A destructor and a delete operator

Question

Hello,
How to use the delete operator in JAVA?
Also what is the syntax of writting destructor?
class sample
LinkedList Lists;
sample()
Lists = new LinkedList();
~sample()
delete Lists;
The above code doesn't work in JAVA.
May I know the reason?

Answer 1

You may want to null a reference in this case:
class X {
    private BufferedImage image;
    public void setImage(URL url) throws IOException {
        image = null;
        image = ImageIO.read(url);
}Without nulling the image reference, the JVM may find it's out of memory and gc while reading the new image.
It may even find it has to expand memory to hold the new image.
It may only realize the old image is eligable for collection after doing this and updating the image
reference. (A smart JVM may realize that the last reference to the old image is about to disappear
and hurry it along, but you can imagine situations where the detachment is more subtle.)
Again there are a few instances where nulling a reference makes sense.