final keyword in method parameters

java final
Aly picture Aly · Feb 10, 2010 · Viewed 151k times · Source

I often encounter methods which look like the following:

public void foo(final String a, final int[] b, final Object1 c){
}

What happens if this method is called without passing it final parameters. i.e. an Object1 that is later changed (so is not declared as final) can be passed to this method just fine

Answer

Thirler picture Thirler · Feb 10, 2010

Java always makes a copy of parameters before sending them to methods. This means the final doesn't mean any difference for the calling code. This only means that inside the method the variables can not be reassigned. (note that if you have a final object, you can still change the attributes of the object).

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