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  1. JDK
  2. JDK-4452115

javac allows access to a local class by using a synthetic name

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      Description



      Name: poR10007 Date: 04/28/2001



      Javac (jdk1.4.0beta-b62, jdk1.3.1-b23) allows access to a local
      class by using a synthetic name that compiler constructs to represent
      a local class. Through this synthetic name the class is accessible
      even outside of its scope.

      That contradicts the following assertions of JLS-2,
      14.3 "Local class declarations":

        "The scope of a local class declared in a block is the rest of the
         immediately enclosing block, including its own class declaration."
         
        "A local class does not have a canonical name, nor does it have a fully
         qualified name."
         
      The following test demonstrates the behavior:

      --stmt16503_a.java--------------------------------------------
      public class stmt16503_a {
          public static void test() {
              class Local {};
          }
      }
      --------------------------------------------------------------

      --stmt16503.java----------------------------------------------
      public class stmt16503 {
          public static void main(String argv[]) {
              Object a = new stmt16503_a$1$Local();
          }
      }
      --------------------------------------------------------------

      The class Local can be accessed from a method of class stmt16503 by using
      the name stmt16503_a$1$Local. To reproduce the bug classes should be compiled
      in sequence - stmt16503_a.java, then stmt16503.java.
      Compiler correctly detects the error when classes are compiled together.

      The execution log is following:

      $ jdk1.4.0beta-b62/solsparc/bin/java -version
      java version "1.4.0-beta"
      Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-beta-b62)
      Java HotSpot(TM) Client VM (build 1.4.0-beta-b62, mixed mode)
      $ jdk1.4.0beta-b62/solsparc/bin/javac -d . stmt16503_a.java stmt16503.java; echo
      $?
      stmt16503.java:3: cannot resolve symbol
      symbol : class stmt16503_a$1$Local
      location: class stmt16503
              Object a = new stmt16503_a$1$Local();
                             ^
      1 error
      1
      $ jdk1.4.0beta-b62/solsparc/bin/javac -d . stmt16503_a.java; echo $?
      0
      $ jdk1.4.0beta-b62/solsparc/bin/javac -d . stmt16503.java; echo $?
      0
      $ jdk1.4.0beta-b62/solsparc/bin/java stmt16503; echo $?
      0
      $

      ======================================================================

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              • Assignee:
                gafter Neal Gafter
                Reporter:
                passunw Pas Pas (Inactive)
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