>From: ###@###.### (Jonathan Hardwick)
This does not look like form output to me.


Following the format and instructions of
http://www.javasoft.com/java.sun.com/GettingInTouch/BugReport.html

1. This is a bug.

2. It applies to the JDK 1.0.

3. JDK.

4. Popping a boolean array off a Stack causes a ClassCastException *if*
   the array was statically initialized, and the variable it is popped
   into is *not* declared on the same line as the pop.

5. SPARCstation 5, running Solaris 2.4.
   I've also had confirmation from a friend with WinNT 3.51 that he can
   duplicate the problem, although I haven't seen this first hand.

6. n/a

7. To reproduce the problem: save the code attached below as
   StackBooleanBug.java, compile it with javac, and run it with java.
   There will be a ClassCastException at line 42.

8. Exact text:
   java.lang.ClassCastException: java.lang.Object
        at StackBooleanBug.main(StackBooleanBug.java:42)

9. n/a


Notes: this is a weird one. It took me an hour to track down the exact
circumstances it occurs in. I can use a work-around in my current code,
but I'd really like the ability to use { } to initialize boolean arrays!

Jonathan Hardwick, ###@###.###
http://www.cs.cmu.edu/~jch


----- cut here ---------- StackBooleanBug.java ---------- cut here -----
/* Bug: if you initialize an array of booleans using { }, push it onto
   a Stack, and pop it off, sometimes you get a ClassCastException. If
   you initialize it one element at a time, or declare the variable it
   is popped into on the same line as the pop, it works.

   ~ > javac StackBooleanBug.java
   ~ > java StackBooleanBug
   java.lang.ClassCastException: java.lang.Object
        at StackBooleanBug.main(StackBooleanBug.java:42)

   Jonathan Hardwick, ###@###.###, 2/12/96, using Solaris JDK 1.0
 */

import java.util.Stack;

class StackBooleanBug {
  public static void main (String args[]) {
    Stack stack = new Stack ();

    // Initializing one element at a time works
    {
      boolean a[] = new boolean[2];
      boolean b[];
      a[0] = true; a[1] = false;
      stack.push (a);
      b = (boolean[]) stack.pop ();
    }

    // Declaring the variable on the same line as the pop works
    {
      boolean a[] = {true, false};
      stack.push (a);
      boolean b[] = (boolean[]) stack.pop ();
    }

    // Initializing all at once, and declaring variable in advance, fails.
    // BUG!
    {
      boolean a[] = {true, false};
      boolean b[];
      stack.push (a);
      b = (boolean[]) stack.pop ();
    }
  }
}

The description field as copied from bug report 1238230 follows:

from fp.bugs 3334:
>From: "Clark Elms" <###@###.###>
This does not look like form output to me.



 
The following code worked fine in the alpha3 release. Using the latest beta2
1.0 JDK, it does not work. It compiles fine, but I get a runtime error:
 
CODE:
 
public class xyz {
  protected static boolean xxx[][] = {{true, false}, {true, true}};
 
  public static void main(String args[]) {
    System.out.println("Hello World!");
  }
}
 
Compiled and run under alpha3:
 
% /home/GNU/lib/hotjava/bin/java xyz
Hello World!
 
Compiled and run under beta2:
 
% java xyz
java.lang.ArrayStoreException
        at xyz.<clinit>(xyz.java:4)
Hello World!
 
+----------------------+-----------------------------+
| Clark Elms | E-mail: ###@###.### |
| Sun Products | V-mail: (415) 506-2586 |
| Oracle Corporation | Fax: (415) 506-7361 |
+----------------------+-----------------------------+