Reputation: 629
If I pull out an object out of my HashMap, and then modify it. Will it modify inside the HashMap also? Or, do I need to set it back again to the HashMap after modifying it?
For example:
HashMap<Integer,TwoPoints> loc = new HashMap<Integer,TwoPoints>();
...
...
TwoPoints tp = loc.get(Id); //pulls out the object
tp.setPoint(group, new Point(x,y); //a method to set something inside the object I pulled.
Upvotes: 2
Views: 341
Reputation: 6043
You are getting a reference to the actual object, so any change would be reflected in it. You are not creating a copy.
Update:
Since I used the term "reference", I thought it is important to point out the definition. Under Java's hood, things are not quite as simple as this. But a reference (what you are doing) is getting the value of the pointer to the object.
Upvotes: 5