter("output.txt");

            for (i = 0; i < array.length; i++) { //write content of the array to file
                fw.write(array[i] + "\n");
            }
            fw.close();


            System.out.println("Process is finished.");


        } catch (IOException e) {
            e.printStackTrace();
        } 

    }
}

In fact, I am developing web application that compile/execute java codes online by using JSP. I didn't share all parts because it is hard to understand if I share all parts of my code. This code generates an output file, it takes input file, sorts then crate a new "output.txt" file. I want to in my JSP delete this file but It couldn't be deleted because javaw.exe is still running.

The output file is generated on the "D:\eclipse-jee-mars-R-win32-x86_64\eclipse" directory anyway, I don't want to explain details to prevent mind confusion.

Maybe you have to use a System.exit(int i) at the end of your program?! — mrbela, Apr 25 '16 at 11:54
Good question, by using FileWriter fw = new FileWriter("output.txt"); for (i = 0; i < array.length; i++) { //write content of the array to file fw.write(array[i] + "\n"); } fw.close(); not bufferedwriter. — Gürkan Çatak, Apr 25 '16 at 11:56
If the file exists and no program has a handle on it (!), the file can be deleted without any problems. If you open a `FileInputStream` or a `FileReader` on that file, then the handle is released by calling the `close` method. Please give us an [MCVE](http://stackoverflow.com/help/mcve). Something else: Asking for "how to kill a process", when in reality you have problems with deleting a file is called an [XY problem](http://meta.stackexchange.com/questions/66377/what-is-the-xy-problem). — Seelenvirtuose, Apr 25 '16 at 11:59
"javaw.exe" is your program which running, and how you generate that file? — keronconk, Apr 25 '16 at 12:11
Have a look at this post. Ideally you should probably be wrapping the file in a stream. http://stackoverflow.com/questions/991489/i-cant-delete-a-file-in-java — klog, Apr 25 '16 at 12:17

score 0 · Answer 1 · answered Apr 25 '16 at 17:24

I solved my problem. I forgot to close my BufferedReader. There are some transition methods in my program I couldn't share all of them. These transition methods are about file handling and at one point, I forget to close BufferedReader that I created another location. After I closed my BufferedReader, I could dynamically delete "output.txt" at someplace else. I am sharing my viewtext method. It is used to view output file in jsp textarea.

public static String viewtext(String pathname) throws IOException{


         String a="";

         File f = new File(pathname);
         if(f.exists() && !f.isDirectory()) { 
             BufferedReader br = new BufferedReader(new FileReader(pathname));
              for (String line; (line = br.readLine()) != null;) {
                  a = a  +  line + "\n"  ;
                  }
              br.close(); //I added just this 
             return a;
         }
         else{
            // br.close(); //No need here, if there is no file no close is needed.
             return "Your file is not found!";
     }

}

Also there is no need to kill javaw.exe process.

How to kill javaw.exe in java at runtime

1 Answers1