org.gradoop.common.model.impl.id

Class GradoopId

java.lang.Object

org.gradoop.common.model.impl.id.GradoopId

All Implemented Interfaces:

Serializable, Comparable<GradoopId>, org.apache.flink.core.io.IOReadableWritable, org.apache.flink.types.CopyableValue<GradoopId>, org.apache.flink.types.Key<GradoopId>, org.apache.flink.types.NormalizableKey<GradoopId>, org.apache.flink.types.Value

public class GradoopId
extends Object
implements org.apache.flink.types.NormalizableKey<GradoopId>, org.apache.flink.types.CopyableValue<GradoopId>

Primary key for an EPGM element.

This implementation reuses much of the code of BSON's ObjectId (org.bson.types.ObjectId) to guarantee uniqueness. Much of the code is copied directly or has only small changes.

See Also:

references to: org.bson.types.ObjectId, Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static int	ID_SIZE Number of bytes to represent an id internally.
static GradoopId	NULL_VALUE Represents a null id.

Constructor Summary

Constructors

Constructor and Description
GradoopId() Required default constructor for instantiation by serialization logic.
GradoopId(int timestamp, int machineIdentifier, short processIdentifier, int counter) Creates a GradoopId using the given time, machine identifier, process identifier, and counter.

Method Summary

Modifier and Type	Method and Description
int	compareTo(GradoopId other) Performs a byte-wise comparison of this and the specified GradoopId.
GradoopId	copy()
void	copy(org.apache.flink.core.memory.DataInputView source, org.apache.flink.core.memory.DataOutputView target)
void	copyNormalizedKey(org.apache.flink.core.memory.MemorySegment target, int offset, int len)
void	copyTo(GradoopId target)
boolean	equals(Object o) Checks if the specified object is equal to the current id.
static GradoopId	fromByteArray(byte[] bytes) Returns the Gradoop ID represented by a byte array
static GradoopId	fromString(String string) Returns the Gradoop ID represented by a specified hexadecimal string.
static GradoopId	get() Returns a new GradoopId
int	getBinaryLength()
int	getMaxNormalizedKeyLen()
int	hashCode() Returns the hash code of this GradoopId.
static boolean	isValid(String hexString) Checks if a string can be transformed into a GradoopId.
static GradoopId	min(GradoopId first, GradoopId second) Compares the given GradoopIds and returns the smaller one.
void	read(org.apache.flink.core.memory.DataInputView in)
byte[]	toByteArray() Returns byte representation of a GradoopId
String	toString() Returns hex string representation of a GradoopId.
void	write(org.apache.flink.core.memory.DataOutputView out)

Methods inherited from class java.lang.Object

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

Field Detail

ID_SIZE

public static final int ID_SIZE

Number of bytes to represent an id internally.

See Also:

Constant Field Values

NULL_VALUE

public static final GradoopId NULL_VALUE

Represents a null id.

Constructor Detail

GradoopId

public GradoopId()

Required default constructor for instantiation by serialization logic.

GradoopId

public GradoopId(int timestamp,
                 int machineIdentifier,
                 short processIdentifier,
                 int counter)

Creates a GradoopId using the given time, machine identifier, process identifier, and counter.

Note: Implementation taken from org.bson.types.ObjectId

Parameters:

timestamp - the time in seconds

machineIdentifier - the machine identifier

processIdentifier - the process identifier

counter - the counter

Throws:

IllegalArgumentException - if the high order byte of machineIdentifier or counter is not zero

Method Detail

get

public static GradoopId get()

Returns a new GradoopId

Returns:

new GradoopId

fromString

public static GradoopId fromString(String string)

Returns the Gradoop ID represented by a specified hexadecimal string.

Note: Implementation taken from org.bson.types.ObjectId

Parameters:

string - hexadecimal GradoopId representation

Returns:

GradoopId

isValid

public static boolean isValid(String hexString)

Checks if a string can be transformed into a GradoopId.

Note: Implementation taken from org.bson.types.ObjectId

Parameters:

hexString - a potential GradoopId as a String.

Returns:

whether the string could be an object id

Throws:

IllegalArgumentException - if hexString is null

fromByteArray

public static GradoopId fromByteArray(byte[] bytes)

Returns the Gradoop ID represented by a byte array

Parameters:

bytes - byte representation

Returns:

Gradoop ID

toByteArray

public byte[] toByteArray()

Returns byte representation of a GradoopId

Returns:

Byte representation

equals

public boolean equals(Object o)

Checks if the specified object is equal to the current id.

Specified by:

equals in interface org.apache.flink.types.Key<GradoopId>

Overrides:

equals in class Object

Parameters:

o - the object to be compared

Returns:

true, iff the specified id is equal to this id

hashCode

public int hashCode()

Returns the hash code of this GradoopId.

Note: Implementation taken from org.bson.types.ObjectId

Specified by:

hashCode in interface org.apache.flink.types.Key<GradoopId>

Overrides:

hashCode in class Object

Returns:

hash code

compareTo

public int compareTo(GradoopId other)

Performs a byte-wise comparison of this and the specified GradoopId.

Specified by:

compareTo in interface Comparable<GradoopId>

Parameters:

other - the object to be compared.

Returns:

a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

toString

public String toString()

Returns hex string representation of a GradoopId.

Note: Implementation taken from org.bson.types.ObjectId

Overrides:

toString in class Object

Returns:

GradoopId string representation.

getMaxNormalizedKeyLen

public int getMaxNormalizedKeyLen()

Specified by:

getMaxNormalizedKeyLen in interface org.apache.flink.types.NormalizableKey<GradoopId>

copyNormalizedKey

public void copyNormalizedKey(org.apache.flink.core.memory.MemorySegment target,
                              int offset,
                              int len)

Specified by:

copyNormalizedKey in interface org.apache.flink.types.NormalizableKey<GradoopId>

write

public void write(org.apache.flink.core.memory.DataOutputView out)
           throws IOException

Specified by:

write in interface org.apache.flink.core.io.IOReadableWritable

Throws:

IOException

read

public void read(org.apache.flink.core.memory.DataInputView in)
          throws IOException

Specified by:

read in interface org.apache.flink.core.io.IOReadableWritable

Throws:

IOException

getBinaryLength

public int getBinaryLength()

Specified by:

getBinaryLength in interface org.apache.flink.types.CopyableValue<GradoopId>

copyTo

public void copyTo(GradoopId target)

Specified by:

copyTo in interface org.apache.flink.types.CopyableValue<GradoopId>

copy

public GradoopId copy()

Specified by:

copy in interface org.apache.flink.types.CopyableValue<GradoopId>

copy

public void copy(org.apache.flink.core.memory.DataInputView source,
                 org.apache.flink.core.memory.DataOutputView target)
          throws IOException

Specified by:

copy in interface org.apache.flink.types.CopyableValue<GradoopId>

Throws:

IOException

min

public static GradoopId min(GradoopId first,
                            GradoopId second)

Compares the given GradoopIds and returns the smaller one. It both are equal, the first argument is returned.

Parameters:

first - first GradoopId

second - second GradoopId

Returns:

smaller GradoopId or first if equal