Package org.apache.hadoop.hdfs.server.federation.store.records

Class BaseRecord

java.lang.Object

org.apache.hadoop.hdfs.server.federation.store.records.BaseRecord

All Implemented Interfaces:

java.lang.Comparable<BaseRecord>

Direct Known Subclasses:

DisabledNameservice, MembershipState, MembershipStats, MountTable, RouterState, StateStoreVersion

public abstract class BaseRecord
extends java.lang.Object
implements java.lang.Comparable<BaseRecord>

Abstract base of a data record in the StateStore. All StateStore records are derived from this class. Data records are persisted in the data store and are identified by their primary key. Each data record contains:

• A primary key consisting of a combination of record data fields.
• A modification date.
• A creation date.

Field Summary

Fields

Modifier and Type	Field	Description
static java.lang.String	ERROR_MSG_CREATION_TIME_NEGATIVE
static java.lang.String	ERROR_MSG_MODIFICATION_TIME_NEGATIVE

Constructor Summary

Constructors

Constructor	Description
BaseRecord()

Method Summary

Modifier and Type	Method	Description
boolean	checkExpired(long currentTime)	Called when the modification time and current time is available, checks for expirations.
int	compareTo(BaseRecord record)
boolean	equals(java.lang.Object obj)	Override equals check to use primary key(s) for comparison.
protected static java.lang.String	generateMashupKey(java.util.Map<java.lang.String,java.lang.String> keys)	Generates a cache key from a map of values.
abstract long	getDateCreated()	Get the creation time for the record.
abstract long	getDateModified()	Get the modification time for the record.
long	getDeletionMs()	Get the deletion time for the expired record.
abstract long	getExpirationMs()	Get the expiration time for the record.
java.lang.String	getPrimaryKey()	Join the primary keys into one single primary key.
abstract java.util.Map<java.lang.String,java.lang.String>	getPrimaryKeys()	Map of primary key names to values for the record.
int	hashCode()	Override hash code to use primary key(s) for comparison.
boolean	hasOtherFields()	If the record has fields others than the primary keys.
void	init()	Initialize the object.
boolean	isExpired()	Check if this record is expired.
boolean	like(BaseRecord other)	Check if this record matches a partial record.
abstract void	setDateCreated(long time)	Set the creation time for the record.
abstract void	setDateModified(long time)	Set the modification time for the record.
boolean	shouldBeDeleted(long currentTime)	Called when this record is expired and expired deletion is enabled, checks for the deletion.
java.lang.String	toString()
void	validate()	Validates the record.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

ERROR_MSG_CREATION_TIME_NEGATIVE

public static final java.lang.String ERROR_MSG_CREATION_TIME_NEGATIVE

See Also:

Constant Field Values

ERROR_MSG_MODIFICATION_TIME_NEGATIVE

public static final java.lang.String ERROR_MSG_MODIFICATION_TIME_NEGATIVE

See Also:

Constant Field Values

Constructor Detail

BaseRecord

public BaseRecord()

Method Detail

setDateModified

public abstract void setDateModified(long time)

Set the modification time for the record.

Parameters:

time - Modification time of the record.

getDateModified

public abstract long getDateModified()

Get the modification time for the record.

Returns:

Modification time of the record.

setDateCreated

public abstract void setDateCreated(long time)

Set the creation time for the record.

Parameters:

time - Creation time of the record.

getDateCreated

public abstract long getDateCreated()

Get the creation time for the record.

Returns:

Creation time of the record

getExpirationMs

public abstract long getExpirationMs()

Get the expiration time for the record.

Returns:

Expiration time for the record.

isExpired

public boolean isExpired()

Check if this record is expired. The default is false. Override for customized behavior.

Returns:

True if the record is expired.

getDeletionMs

public long getDeletionMs()

Get the deletion time for the expired record. The default is disabled. Override for customized behavior.

Returns:

Deletion time for the expired record.

getPrimaryKeys

public abstract java.util.Map<java.lang.String,java.lang.String> getPrimaryKeys()

Map of primary key names to values for the record. The primary key can be a combination of 1-n different State Store serialized values.

Returns:

Map of key/value pairs that constitute this object's primary key.

init

public void init()

Initialize the object.

getPrimaryKey

public java.lang.String getPrimaryKey()

Join the primary keys into one single primary key.

Returns:

A string that is guaranteed to be unique amongst all records of this type.

hasOtherFields

@VisibleForTesting
public boolean hasOtherFields()

If the record has fields others than the primary keys. This is used by TestStateStoreDriverBase to skip the modification check.

Returns:

If the record has more fields.

generateMashupKey

protected static java.lang.String generateMashupKey(java.util.Map<java.lang.String,java.lang.String> keys)

Generates a cache key from a map of values.

Parameters:

keys - Map of values.

Returns:

String mashup of key values.

like

public boolean like(BaseRecord other)

Check if this record matches a partial record.

Parameters:

other - Partial record.

Returns:

If this record matches.

equals

public boolean equals(java.lang.Object obj)

Override equals check to use primary key(s) for comparison.

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Override hash code to use primary key(s) for comparison.

Overrides:

hashCode in class java.lang.Object

compareTo

public int compareTo(BaseRecord record)

Specified by:

compareTo in interface java.lang.Comparable<BaseRecord>

checkExpired

public boolean checkExpired(long currentTime)

Called when the modification time and current time is available, checks for expirations.

Parameters:

currentTime - The current timestamp in ms from the data store, to be compared against the modification and creation dates of the object.

Returns:

boolean True if the record has been updated and should be committed to the data store. Override for customized behavior.

shouldBeDeleted

public boolean shouldBeDeleted(long currentTime)

Called when this record is expired and expired deletion is enabled, checks for the deletion. If an expired record exists beyond the deletion time, it should be deleted.

Parameters:

currentTime - The current timestamp in ms from the data store, to be compared against the modification and creation dates of the object.

Returns:

boolean True if the record has been updated and should be deleted from the data store.

validate

public void validate()

Validates the record. Called when the record is created, populated from the state store, and before committing to the state store. If validate failed, there throws an exception.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object