Major Description
org.apache.derby.jdbc.EmbeddedDataSource.findDriver() uses the
double-checked-locking idiom for setting the 'driver' variable. This
idiom is, however, not correct and hence the code is broken. The fix
is to remove the outer if, i.e. to always enter the synchronized block.
See also
http://www.cs.umd.edu/~pugh/java/memoryModel/DoubleCheckedLocking.html