Re: pass by reference

"angelochen960@xxxxxxxxx" <angelochen960@xxxxxxxxx> wrote in news:0a4ad57b-
60d2-4b7a-93c5-e53b20628c81@xxxxxxxxxxxxxxxxxxxxxxxxxxxx:

Hi guys,

Thanks for all the answers, I'm kind of surprised that a simple
question got so many answers! is this statement correct:

Everything in Java are passed by value, in the case of an object, a
reference to the object is passed, which is a value too, updating the
fields in the reference does reflect the changes. anyway, maybe I
should not try to understand java in a C++ manner.

but i can't help, String is a object, so a reference should be the one
passed, and why we can not update the field in the String object? and
then where is the field of the String?



Yes, I was wrong in my

public void myFunc(String s) {
s = "123";
}

because that compiles exactly as

public void myFunc(String s) {
s = new String("123");
}


If the String class had a method setValue() we could write

public void myFunc(String s) {
s.setValue("123");
}

but it does not, and we can't.

Some kind of a wrapper class is needed with the methods required.

.

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