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

[Thomas Stuefe]

Hi,

may I have eyes please on this simple fix 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

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Commit messages:
 - sanitize error message

Changes: https://git.openjdk.java.net/jdk/pull/7079/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7079&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8280004
  Stats: 10 lines in 1 file changed: 4 ins; 4 del; 2 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