Please provide default impl for new methods on Collection/Map interfaces

[Aleksey Shipilev]

Well, I'm puzzled at this point. If your classes are extending
AbstractCollection, they implicitly extend Collection, and Collection
has default methods to be picked up.

Are you compiling with lambda/lambda javac? Vanilla JDK8 javac would not
work, since it does not know anything about default methods yet.

-Aleksey.

On 09/20/2012 03:14 PM, Peter Reilly wrote:
> No problem.
> 
> My code extends AbstractCollection and AbstractMap.
> 
> The changes I made to them are:
>  - i.e. implement Collection.stream, Colleciton.addAll(Stream) and
> similar methods in Map.
> 
> Peter
> 
> ----------------------------------------
> preilly at mint-Precision-M6400
> ~/Public/hg/lambda/jdk/src/share/classes/java/util $ hg diff .
> diff -r ee96d823b92c src/share/classes/java/util/AbstractCollection.java
> --- a/src/share/classes/java/util/AbstractCollection.java       Fri
> Sep 14 16:46:42 2012 -0700
> +++ b/src/share/classes/java/util/AbstractCollection.java       Thu
> Sep 20 12:09:48 2012 +0100
> @@ -25,6 +25,8 @@
> 
>  package java.util;
> 
> +import java.util.streams.*;
> +
>  /**
>   * This class provides a skeletal implementation of the <tt>Collection</tt>
>   * interface, to minimize the effort required to implement this interface. <p>
> @@ -75,6 +77,10 @@
>       */
>      public abstract Iterator<E> iterator();
> 
> +    public Stream<E> stream() {
> +        return null;
> +    }
> +
>      public abstract int size();
> 
>      /**
> @@ -345,7 +351,9 @@
>                  modified = true;
>          return modified;
>      }
> -
> +    public void addAll(Stream<? extends E> c) {
> +//         return false;
> +    }
>      /**
>       * {@inheritDoc}
>       *
> diff -r ee96d823b92c src/share/classes/java/util/AbstractMap.java
> --- a/src/share/classes/java/util/AbstractMap.java      Fri Sep 14
> 16:46:42 2012 -0700
> +++ b/src/share/classes/java/util/AbstractMap.java      Thu Sep 20
> 12:09:48 2012 +0100
> @@ -25,6 +25,8 @@
> 
>  package java.util;
>  import java.util.Map.Entry;
> +import java.util.streams.*;
> +import java.util.functions.BiBlock;
> 
>  /**
>   * This class provides a skeletal implementation of the <tt>Map</tt>
> @@ -66,6 +68,10 @@
>   */
> 
>  public abstract class AbstractMap<K,V> implements Map<K,V> {
> +    public MapIterator<K,V> iterator() { return null; }
> +    public MapStream<K,V> stream() { return null; }
> +    public void forEach(BiBlock<? super K, ? super V> block) {}
> +    public void addAll(MapStream<? extends K, ? extends V> stream) {}
>      /**
>       * Sole constructor.  (For invocation by subclass constructors, typically
>       * implicit.)
> 
> 
> On Thu, Sep 20, 2012 at 11:31 AM, Aleksey Shipilev
> <aleksey.shipilev at oracle.com> wrote:
>> Hi Peter,
>>
>> On 09/20/2012 01:37 PM, Peter Reilly wrote:
>>> However, while attempting to compile some current code with the jdk8 compiler,
>>> there were a small number of issues with code that implements some java.util
>>> interfaces. The two that my code had problems with were Collection and Map.
>>
>> Can you provide a more concrete example? Was that your custom
>> collections were failing to compile against JDK8?
>>
>>> I worked around this by compiling a custom version of lamdba with the
>>> missing methods getting default implementation in
>>> j.u.AbstractCollection and j.u.AbstractMap.
>>
>> Aha, so your collections were implementing Collection, but not extending
>> AbstractCollection? Which methods you had to add? I see most of the new
>> methods have defaults in Collection.
>>
>> -Aleksey.
>>
>>
>>