Name: wm7046 Date: 06/04/97


Sample Application

The compiler generates incorrect information for the local variables in this example.


1 public class GetArrayCrash
2 {
3
4 public static void main (String args[])
5 {
6
7 try
8 {
9 Class[] parmTypes = new Class[0];
10 Object[] parms = new Object[0];
11 }
12 catch (Exception e)
13 {
14 return;
15 }
16
17 String s = "Hello";
18 int y = 55;
19
20 System.exit(0);
21 }
22 }



The Problem

The variables parmTypes and parms are each given two entries in the local variable table, one of which is incorrect. Here is an excerpt of the javap -l output from the class file created by the compiler for the example above:


Line numbers for method void main(java.lang.String[])
   line 7: 0
   line 9: 0
   line 10: 5
   line 7: 10
   line 12: 13
   line 14: 14
   line 17: 15
   line 18: 18
   line 20: 21
   line 4: 25

Local variables for method void main(java.lang.String[])
   java.lang.String[] args pc=0, length=26, slot=0
   java.lang.Class[] parmTypes pc=5, length=8, slot=1
   java.lang.Object[] parms pc=10, length=3, slot=2
   java.lang.Class[] parmTypes pc=15, length=3, slot=1
   java.lang.Object[] parms pc=15, length=6, slot=2
   java.lang.String s pc=18, length=8, slot=1
   int y pc=21, length=5, slot=2



It is the second entry in the local variable table for both parms and parmTypes that is in error. According to the output above, parmTypes is in scope at line 17 and parms is in scope at lines 17-18. It is clear from the Java code above, that these entries should not be present.
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