Waiting for locked file to be released

[REMIYA]

I have a SQLite database file which is locked by the database connection. When I close the connection, although it is closed, it takes some time until the database file is actually unlocked. During this time I can not delete the database file. What is the best way to find when the file is unlocked?

this.conn.close();
System.out.println("Connection closed: "+this.conn.isClosed());
 
while(databaseFile.exists()){
        boolean result = databaseFile.delete();
        System.out.println("DB Deleted: "+result);
        if(result==true){return result;}
}

Any ideas?

[Rei12]

It is better to run while(databaseFile.exists()){...} in a new thread

[REMIYA]

It is better to run while(databaseFile.exists()){...} in a new thread

Thank you very much for your reply. Here is what I have now for the delete thread:

class Delete_Thread extends Thread {
    private File database_file;
 
    public boolean result = false;
 
    Delete_Thread(File database_file){
        this.database_file = database_file;
    }
    // This method is called when the thread runs
    public void run() {
        while(this.database_file.exists()){
            this.result = database_file.delete();
            System.out.println("DB Deleted: "+this.result);
        }
    }
}

Then I use the following code to invoke it:

Delete_Thread thread = new Delete_Thread(this.databaseFile);
 
thread.start();
 
while(thread.isAlive()){thread.join();}
 
if(thread.result==true)return true;

The code above works fine.

However, if I comment the line System.out.println("DB Deleted: "+this.result); the Thread continues forever.

May be I am doing something wrong?

Any help is appreciated.

[REMIYA]

SOLVED

The problem has been the unit test itself

During the unit test a second connection to the database was opening, that prevented the database deletion until being closed.

Thank you for your help.