Implicit catches of any exception are generated by the compiler when a finally clause or synchronized block is present in the code. These clauses are not assigned to the most appropriate line number in the generated line number table. For example,

public class Bug3 {
    public static void main(String args[]) {
        try {
            throw new Exception();
        } catch (Exception e) {
            System.out.println("Caught!");
        } finally {
            System.out.println("Finally!");
        }

        synchronized(Bug3.class) {
            System.out.println("Synchronized!");
        }

        System.out.println("Done!");
    }
}

There are two implicit catch clauses generated by the compiler here (see javap output below). From bytecode 23 through 28 is given line 6, but ought to be assigned to 7 or possibly 8. Bytecodes 77 through 83 are assigned to line 12, but ought to be assigned to 13.

Method void main(java.lang.String[])
   0 new #7 <Class java.lang.Exception>
   3 dup
   4 invokespecial #8 <Method java.lang.Exception()>
   7 athrow
   8 astore_1
   9 getstatic #9 <Field java.io.PrintStream out>
  12 ldc #10 <String "Caught!">
  14 invokevirtual #11 <Method void println(java.lang.String)>
  17 jsr 29
  20 goto 40
  23 astore_2
  24 jsr 29
  27 aload_2
  28 athrow
  29 astore_3
  30 getstatic #9 <Field java.io.PrintStream out>
  33 ldc #12 <String "Finally!">
  35 invokevirtual #11 <Method void println(java.lang.String)>
  38 ret 3
  40 getstatic #13 <Field java.lang.Class class$Bug3>
  43 ifnonnull 58
  46 ldc #14 <String "Bug3">
  48 invokestatic #15 <Method java.lang.Class class$(java.lang.String)>
  51 dup
  52 putstatic #13 <Field java.lang.Class class$Bug3>
  55 goto 61
  58 getstatic #13 <Field java.lang.Class class$Bug3>
  61 astore_1
  62 aload_1
  63 monitorenter
  64 getstatic #9 <Field java.io.PrintStream out>
  67 ldc #16 <String "Synchronized!">
  69 invokevirtual #11 <Method void println(java.lang.String)>
  72 aload_1
  73 monitorexit
  74 goto 84
  77 astore 4
  79 aload_1
  80 monitorexit
  81 aload 4
  83 athrow
  84 getstatic #9 <Field java.io.PrintStream out>
  87 ldc #17 <String "Done!">
  89 invokevirtual #11 <Method void println(java.lang.String)>
  92 return
Exception table:
   from to target type
     0 8 8 <Class java.lang.Exception>
     0 23 23 any
    64 77 77 any

Line numbers for method void main(java.lang.String[])
   line 4: 0
   line 6: 9
   line 8: 30
   line 11: 40
   line 12: 64
   line 15: 84

Name: ssC76496 Date: 08/31/99

Implicit catch clauses are given correct line number
verified in the (1.3-0-D) build.
###@###.###, 1 Sept 99.
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