Oracle JDK 今天发布两个更新版本，分别是 6.0 的第三十个更新以及 7.0 的第二个更新版本。
其中 6u30 的改进记录：
1. New entries were added to the blacklist of vulnerable applications.
2. Several critical security issues were fixed.
3. JIT and loop bugs were fixed.
4. An SSL/TLS regression was fixed.
5. An enhanced Java VisualVM is included in the package.
6. Gervill, a new software synthesizer implementation, was integrated.
7. Olson time zone data was updated to version 2011
7u2 的改进记录：
1. The footprint of signed JAR files was reduced.
2. Caching of network content for application code running in Web Start mode is now enabled by default.
3. Handling of content with gzip encoding was improved.
4. Several other minor improvements and bugfixes were made.
5. Olson time zone data was updated to version 2011