Summary:
1. Move disOwnNativeHandle() function from RocksDB to RocksObject
to allow other RocksObject to use disOwnNativeHandle() when its
ownership of native handle has been transferred.

2. RocksObject now has an abstract implementation of dispose(),
which does the following two things.  First, it checks whether
both isOwningNativeHandle() and isInitialized() return true.
If so, it will call the protected abstract function dispose0(),
which all the subclasses of RocksObject should implement.  Second,
it sets nativeHandle_ = 0.  This redesign ensure all subclasses
of RocksObject have the same dispose behavior.

3. All subclasses of RocksObject now should implement dispose0()
instead of dispose(), and dispose0() will be called only when
isInitialized() returns true.

Test Plan:
make rocksdbjava
make jtest

Reviewers: dhruba, sdong, ankgup87, rsumbaly, swapnilghike, zzbennett, haobo

Reviewed By: haobo

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D18801

Summary:
Originally, the boolean arguments in Java DB benchmark only takes
true and false as valid input.  This diff allows boolean arguments
to be set using 0 or 1.

Test Plan:
make rocksdbjava
make jdb_bench
java/jdb_bench.sh --db=/tmp/path-not-exist --use_existing_db=1
java/jdb_bench.sh --db=/tmp/path-not-exist --use_existing_db=0
java/jdb_bench.sh --db=/tmp/path-not-exist --use_existing_db=1

Reviewers: haobo, dhruba, sdong, ankgup87, rsumbaly, swapnilghike, zzbennett

Reviewed By: haobo

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D18687

Give BackupableDB sole responsibility of the native
object to prevent RocksDB from also trying to delete
it.

Summary: Fixed a bug in Java DB Benchmark where random reads does not consider full key range.

Test Plan:
make rocksdbjava
make jdb_bench
cd java
jdb_bench.sh --db=/tmp/rocksdb-test --benchmarks=fillseq --use_existing_db=false --num=100000
jdb_bench.sh --db=/tmp/rocksdb-test --benchmarks=readrandom --use_existing_db=true --num=100000 --reads=1000000

Reviewers: haobo, sdong

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18693

Summary: Make read benchmarks print out found / not-found information.

Test Plan:
make rocksdbjava
make jdb_bench
cd java
./jdb_bench.sh

Reviewers: haobo, sdong

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18699

Summary:
Before the Java binding for Env is ready, Java developers have no way to
control the number of background threads.  This diff provides a temporary
solution where RocksDB.setMaxBackgroundCompactions() will affect the
number of background threads.

Note that once Env is ready.  Changes made in this diff should be reverted.

Test Plan:
make rocksdbjava
make jtest
make jdb_bench
java/jdb_bench.sh

Reviewers: haobo, sdong

Reviewed By: sdong

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18681

Summary:
Renamed Iterator to RocksIterator to avoid potential confliction with
the Java built-in Iterator.

Test Plan:
make rocksdbjava
make jtest

Reviewers: haobo, dhruba, sdong, ankgup87

Reviewed By: sdong

CC: leveldb, rsumbaly, swapnilghike, zzbennett

Differential Revision: https://reviews.facebook.net/D18615

Summary:
Add RocksObject, the base class of all java objects which has a c++ pointer.
While the finalizer of a RocksObject will release its c++ resource, it is
suggested to call its RocksObject.dispose() to manually release its
c++ resource.

Existing RocksDB java classes are now extending RocksObject.

Test Plan:
make rocksdbjava
make jtest
make jdb_bench

Reviewers: haobo, dhruba, sdong, ankgup87, rsumbaly, swapnilghike, zzbennett

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18411

Summary:
Add static method RocksDB.loadLibrary() which loads necessary library
files.

Test Plan:
make rocksdbjava
make jtest
make jdb_bench
java/jdb_bench.sh

Reviewers: haobo, dhruba, sdong, ankgup87, rsumbaly, swapnilghike, zzbennett

Reviewed By: ankgup87

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18375

[Java] Fixed compile error due to the removal of ReadOptions.prefix_seek, minor improvement on DbBenchmark.java.

[Java] Enable filluniquerandom, readseq, BloomFilter, and 70+ command-line options to DbBenchmark.java

Summary:
* Add filluniquerandom
* Add readseq, implemented using iterator.
* Realize most command-line-arguments from db_bench.cc (70+).
* Some code are commented out as some of the options in Options
  not yet have Java bindings.
* Add default option to DbBenchmark.
* RocksDB will now take the ownership of all c++ raw-pointers from Options, which includes a c++ raw-pointer for Filter.

Test Plan: ./jdb_bench.sh --db=/tmp/rocksjava-bench/db --num_levels=6 --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 --block_size=4096 --cache_size=17179869184 --cache_numshardbits=6 --compression_ratio=1 --min_level_to_compress=-1 --disable_seek_compaction=1 --hard_rate_limit=2 --write_buffer_size=134217728 --max_write_buffer_number=2 --level0_file_num_compaction_trigger=8 --target_file_size_base=134217728 --max_bytes_for_level_base=1073741824 --disable_wal=0 --wal_dir=/tmp/rocksjava-bench/wal --sync=0 --disable_data_sync=1 --verify_checksum=1 --delete_obsolete_files_period_micros=314572800 --max_grandparent_overlap_factor=10 --max_background_compactions=4 --max_background_flushes=0 --level0_slowdown_writes_trigger=16 --level0_stop_writes_trigger=24 --statistics=0 --stats_per_interval=0 --stats_interval=1048576 --histogram=0 --use_plain_table=1 --open_files=-1 --mmap_read=1 --mmap_write=0 --memtablerep=prefix_hash --bloom_bits=10 --bloom_locality=1 --perf_level=0 --benchmarks=filluniquerandom,readseq,readrandom --use_existing_db=0 --threads=4

Reviewers: haobo, dhruba, sdong, ankgup87, rsumbaly, swapnilghike, zzbennett

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18267

Summary:
Add Java bindings and Java tests for 30+ rocksdb::Options.  Codes are
machine-genearted based on include/rocksdb/options.h with manual-polishment.

Test Plan:
make rocksdbjava
make jtest

Reviewers: haobo, dhruba, sdong, ankgup87, rsumbaly, swapnilghike, zzbennett

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18273

Summary: Add Java binding and test for rocksdb::ReadOptions.

Test Plan:
make rocksdbjava
make jtest

Reviewers: haobo, dhruba, sdong, ankgup87, rsumbaly, swapnilghike, zzbennett

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18129

Summary:
Add Java bindings for memtables and sst format.  Specifically,
add two abstract Java classses --- MemTableConfig and SstFormatConfig.
Each MemTable / SST implementation should has its own config class
extends MemTableConfig / SstFormatConfig respectively and pass it
to Options via setMemTableConfig / setSstConfig.

Test Plan:
make rocksdbjava
make jdb_test
make jdb_bench
java/jdb_bench.sh \
  --benchmarks=fillseq,readrandom,readwhilewriting \
  --memtablerep=hash_skiplist \
  --use_plain_table=1 \
  --key_size=20 \
  --prefix_size=12 \
  --value_size=100 \
  --cache_size=17179869184 \
  --disable_wal=0 \
  --sync=0 \

Reviewers: haobo, ankgup87, sdong

Reviewed By: haobo

CC: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D17997