Re: Explain this Technique -- new() followed by an anonymous class declaration
On 2005-09-16, SMAccount <SMAccount@xxxxxxxxx> wrote:
> I took the following example from the Sun Java Tutorial on writing
> Swing Programs (see link below). The code invokes "new Runnable()"
> followed by an anonymous class declaration. I am new to Java, and I
> have never seen anything like this in any other language. Anyone know
> where there is any documentation on this type of technique? When you
> can use it? What are its' limits?
[snip]
See the "Class Instance Creation Expressions" section of The Java
Language Specification, say at
http://java.sun.com/docs/books/jls/second_edition/html/expressions.doc.html#41147
for the documentation, which includes the information that when doing
a "new" on "the name of an interface then an anonymous direct subclass
of Object that implements the interface" is declared.
You can use it where every you can use a ClassInstanceCreationExpression.
Its limits are those of an anonymous class, such the class not being able
to have an explicitly declared constructor.
.
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