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Date: Tue, 19 Feb 2013 08:56:11 +0000
From: lipska the kat <"nospam at neversurrender dot co dot uk">
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Subject: Re: abbreviated generic syntax
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On 18/02/13 23:35, Roedy Green wrote:
> On Mon, 18 Feb 2013 12:29:53 -0800 (PST), Lew<lewbloch@gmail.com>
> wrote, quoted or indirectly quoted someone who said :
>
>> The diamond operator distinguishes the generics usage.
>
> OK, that is obvious, but would it break any code?

Just to recap

1. ArrayList<String> a = new ArrayList<String>( 100 );

is quite clear

ArrayList<String> a = new ArrayList( 100 );

means you can do this and it compiles (1.6 and 1.7)

2. ArrayList<String> c = new ArrayList( 100 );
    c.add(new String("foo"));

but you will get a runtime exception if you try to do
Integer ops on the String

3. ArrayList<String> a = new ArrayList<>( 100 );

uses the 1.7 <> operator to allow the compiler to infer the type at
compile time from the type of the LHS, it's shorthand to allow you to
avoid having to type the generic params twice.

Given that generics is all about compile time type checking then I can't 
see anything breaking.

http://docs.oracle.com/javase/1.5.0/docs/guide/language/index.html

lipska

-- 
Lipska the KatŠ: Troll hunter, sandbox destroyer
and farscape dreamer of Aeryn Sun