RFR: JDK-8280004: DCmdArgument<jlong>::parse_value() should handle NULL input [v3]

[Thomas Stuefe]

> Hi,
> 
> may I have eyes please on this simple fix (Sonarcloud-inspired) which sanitizes the error output of DCmdArgument<jlong>::parse_value():
> - since the input can be NULL, we should handle NULL
> - we also limit parroting of invalid input to 64 chars max
> - we also do not need a temporary RA buffer to assemble the output
> 
> Example output with patch, first a short, then a long invalid numeric parameter:
> 
> 
> thomas at starfish:~$ jcmd Simple GC.class_histogram -parallel=hallo
> 399746:
> java.lang.IllegalArgumentException: Integer parsing error in command argument '-parallel'. Could not parse: "hallo".
> thomas at starfish:~$ jcmd Simple GC.class_histogram -parallel=hallo012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789
> 399746:
> java.lang.IllegalArgumentException: Integer parsing error in command argument '-parallel'. Could not parse: "hallo01234567890123456789012345678901234567890123456789012345678...".
> 
> 
> Thanks, Thomas

Thomas Stuefe has updated the pull request incrementally with one additional commit since the last revision:

  fix copyright

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/7079/files
  - new: https://git.openjdk.java.net/jdk/pull/7079/files/8af94135..a6ca495c

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=7079&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=7079&range=01-02

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7079.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7079/head:pull/7079

PR: https://git.openjdk.java.net/jdk/pull/7079