Package me.ahoo.cosid.snowflake

Class SecondSnowflakeId

java.lang.Object

me.ahoo.cosid.snowflake.AbstractSnowflakeId

me.ahoo.cosid.snowflake.SecondSnowflakeId

All Implemented Interfaces:

IdGenerator, SnowflakeId, Statistical, StringIdGenerator

public class SecondSnowflakeId
extends AbstractSnowflakeId

Second-based Snowflake ID generator.

Similar to MillisecondSnowflakeId but uses seconds instead of milliseconds as the time unit. This allows for a longer timestamp range but with lower time precision.

Default configuration:

• Timestamp bits: 31 (about 68 years with second precision)
• Machine ID bits: 10 (1024 unique machines)
• Sequence bits: 22 (about 4 million IDs per second per machine)

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_MACHINE_BIT	Default number of machine ID bits (10 bits).
static final int	DEFAULT_SEQUENCE_BIT	Default number of sequence bits (22 bits).
static final long	DEFAULT_SEQUENCE_RESET_THRESHOLD	Default sequence reset threshold (half of max sequence).
static final int	DEFAULT_TIMESTAMP_BIT	Default number of timestamp bits (31 bits).

Fields inherited from class me.ahoo.cosid.snowflake.AbstractSnowflakeId

epoch, lastTimestamp, machineBit, machineId, machineLeft, maxMachineId, maxSequence, maxTimestamp, sequence, sequenceBit, timestampBit, timestampLeft

Fields inherited from interface me.ahoo.cosid.snowflake.SnowflakeId

TOTAL_BIT

Constructor Summary

Constructors

Constructor	Description
SecondSnowflakeId(int machineId)	Creates a SecondSnowflakeId with default configuration.
SecondSnowflakeId(int machineBit, int machineId)	Creates a SecondSnowflakeId with custom machine bits.
SecondSnowflakeId(long epoch, int timestampBit, int machineBit, int sequenceBit, int machineId)	Creates a SecondSnowflakeId with custom bit configuration.
SecondSnowflakeId(long epoch, int timestampBit, int machineBit, int sequenceBit, int machineId, long sequenceResetThreshold)	Creates a SecondSnowflakeId with full custom configuration.

Method Summary

Modifier and Type	Method	Description
protected long	getCurrentTime()	Gets the current time in the appropriate unit for this snowflake ID variant.

Methods inherited from class me.ahoo.cosid.snowflake.AbstractSnowflakeId

generate, getEpoch, getLastTimestamp, getMachineBit, getMachineId, getMaxMachineId, getMaxSequence, getMaxTimestamp, getSequenceBit, getTimestampBit, nextTime

Methods inherited from class java.lang.Object

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

Methods inherited from interface me.ahoo.cosid.IdGenerator

generateAsString, idConverter

Methods inherited from interface me.ahoo.cosid.snowflake.SnowflakeId

isSafeJavascript, stat

Field Details

DEFAULT_TIMESTAMP_BIT

public static final int DEFAULT_TIMESTAMP_BIT

Default number of timestamp bits (31 bits).

See Also:

• Constant Field Values

DEFAULT_MACHINE_BIT

public static final int DEFAULT_MACHINE_BIT

Default number of machine ID bits (10 bits).

See Also:

• Constant Field Values

DEFAULT_SEQUENCE_BIT

public static final int DEFAULT_SEQUENCE_BIT

Default number of sequence bits (22 bits).

See Also:

• Constant Field Values

DEFAULT_SEQUENCE_RESET_THRESHOLD

public static final long DEFAULT_SEQUENCE_RESET_THRESHOLD

Default sequence reset threshold (half of max sequence).

See Also:

• Constant Field Values

Constructor Details

SecondSnowflakeId

public SecondSnowflakeId(int machineId)

Creates a SecondSnowflakeId with default configuration.

Parameters:

machineId - the machine ID

SecondSnowflakeId

public SecondSnowflakeId(int machineBit,
 int machineId)

Creates a SecondSnowflakeId with custom machine bits.

Parameters:

machineBit - the number of bits for machine ID

machineId - the machine ID

SecondSnowflakeId

public SecondSnowflakeId(long epoch,
 int timestampBit,
 int machineBit,
 int sequenceBit,
 int machineId)

Creates a SecondSnowflakeId with custom bit configuration.

Parameters:

epoch - epoch timestamp in milliseconds

timestampBit - number of bits for timestamp

machineBit - number of bits for machine ID

sequenceBit - number of bits for sequence

machineId - the machine ID

SecondSnowflakeId

public SecondSnowflakeId(long epoch,
 int timestampBit,
 int machineBit,
 int sequenceBit,
 int machineId,
 long sequenceResetThreshold)

Creates a SecondSnowflakeId with full custom configuration.

Parameters:

epoch - epoch timestamp in milliseconds

timestampBit - number of bits for timestamp

machineBit - number of bits for machine ID

sequenceBit - number of bits for sequence

machineId - the machine ID

sequenceResetThreshold - threshold for resetting sequence

Method Details

getCurrentTime

protected long getCurrentTime()

Description copied from class: AbstractSnowflakeId

Gets the current time in the appropriate unit for this snowflake ID variant.

Specified by:

getCurrentTime in class AbstractSnowflakeId

Returns:

current time value