Avoid the pattern where a Random object is allocated, used once or twice, and
then left for GC. This pattern triggers warnings from some static analysis tools
because this pattern leads to poor effective randomness. In a few cases we were
legitimately suffering from this issue; in others a change is still good to
reduce noise in analysis results.
Use ThreadLocalRandom where there is no requirement to set the seed to gain
good reuse.
Where useful relax use of SecureRandom to simply Random or ThreadLocalRandom,
which are unlikely to block if the system entropy pool is low, if we don't need
crypographically strong randomness for the use case. The exception to this is
normalization of use of Bytes#random to fill byte arrays with randomness.
Because Bytes#random may be used to generate key material it must be backed by
SecureRandom.
Signed-off-by: Duo Zhang <zhangduo@apache.org>
Includes partial backport of hbase-build-configuration module
Signed-off-by: Michael Stack <stack@apache.org>
Signed-off-by: Misty Stanley-Jones <misty@apache.org>
Pull in guava 22.0 by using the shaded version up in new hbase-thirdparty project.
In poms, exclude guava everywhere except on hadoop-common. Do this so
we minimize transitive includes. hadoop-common is needed because hadoop
Configuration uses guava doing preconditions.
Everywhere we used guava, instead use shaded so fix a load of imports.
Stopwatch API changed as did hashing and toStringHelper which is now
in MoreObjects class. Otherwise, minimal changes to come up on 22.0
