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[Dmitry <611284@xxxxxxxxxxxxxxxxxx>]

// The following code does not compile under openjdk-6, while it
compiles under openjdk-7 and sun-jdk-6

// Error message:
//Test.java:[10,14] invalid inferred types for K,V; inferred type does not conform to declared bound(s)
// inferred: C
// bound(s): java.lang.String

// java -version
// java version "1.6.0_23"
// OpenJDK Runtime Environment (IcedTea6 1.11pre) (6b23~pre11-0ubuntu1.11.10)
// OpenJDK 64-Bit Server VM (build 20.0-b11, mixed mode)

// uname -srvmpio
// Linux 3.0.0-15-generic #24-Ubuntu SMP Mon Dec 12 15:23:55 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux

import javax.annotation.Nullable;
import java.util.Comparator;
import java.util.TreeMap;

public class Test {
  public static void main(String[] args) {
    newTreeMap(String.CASE_INSENSITIVE_ORDER);
  }

  public static <C, K extends C, V> TreeMap<K, V> newTreeMap(
      @Nullable Comparator<C> comparator) {
    // Ideally, the extra type parameter "C" shouldn't be necessary. It is a
    // work-around of a compiler type inference quirk that prevents the
    // following code from being compiled:
    // Comparator<Class<?>> comparator = null;
    // Map<Class<? extends Throwable>, String> map = newTreeMap(comparator);
    return new TreeMap<K, V>(comparator);
  }
}

-- 
You received this bug notification because you are a member of OpenJDK,
which is subscribed to openjdk-6 in Ubuntu.
https://bugs.launchpad.net/bugs/611284

Title:
  OpenJDK compiler 6b20pre on Maverick doesn't recognize Generics
  Correctly

Status in “openjdk-6” package in Ubuntu:
  Confirmed

Bug description:
  OpenJDK compiler can't unify custom type defined in signature by
  generics.

  Example:

  import java.util.List;
  public class GenericBug {
      public <X extends String, Y extends List<X>, Z extends List<X>> Z add(X element, Y list){
          list.add(element);
          return list;
      }
  }

  This code compile correctly on Sun JDK but OpenJDK compiler displays error:
  "incompatible types
  required: Z
  found:    Y"
  But btw Z and Y is the same type: List<X>

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