org.rocksdb

Enum EncodingType

java.lang.Object

java.lang.Enum<EncodingType>

org.rocksdb.EncodingType

All Implemented Interfaces:

Serializable, Comparable<EncodingType>

public enum EncodingType
extends Enum<EncodingType>

EncodingType

The value will determine how to encode keys when writing to a new SST file.

This value will be stored inside the SST file which will be used when reading from the file, which makes it possible for users to choose different encoding type when reopening a DB. Files with different encoding types can co-exist in the same DB and can be read.

Enum Constant Summary

Enum Constants

Enum Constant and Description
kPlain Always write full keys without any special encoding.
kPrefix Find opportunity to write the same prefix once for multiple rows.

Method Summary

Modifier and Type	Method and Description
byte	getValue() Returns the byte value of the enumerations value
static EncodingType	valueOf(String name) Returns the enum constant of this type with the specified name.
static EncodingType[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

kPlain

public static final EncodingType kPlain

Always write full keys without any special encoding.

kPrefix

public static final EncodingType kPrefix

Find opportunity to write the same prefix once for multiple rows. In some cases, when a key follows a previous key with the same prefix, instead of writing out the full key, it just writes out the size of the shared prefix, as well as other bytes, to save some bytes.

When using this option, the user is required to use the same prefix extractor to make sure the same prefix will be extracted from the same key. The Name() value of the prefix extractor will be stored in the file. When reopening the file, the name of the options.prefix_extractor given will be bitwise compared to the prefix extractors stored in the file. An error will be returned if the two don't match.

Method Detail

values

public static EncodingType[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (EncodingType c : EncodingType.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static EncodingType valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

getValue

public byte getValue()

Returns the byte value of the enumerations value

Returns:

byte representation