Re: Newbie question - Disadvantages of java

From: Joona I Palaste (palaste_at_cc.helsinki.fi)
Date: 10/22/03 

Date: 22 Oct 2003 15:18:20 GMT

Gary Labowitz <glabowitz@comcast.net> scribbled the following:
> "Martin Wildam" <mwildam@may.co.at> wrote in message
> news:bn59uf$t1rgk$1@ID-114185.news.uni-berlin.de...
>> Hi folks,
>>
>> as I am about to switch to java, can somebody tell me the biggest
>> disadvantages of java so that I know where I will get the problems and
> where
>> the bottlenecks are?

> I can only point out the things that are the most difficult for most of my
> students:

> 1. Understanding the concept of passing by value. (And stop saying "I pass
> an object" until you really know what is happening.)
> 2. Understanding that only variables are passed from method to method.

Not "variables" - "values". For example:

public class Foo {
}
public class Bar {
  public Foo getFoo() {
    return new Foo();
  }
}
public class Baz {
  public void useFoo(Foo foo) {
  }
}

Now the code:
new Baz().useFoo(new Bar().getFoo());
passes a value of type "reference to a Foo" to the useFoo() method in
Baz. But this value is not stored in any variable.

> The simple points:

> 1. There are only nine kinds of variables. They all have exactly defined
> properties.

I.e. primitive types, references and array references? 

-- 
/-- Joona Palaste (palaste@cc.helsinki.fi) ------------- Finland --------\
\-- http://www.helsinki.fi/~palaste --------------------- rules! --------/
"The trouble with the French is they don't have a word for entrepreneur."
   - George Bush

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