How to make class only initial once and be called to share a variable?
I have a class,like follows:
public class demo{
private int a1;
private boolean available=false;
public synchronized void set(int value){
a1=value
}
public synchronized int get(){
return a1;
}
}
I make another two class to call demo class,in aa class,I set a1=5 under demo,
public class aa{
public void setvalue{
demo d=new demo();
d.set(5);
}
}
And get value from like follows:
public class bb{
public void getvalue(){
demo d=new demo();
System.out.println(d.get());
}
}
My question,how to make demo class can be initial once and make invoked by many class,but share a variable?
Thanks