Package org.rocksdb

Class OptionsUtil

java.lang.Object

org.rocksdb.OptionsUtil

public class OptionsUtil
extends Object

Method Summary

Modifier and Type	Method	Description
static String	getLatestOptionsFileName(String dbPath, Env env)	Returns the latest options file name under the specified RocksDB path.
static void	loadLatestOptions(ConfigOptions configOptions, String dbPath, DBOptions dbOptions, List<ColumnFamilyDescriptor> cfDescs)	A static method to construct the DBOptions and ColumnFamilyDescriptors by loading the latest RocksDB options file stored in the specified rocksdb database.
static void	loadOptionsFromFile(ConfigOptions configOptions, String optionsFileName, DBOptions dbOptions, List<ColumnFamilyDescriptor> cfDescs)	Similar to LoadLatestOptions, this function constructs the DBOptions and ColumnFamilyDescriptors based on the specified RocksDB Options file.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

loadLatestOptions

public static void loadLatestOptions(ConfigOptions configOptions,
 String dbPath,
 DBOptions dbOptions,
 List<ColumnFamilyDescriptor> cfDescs)
                              throws RocksDBException

A static method to construct the DBOptions and ColumnFamilyDescriptors by loading the latest RocksDB options file stored in the specified rocksdb database.

Note that the all the pointer options (except table_factory, which will be described in more details below) will be initialized with the default values. Developers can further initialize them after this function call. Below is an example list of pointer options which will be initialized.

- env - memtable_factory - compaction_filter_factory - prefix_extractor - comparator - merge_operator - compaction_filter

For table_factory, this function further supports deserializing BlockBasedTableFactory and its BlockBasedTableOptions except the pointer options of BlockBasedTableOptions (flush_block_policy_factory, and block_cache), which will be initialized with default values. Developers can further specify these three options by casting the return value of TableFactoroy::GetOptions() to BlockBasedTableOptions and making necessary changes.

Parameters:

configOptions - ConfigOptions instance.

dbPath - the path to the RocksDB.

dbOptions - DBOptions instance. This will be filled and returned.

cfDescs - A list of ColumnFamilyDescriptor's be returned.

Throws:

RocksDBException - thrown if error happens in underlying native library.

loadOptionsFromFile

public static void loadOptionsFromFile(ConfigOptions configOptions,
 String optionsFileName,
 DBOptions dbOptions,
 List<ColumnFamilyDescriptor> cfDescs)
                                throws RocksDBException

Similar to LoadLatestOptions, this function constructs the DBOptions and ColumnFamilyDescriptors based on the specified RocksDB Options file. See LoadLatestOptions above.

Parameters:

configOptions - ConfigOptions instance.

optionsFileName - the RocksDB options file path.

dbOptions - DBOptions instance. This will be filled and returned.

cfDescs - A list of ColumnFamilyDescriptor's be returned.

Throws:

RocksDBException - thrown if error happens in underlying native library.

getLatestOptionsFileName

public static String getLatestOptionsFileName(String dbPath,
 Env env)
                                       throws RocksDBException

Returns the latest options file name under the specified RocksDB path.

Parameters:

dbPath - the path to the RocksDB.

env - Env instance.

Returns:

the latest options file name under the db path.

Throws:

RocksDBException - thrown if error happens in underlying native library.