Record Class ConfigChange

java.lang.Object

java.lang.Record

com.loomcache.server.consensus.ConfigChange

Record Components:

type - the change type (non-null: ADD_SERVER, REMOVE_SERVER, LEARNER_ADD, LEARNER_REMOVE)

nodeId - the target node ID (non-null, non-blank)

address - the node address (non-blank for ADD_SERVER and LEARNER_ADD)

public record ConfigChange(ConfigChange.Type type, String nodeId, @Nullable String address)
extends Record

Represents a single serialized membership-change command in the Raft cluster.

This record carries the intent that is stored in a CONFIG_CHANGE log entry. It does not, by itself, provide any membership-safety guarantees. Safety properties such as "one change at a time", learner catch-up before promotion, and which quorum must commit the entry are enforced by the caller that submits and applies the change.

Since:

1.0

See Also:

• LogEntry
• RaftNode.submitConfigChange(ConfigChange)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	ConfigChange.Type

Constructor Summary

Constructors

Constructor	Description
ConfigChange(ConfigChange.Type type, String nodeId, @Nullable String address)	Compact constructor for validation.

Method Summary

Modifier and Type	Method	Description
@Nullable String	address()	Returns the value of the address record component.
static ConfigChange	deserialize(byte[] data)	Deserialize a ConfigChange from a byte array.
final boolean	equals(Object o)	Indicates whether some other object is "equal to" this one.
final int	hashCode()	Returns a hash code value for this object.
boolean	isAddServer()
static boolean	isConfigChange(byte[] data)	Check if a byte array carries the ConfigChange header.
boolean	isLearnerAdd()
boolean	isLearnerRemove()
boolean	isRemoveServer()
String	nodeId()	Returns the value of the nodeId record component.
byte[]	serialize()	Serialize to byte array for storage in Raft log.
final String	toString()	Returns a string representation of this record class.
ConfigChange.Type	type()	Returns the value of the type record component.

Methods inherited from class Object

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

Constructor Details

ConfigChange

public ConfigChange(ConfigChange.Type type,
 String nodeId,
 @Nullable String address)

Compact constructor for validation. Ensures type is non-null, nodeId is non-null and non-blank, and address is non-blank for ADD_SERVER and LEARNER_ADD operations.

Throws:

NullPointerException - if type or nodeId is null

IllegalArgumentException - if nodeId is blank or address is invalid

Method Details

isAddServer

public boolean isAddServer()

isRemoveServer

public boolean isRemoveServer()

isLearnerAdd

public boolean isLearnerAdd()

isLearnerRemove

public boolean isLearnerRemove()

serialize

public byte[] serialize()

Serialize to byte array for storage in Raft log. Format: 4 bytes (magic) + 1 byte (type) + 4 bytes (nodeId length) + nodeId bytes + 4 bytes (address length) + address bytes

Returns:

non-null serialized byte array

isConfigChange

public static boolean isConfigChange(byte[] data)

Check if a byte array carries the ConfigChange header.

Parameters:

data - the data to check

Returns:

true if data contains the ConfigChange magic header

deserialize

public static ConfigChange deserialize(byte[] data)

Deserialize a ConfigChange from a byte array.

Parameters:

data - the serialized data (non-null)

Returns:

a new ConfigChange instance

Throws:

NullPointerException - if data is null

IllegalArgumentException - if data format is invalid

toString

public final String toString()

Returns a string representation of this record class. The representation contains the name of the class, followed by the name and value of each of the record components.

Specified by:

toString in class Record

Returns:

a string representation of this object

hashCode

public final int hashCode()

Returns a hash code value for this object. The value is derived from the hash code of each of the record components.

Specified by:

hashCode in class Record

Returns:

a hash code value for this object

equals

public final boolean equals(Object o)

Indicates whether some other object is "equal to" this one. The objects are equal if the other object is of the same class and if all the record components are equal. All components in this record class are compared with Objects::equals(Object,Object).

Specified by:

equals in class Record

Parameters:

o - the object with which to compare

Returns:

true if this object is the same as the o argument; false otherwise.

type

public ConfigChange.Type type()

Returns the value of the type record component.

Returns:

the value of the type record component

nodeId

public String nodeId()

Returns the value of the nodeId record component.

Returns:

the value of the nodeId record component

address

public @Nullable String address()

Returns the value of the address record component.

Returns:

the value of the address record component