Uploaded image for project: 'JDK'
  1. JDK
  2. JDK-6547358

j.l.i.: manifest attribute 'Can-Retransform-Classes' is ignored by isRetransformClassesSupported()

XMLWordPrintable

    • b26
    • generic
    • generic
    • Verified

      Filed By : JCK team
      JDK : java full version "1.6.0-fcs"
      JCK : 6a
      Platform[s] : FAIL - seems to be all
      switch/Mode : default
      JCK test owner : http://javaweb.sfbay/jcce/tcks/jck/docs/others/owners.jto
      Failed tests:
        api/java_lang/instrument/Instrumentation/index.html#Instrumentation[Instrumentation221]
        api/java_lang/instrument/Instrumentation/attach.html#InstrumentationAttach[Instrumentation221]

      Problem description
      ===================
      The javadoc specification for the Instrumentation.isRetransformClassesSupported() method at:
        http://java.sun.com/javase/6/docs/api/java/lang/instrument/Instrumentation.html#isRetransformClassesSupported()
      states as follows:
        ---Excerpt-from-spec---
        The ability to retransform an already loaded class is an optional capability of a JVM.
        Retransformation will only be supported if the Can-Retransform-Classes manifest attribute
        is set to true in the agent JAR file (as described in the package specification) and
        the JVM supports this capability.
        ---End-of-excerpt---

      However, when 'Can-Retransform-Classes' manifest attribute does not exist in manifest file
      or when it is set to 'false', the call of isRetransformClassesSupported() still returns 'true'.

      Please see attached minimized test (test.tar.gz) to reproduce the failure.

      Minimized test output:
      ======================
      >java -javaagent:agent1.jar -javaagent:agent2.jar Test
      FAILED: agent1 unexpectedly supports retransformation
      FAILED: agent2 unexpectedly supports retransformation
      main is invoked

      Additional info:
      ================
      > uname -a
      SunOS d-espb04-125-170 5.10 Generic_118833-33 sun4u sparc SUNW,Ultra-60

            dcubed Daniel Daugherty
            ygaevsky Yuri Gaevsky (Inactive)
            Votes:
            0 Vote for this issue
            Watchers:
            0 Start watching this issue

              Created:
              Updated:
              Resolved:
              Imported:
              Indexed: