code review request for 6880112, Coin: use diamond in core libraries

Stuart Marks stuart.marks at
Thu Dec 16 00:24:32 UTC 2010

Hi all,

As Joe Darcy mentioned yesterday [1], I'm working on updating the JDK libraries 
to use the new JDK 7 Coin features. The first feature is the diamond operator 
[2]. This first round of changes includes java.lang,, java.sql, 
java.util, their corresponding tests, and related implementation files 
(exclusive of java.util.concurrent and related files). This change touches a 
total of 71 files. This is rather a lot of files, but the changes are all 
one-liners, and most files have only a few changes.

Lance, please review the change to src/share/classes/java/sql/

Joe, Alan, please review the rest of the changes.

For the curious, I'm using a Jackpot-based automated converter to make bulk 
changes to large numbers of source files. I plan to do diamond conversion of a 
few other groups of JDK library packages before moving on to other Coin features.

For verification, it turns out that diamond conversion doesn't change the 
bytecodes that are emitted by the compiler, so the resulting class files are 
byte-for-byte identical to class files from before the change. This should make 
us pretty confident that the changes don't break anything. Unfortunately, other 
Coin features will change bytecodes, so we won't be able to use this easy 
verification technique when we apply other Coin features.

The webrev is here:

A mercurial bundle suitable for "hg unbundle" is here:





More information about the core-libs-dev mailing list