VectorClock (Hazelcast Root 3.11 API)

java.lang.Object
- com.hazelcast.cluster.impl.VectorClock

All Implemented Interfaces:

DataSerializable, IdentifiedDataSerializable
```
public class VectorClock
extends Object
implements IdentifiedDataSerializable
```
Vector clock consisting of distinct replica logical clocks.
See https://en.wikipedia.org/wiki/Vector_clock The vector clock may be read from different thread but concurrent updates must be synchronized externally. There is no guarantee for concurrent updates.

Constructor Summary

Constructors
Constructor and Description

VectorClock()

VectorClock(VectorClock from)

Constructors
Constructor and Description
`VectorClock()`
`VectorClock(VectorClock from)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`Set<Map.Entry<String,Long>>`	`entrySet()` Returns a set of replica logical timestamps for this vector clock.
`boolean`	`equals(Object o)`
`int`	`getFactoryId()` Returns DataSerializableFactory factory ID for this class.
`int`	`getId()` Returns type identifier for this class.
`Long`	`getTimestampForReplica(String replicaId)` Returns logical timestamp for given `replicaId`.
`int`	`hashCode()`
`boolean`	`isAfter(VectorClock other)` Returns `true` if this vector clock is causally strictly after the provided vector clock.
`boolean`	`isEmpty()` Returns `true` if this vector clock is empty (there are no logical timestamps for any replica).
`void`	`merge(VectorClock other)` Merges the provided vector clock into this one by taking the maximum of the logical timestamps for each replica.
`void`	`readData(ObjectDataInput in)` Reads fields from the input stream
`void`	`setReplicaTimestamp(String replicaId, long timestamp)` Sets the logical timestamp for the given `replicaId`.
`String`	`toString()`
`void`	`writeData(ObjectDataOutput out)` Writes object fields to output stream

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - VectorClock
```
public VectorClock()
```
  - VectorClock
```
public VectorClock(VectorClock from)
```
- Method Detail
  - getTimestampForReplica
```
public Long getTimestampForReplica(String replicaId)
```
    Returns logical timestamp for given replicaId. This method may be called from different threads and the result reflects the latest update on the vector clock.
  - setReplicaTimestamp
```
public void setReplicaTimestamp(String replicaId,
                                long timestamp)
```
    Sets the logical timestamp for the given replicaId. This method is not thread safe and concurrent access must be synchronized externally.
  - merge
```
public void merge(VectorClock other)
```
    Merges the provided vector clock into this one by taking the maximum of the logical timestamps for each replica. This method is not thread safe and concurrent access must be synchronized externally.
  - isAfter
```
public boolean isAfter(VectorClock other)
```
    Returns true if this vector clock is causally strictly after the provided vector clock. This means that it the provided clock is neither equal to, greater than or concurrent to this vector clock. This method may be called from different threads and the result reflects the latest update on the vector clock.
  - isEmpty
```
public boolean isEmpty()
```
    Returns true if this vector clock is empty (there are no logical timestamps for any replica). This method may be called from different threads and the result reflects the latest update on the vector clock.
  - entrySet
```
public Set<Map.Entry<String,Long>> entrySet()
```
    Returns a set of replica logical timestamps for this vector clock.
  - writeData
```
public void writeData(ObjectDataOutput out)
               throws IOException
```
    Description copied from interface: DataSerializable
    
    Writes object fields to output stream
    
    Specified by:
    
    writeData in interface DataSerializable
    
    Parameters:
    
    out - output
    
    Throws:
    
    IOException - if an I/O error occurs. In particular, an IOException may be thrown if the output stream has been closed.
  - readData
```
public void readData(ObjectDataInput in)
              throws IOException
```
    Description copied from interface: DataSerializable
    
    Reads fields from the input stream
    
    Specified by:
    
    readData in interface DataSerializable
    
    Parameters:
    
    in - input
    
    Throws:
    
    IOException - if an I/O error occurs. In particular, an IOException may be thrown if the input stream has been closed.
  - equals
```
public boolean equals(Object o)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - getFactoryId
```
public int getFactoryId()
```
    Description copied from interface: IdentifiedDataSerializable
    
    Returns DataSerializableFactory factory ID for this class.
    
    Specified by:
    
    getFactoryId in interface IdentifiedDataSerializable
    
    Returns:
    
    factory ID
  - getId
```
public int getId()
```
    Description copied from interface: IdentifiedDataSerializable
    
    Returns type identifier for this class. It should be unique per DataSerializableFactory.
    
    Specified by:
    
    getId in interface IdentifiedDataSerializable
    
    Returns:
    
    type ID

Class VectorClock

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

VectorClock

VectorClock

Method Detail

getTimestampForReplica

setReplicaTimestamp

merge

isAfter

isEmpty

entrySet

writeData

readData

equals

hashCode

toString

getFactoryId

getId