[687] in java-interest
java-interest-digest V1 #83
daemon@ATHENA.MIT.EDU (java-interest@java.sun.com@cs.prus)
Thu Jul 13 09:07:04 1995
From: java-interest@java.sun.com@cs.prusec.com
To: crusher.cs.prusec.com!java.sun.com!java-interest@java
Date: Thu, 13 Jul 95 11:55:03 GMT
Not-Delivered-To: due to 11 Transfer Failure
ORIGINAL MESSAGE ATTACHED
(rmail: Error # 22 'Surrogate command failed', rc = 1)
En-Route-To: !walter-ws.cs.prusec.com.#walter.hjelmar!walterh
======= Surrogate command =======
:smtpqer cs.prusec.com!java.sun.com!java-interest walter-ws.cs.prusec.com.#walter.hjelmar walterh
==== Start of stdout ===
==== Start of stderr ===
:UX:smtpqer: INFO: unknown host <walter-ws.cs.prusec.com.#walter.hjelmar>
En-Route-To: !walter-ws.cs.prusec.com.#walter.hjelmar!walterh
From smtp Thu Jul 13 07:55 EDT 1995
Received: from cs.prusec.com by prusec.prusec.com; Thu, 13 Jul 95 07:55 EDT
Received: from prufsg.cs.prusec.com by crusher.cs.prusec.com (AIX 3.2/UCB 5.64/4.03)
id AA09999; Thu, 13 Jul 1995 07:56:09 -0400
Received: from java.sun.com by prusec.prusec.com; Thu, 13 Jul 95 07:54 EDT
Received: (from majordom@localhost) by java (8.6.12/8.6.12) id XAA14094 for java-interest-digest-outgoing; Wed, 12 Jul 1995 23:30:08 -0700
From: java-interest@java.sun.com@cs.prusec.com
Date: Wed, 12 Jul 1995 23:30:08 -0700
Message-Id: <199507130630.XAA14094@java>
>From: owner-java-interest-digest@java.sun.com
To: java-interest-digest@java.sun.com
Subject: java-interest-digest V1 #83
Reply-To: java-interest@java.sun.com@cs.prusec.com
Errors-To: owner-java-interest-digest@java.sun.com@cs.prusec.com
Content-Length: 2057
Content-Type: text
Precedence: bulk
X-Info: To unsubscribe, send 'unsubscribe' to java-interest-digest-request@java.sun.com
java-interest-digest Thursday, 13 July 1995 Volume 01 : Number 083
In this issue:
Re: Class.newInstance() question
Re: Class.newInstance() question
----------------------------------------------------------------------
From: cmcmanis@scndprsn.Eng.Sun.COM (Chuck McManis)
Date: Wed, 12 Jul 1995 22:43:14 -0700
Subject: Re: Class.newInstance() question
The best way to do this is to define an interface that objects you want
to create this way can use. Thus you would define:
public interface Loadable {
public Object make(String parameter);
}
And then in objects you were instantiating you would use:
Class foo = Class.forName("MyCustomClass");
return ((Loadable)(foo.newInstance()).make("Some parameter"));
Now you could also protect it like this:
Object x;
try {
x = (Loadable) (foo.newInstance()).make("Some Parameter");
} catch (Exception e) {
// didn't work , probably doesn't implement loadable
x = null;
}
return (x);
So if the object you were instantiating couldn't be made loadable it wouldn't.
You would write a loadable object like so:
class Bletch implements Loadable {
/** MUST have a null constructor if you want newInstance to work */
public Bletch(){
}
public Bletch(String xyzzy) {
}
public Bletch make(String fooey) {
return new Bletch(fooey);
}
}
A bit of overhead but it gets the job done.
- --Chuck
------------------------------
From: jpayne@starwave.com (Jonathan Payne)
Date: Wed, 12 Jul 1995 23:27:21 -0700
Subject: Re: Class.newInstance() question
You should just create your class in the normal way
YourClass foo = new ("YourClass");
and then call a well-defined method, perhaps initialize(...) to
actually initialize it as if you had passed the args in the
constructor.
Oh, the above example should contain a cast from the new expression to
(YourClass), since it's not known at compile time what type new will
return.
------------------------------
End of java-interest-digest V1 #83
**********************************
-
Note to Sun employees: this is an EXTERNAL mailing list!
Info: send 'help' to java-interest-request@java.sun.com
