Re: RFR(L): 8218628: Add detailed message to NullPointerException describing what is null.

[coleen . phillimore]

On 5/7/19 9:36 AM, Lindenmaier, Goetz wrote:
Hi,

Please have a look at this further improved webrev:
http://cr.openjdk.java.net/~goetz/wr19/8218628-exMsg-NPE/09/
http://cr.openjdk.java.net/~goetz/wr19/8218628-exMsg-NPE/09-incremental/

Harold, Coleen, thanks for pointing me to those methods.
I'm using them now. This simplifies the helper methods
considerably.

Ralf, thanks for looking at the messages!
I now suppress the "static " and
"The return value of '" strings in the array subscript
expressions and added corresponding test cases.

About "can not" versus "cannot", what I find in the
net "cannot" is to be preferred.  Any comments on that?
By native speakers?
See example messages here:
http://cr.openjdk.java.net/~goetz/wr19/8218628-exMsg-NPE/09/output_with_debug_info.txt

Cannot is apparently preferable in English.  Native speaker (only 
language) but somebody had to tell me.

Coleen

Further, I fixed a build issue with the solaris compiler.
All handling of bci is now unsigned.

Best regards,
   Goetz.




-----Original Message-----
From: Schmelter, Ralf
Sent: Dienstag, 7. Mai 2019 14:35
To: Lindenmaier, Goetz <goetz.lindenma...@sap.com>; Java Core Libs <core-
libs-...@openjdk.java.net>; hotspot-runtime-...@openjdk.java.net; Coleen
Phillimore (coleen.phillim...@oracle.com) <coleen.phillim...@oracle.com>
Subject: RE: RFR(L): 8218628: Add detailed message to NullPointerException
describing what is null.

Hi Goetz,

I've played with the messages a little bit and they generally look good. But 
I've
come across two which look strange:
  - 'o[static Test.INDEX]' is null. Can not invoke method 'int
java.lang.Object.hashCode()'
  - 'o[The return value of 'int java.lang.String.hashCode()]' is null. Can not 
invoke
method 'int java.lang.Object.hashCode()'.

Here is the test program to reproduce these:
public class Test {
     public static int INDEX = 2;

     public static void main(String[] args) {
         Object[] o = new Object[10];
         try {
              o[INDEX].hashCode();
         } catch (Exception e) {
             e.printStackTrace();
         }
         try {
              o["".hashCode()].hashCode();
         } catch (Exception e) {
             e.printStackTrace();
         }
     }
}

And 'Can not' should be 'Cannot'?

Best regards,
Ralf