FYI, "Updating JDK libraries to use Project Coin features"

["Zdeněk Troníček"]

Hi,

RefactoringNG can be used to update the code in batch.
For example, the following rule used in v0.3
(http://kenai.com/projects/refactoringng/downloads) will update the code
to the diamond operator:

NewClass {
    Expression [id: enclosing, nullable: true],
    List<Tree> [id: typeArgs],
    ParameterizedType {
        Expression [id: ident],
        List<Tree>
    },
    List<Expression> [id: args],
    Class [id: body, elementKind: CLASS, nullable: true]
} ->
NewClass {
    Expression [ref: enclosing],
    List<Tree> [ref: typeArgs],
    ParameterizedType {
        Expression [ref: ident],
        List<Tree> { }
    },
    List<Expression> [ref: args],
    Class [ref: body]
}

(NetBeans 7 throws NullPointerException, but it is not severe and you can
continue. In NetBeans 6, it is performed without any error.)

When trying this, I found inconsistency in javac's AST. In NewClassTree,
identifier is ExpressionTree:

public interface NewClassTree extends ExpressionTree {
    ExpressionTree getEnclosingExpression();
    List<? extends Tree> getTypeArguments();
    ExpressionTree getIdentifier();
    List<? extends ExpressionTree> getArguments();
    ClassTree getClassBody();
}

However, for new ArrayList<Integer>() the identifier is
ParameterizedTypeTree which is not ExpressionTree:

public interface ParameterizedTypeTree extends Tree {
    Tree getType();
    List<? extends Tree> getTypeArguments();
}

Z.T.
-- 
Zdenek Tronicek
FIT CTU in Prague


Joe Darcy napsal(a):
> Hello.
>
> FYI, we'll soon start a process to systematically update the JDK
> libraries to use Project Coin features:
>
> http://mail.openjdk.java.net/pipermail/jdk7-dev/2010-December/001727.html
>
> -Joe
>
>