Code review request for 8012044: Give more information about self-suppression from Throwable.addSuppressed

[Jason Mehrens]

The landmines are the retrofitted exception classes as shown here  https://netbeans.org/bugzilla/show_bug.cgi?id=150969 and https://issues.jboss.org/browse/JBREM-552.  Really, if the ISE or IAE is thrown it is going to suppress 'this' and 'cause'.  It would be nice to see the given 'cause' show up in a log file when tracking down this type of bug. Date: Fri, 12 Apr 2013 10:35:40 -0700
From: joe.darcy at oracle.com
To: jason_mehrens at hotmail.com
CC: core-libs-dev at openjdk.java.net
Subject: Re: Code review request for 8012044: Give more information about self-suppression from Throwable.addSuppressed


  
    
  
  
    Hi Jason,

      

      Hmm. This is the current initCause implementation from JDK 8:

      

          public synchronized Throwable initCause(Throwable cause) {

              if (this.cause != this)

                  throw new IllegalStateException("Can't overwrite
      cause");

              if (cause == this)

                  throw new IllegalArgumentException("Self-causation not
      permitted");

              this.cause = cause;

              return this;

          }

      

      It wouldn't be unreasonable to change the second throw to

      

              if (cause == this)

                  throw new IllegalArgumentException("Self-causation not
      permitted", cause);

      

      but I think there is less motivation to do so than in the
      addSuppressed case since addSuppressed gets called in
      compiler-generated code that isn't visible in the original
      sources.

      

      -Joe