JDK-4533479 : (reflect) invoke() may fail even for public method on IllegalAccessException
  • Type: Bug
  • Component: core-libs
  • Sub-Component: java.lang:reflect
  • Affected Version: 1.3.1
  • Priority: P4
  • Status: Closed
  • Resolution: Duplicate
  • OS: linux
  • CPU: x86
  • Submitted: 2001-11-30
  • Updated: 2012-09-28
  • Resolved: 2002-04-25
Related Reports
Duplicate :  
JDK-4071957 - (reflect) Method.invoke access control does not understand inner class scoping
Description
http://openide.netbeans.org/issues/show_bug.cgi?id=11679

A public method is defined in package private class. The package private class is then extended by a public class ni the same package. So:

  Method theMethod = publicIntance.getClass().getMethod("theMethod");

returns proper method (quering it for accessibility returns true). And it is possible to call the method without reflection:

  publicInstance.theMethod();

but reflection invocation

  theMethod.invoke(publicInstance, new Object[0])

throws the exception.
Comments
WORK AROUND setAccesible(true) to workaround it
11-06-2004
EVALUATION Using the provided description, I constructed the following test: FILE: Test.java package p; import java.lang.reflect.Method; class A { public void m() { System.out.println("a"); } } public class Test extends A { public static void main(String [] args) throws Exception { Test t = new Test(); Method m = t.getClass().getMethod("m", null); System.out.println(m + ": " + m.isAccessible()); t.m(); m.invoke(t, new Object[0]); } } Unfortunately I've been unable to reproduce the reported problem on linux, windows, or solaris using jdk1.2.2 - jdk1.4.1-b10. Running the above code always produces the following output: $ java p.Test public void p.A.m(): false a a Please provide a complete test case which reproduces the problem under at least jdk1.4. I read the comments at the netbeans.org issue page. It references a possible problem with the native code for Method.invoke. As of jdk1.4, this method is no longer implemented using native code. -- iag@sfbay 2002-04-24 Sorry I think your test is false (it does not perform cross package call). Well I am attaching test archive that contains bytecode that reproduces it on 1.4 and 1.3 as well. I also boubt that there is no native code anymore see stacktrace: public void bt4533.j479.A.m(): false java.lang.Exception: m called at bt4533.j479.A.m(Invoke.java:18) at bt4533.j479.Invoke.main(Invoke.java:28) java.lang.Exception: m called at bt4533.j479.A.m(Invoke.java:18) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:324) at bt4533.j479.Invoke.main(Invoke.java:30) -- ###@###.### 2002-04-25 The above stack trace does not match the provided example. The only main entry point in the example is in academy.reflect.TestAccessible. Using the provided class files (which appear to have been generated using jdk1.3 or the jdk1.4 compiler using the non-default behaviour), the output for this example using the last few jdk's is as follows: $ 13 $ java -version java version "1.3.0" Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.0) Java HotSpot(TM) Client VM (build 1.3.0, mixed mode) (iag@ribbit) ~///lang/reflect/4533479 $ java academy.reflect.TestAccessible >OK Exception in thread "main" java.lang.IllegalAccessException at java.lang.reflect.Method.invoke(Native Method) at academy.reflect.TestAccessible.main(TestAccessible.java:36) $ 131 $ java -version java version "1.3.1" Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.1-b24) Java HotSpot(TM) Client VM (build 1.3.1-b24, mixed mode) (iag@ribbit) ~///lang/reflect/4533479 $ java academy.reflect.TestAccessible >OK Exception in thread "main" java.lang.IllegalAccessException at java.lang.reflect.Method.invoke(Native Method) at academy.reflect.TestAccessible.main(TestAccessible.java:36) $ 14 $ java -version java version "1.4.0" Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-b92) Java HotSpot(TM) Client VM (build 1.4.0-b92, mixed mode) (iag@ribbit) ~///lang/reflect/4533479 $ java academy.reflect.TestAccessible >OK Exception in thread "main" java.lang.IllegalAccessException: Class academy.reflect.TestAccessible can not access a member of class academy.reflect.x.PackagePrivate with modifiers "public" at sun.reflect.Reflection.ensureMemberAccess(Reflection.java:57) at java.lang.reflect.Method.invoke(Method.java:317) at academy.reflect.TestAccessible.main(TestAccessible.java:36) $ 141 $ java -version java version "1.4.1-beta" Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1-beta-b10) Java HotSpot(TM) Client VM (build 1.4.1-beta-b10, mixed mode) $ java academy.reflect.TestAccessible >OK Exception in thread "main" java.lang.IllegalAccessException: Class academy.reflect.TestAccessible can not access a member of class academy.reflect.x.PackagePrivate with modifiers "public" at sun.reflect.Reflection.ensureMemberAccess(Reflection.java:57) at java.lang.reflect.Method.invoke(Method.java:317) at academy.reflect.TestAccessible.main(TestAccessible.java:36) There is no difference in behaviour when the files are compiled using jdk1.4.x. As you can see from the stack traces and as stated in my previous evaluation, there is no more native code in Method.invoke as of jdk1.4. Based on the provided example and the above behaviour, I conclude that this is a duplicate of 4071957. -- iag@sfbay 2002-04-25
25-04-2002