Java AccessControlException: accesso negato durante la scrittura

Durante la lettura di un .file csv non ho problemi. Ma alla fine del codice quando sto cercando di scrivere un nuovo valore, ricevo un'eccezione di accesso negato e non sono del tutto sicuro del perché. Qualcuno può spiegare cosa potrebbe causare questo?

private Path highScoreFile = Paths.get("/Applications/JavaFinalAssignment/highscore.csv");
public String checkhighScore()
{

try{
    InputStream input = new BufferedInputStream(Files.newInputStream(highScoreFile));
    BufferedReader reader = new BufferedReader(new InputStreamReader(input));
    String s = "";
    String delimiter = ",";
    s = reader.readLine();

    while(s!= null)
    {
        scoreArray = s.split(delimiter);    
        highScoreName = scoreArray[0];
        highScoreNum = Integer.parseInt(scoreArray[1]);         
        s = reader.readLine();
    }
    reader.close();

    }
    catch(Exception e)
    {
        JOptionPane.showMessageDialog(null, "ERROR: " + e);
    }
    String scoreReturn = (scoreArray[0] + " " + scoreArray[1]);
    return scoreReturn;
}

public void setHighScore(String name, int num)
{
    try
    {
    String s = "";
    String delimiter = ",";
    OutputStream output = new BufferedOutputStream(Files.newOutputStream(highScoreFile));
    BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(output));
    String numString = Integer.toString(num);
    s = name + delimiter + numString;
    writer.write(s);
    writer.close();
    }
    catch(Exception e)
    {
        JOptionPane.showMessageDialog(null, "Error saving high score file: " + e);
    }

}

MODIFICA:

Traccia dello stack aggiunta:

java.security.AccessControlException: access denied ("java.io.FilePermission" "/Users/Matt/Desktop/JavaFinalAssignment/highscore.csv" "write")
at java.security.AccessControlContext.checkPermission(AccessControlContext.java:366)
at java.security.AccessController.checkPermission(AccessController.java:560)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
at java.lang.SecurityManager.checkWrite(SecurityManager.java:979)
at sun.nio.fs.UnixChannelFactory.open(UnixChannelFactory.java:240)
at sun.nio.fs.UnixChannelFactory.newFileChannel(UnixChannelFactory.java:138)
at sun.nio.fs.UnixChannelFactory.newFileChannel(UnixChannelFactory.java:150)
at sun.nio.fs.UnixFileSystemProvider.newByteChannel(UnixFileSystemProvider.java:211)
at java.nio.file.spi.FileSystemProvider.newOutputStream(FileSystemProvider.java:430)
at java.nio.file.Files.newOutputStream(Files.java:170)
at FinalAssignment.setHighScore(FinalAssignment.java:335)
at FinalAssignment.GameOver(FinalAssignment.java:239)
at FinalAssignment.actionPerformed(FinalAssignment.java:140)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
at java.awt.Component.processMouseEvent(Component.java:6505)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
at java.awt.Component.processEvent(Component.java:6270)
at java.awt.Container.processEvent(Container.java:2229)
at java.awt.Component.dispatchEventImpl(Component.java:4861)
at java.awt.Container.dispatchEventImpl(Container.java:2287)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
at java.awt.Container.dispatchEventImpl(Container.java:2273)
at java.awt.Component.dispatchEvent(Component.java:4687)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:723)
at java.awt.EventQueue.access$200(EventQueue.java:103)
at java.awt.EventQueue$3.run(EventQueue.java:682)
at java.awt.EventQueue$3.run(EventQueue.java:680)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.awt.EventQueue$4.run(EventQueue.java:696)
at java.awt.EventQueue$4.run(EventQueue.java:694)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:693)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:244)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:163)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:147)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:139)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:97)