IDManager (JanusGraph-Core: Core Library for JanusGraph 1.0.1-20240312-113658.3557e4b API)

java.lang.Object
- org.janusgraph.graphdb.idmanagement.IDManager

```
public class IDManager
extends Object
```
Handles the allocation of ids based on the type of element Responsible for the bit-wise pattern of JanusGraph's internal id scheme.

Author:

Matthias Broecheler ([email protected])

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`IDManager.VertexIDType` bit mask- Description (+ indicates defined type, * indicates proper & defined type) 0 - + User created Vertex 000 - * Normal vertices 010 - * Partitioned vertices 100 - * Unmodifiable (e.g.

Field Summary

Fields
Modifier and Type	Field and Description
`static long`	`MAX_PADDING_BITWIDTH` The maximum number of padding bits of any type
`static int`	`PARTITIONED_VERTEX_PARTITION`
`static int`	`SCHEMA_PARTITION` Id of the partition that schema elements are assigned to
`static int`	`TYPE_LEN_RESERVE` Number of bits that need to be reserved from the type ids for storing additional information during serialization
`static long`	`USERVERTEX_PADDING_BITWIDTH` The padding bit width for user vertices

Constructor Summary

Constructors
Constructor and Description

IDManager()

IDManager(long partitionBits)

Constructors
Constructor and Description
`IDManager()`
`IDManager(long partitionBits)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static long`	`addRelationTypePadding(long id)`
`long`	`fromVertexId(long id)` Converts a JanusGraph vertex id to the user provided id as the inverse mapping of `toVertexId(long)`.
`long`	`getCanonicalVertexId(long partitionedVertexId)`
`StaticBuffer`	`getKey(Object vertexId)`
`Object`	`getKeyID(StaticBuffer b)` Parse and get vertex ID from static buffer Historically, JanusGraph only supports long-type ID, so the buffer was assumed to be 8-byte and represent a long value.
`long`	`getPartitionBound()`
`long`	`getPartitionedVertexId(long partitionedVertexId, long otherPartition)`
`long[]`	`getPartitionedVertexRepresentatives(long partitionedVertexId)`
`long`	`getPartitionHashForId(long id)`
`long`	`getPartitionId(long vertexId)`
`long`	`getRelationCountBound()`
`long`	`getRelationID(long count, long partition)`
`static long`	`getSchemaCountBound()`
`static long`	`getSchemaId(IDManager.VertexIDType type, long count)`
`static long`	`getTemporaryRelationID(long count)`
`static long`	`getTemporaryVertexID(IDManager.VertexIDType type, long count)`
`long`	`getVertexCountBound()`
`long`	`getVertexID(long count, long partition, IDManager.VertexIDType vertexType)`
`boolean`	`isCanonicalVertexId(long partitionVertexId)`
`boolean`	`isEdgeLabelId(Object id)`
`boolean`	`isGenericSchemaVertexId(Object id)`
`boolean`	`isPartitionedVertex(Object id)`
`boolean`	`isPropertyKeyId(Object id)`
`boolean`	`isRelationTypeId(Object id)`
`boolean`	`isSchemaVertexId(Object id)`
`static boolean`	`isSystemRelationTypeId(Object id)`
`static boolean`	`isTemporary(long id)`
`boolean`	`isUnmodifiableVertex(Object id)`
`boolean`	`isUserVertexId(Object vertexId)`
`boolean`	`isVertexLabelVertexId(Object id)`
`static long`	`stripEntireRelationTypePadding(long id)`
`static long`	`stripRelationTypePadding(long id)`
`long`	`toVertexId(long id)` Converts a user provided long id into a JanusGraph vertex id.

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

- Field Detail
  - SCHEMA_PARTITION
```
public static final int SCHEMA_PARTITION
```
    Id of the partition that schema elements are assigned to
    
    See Also:
    
    Constant Field Values
  - PARTITIONED_VERTEX_PARTITION
```
public static final int PARTITIONED_VERTEX_PARTITION
```
    See Also:
    
    Constant Field Values
  - TYPE_LEN_RESERVE
```
public static final int TYPE_LEN_RESERVE
```
    Number of bits that need to be reserved from the type ids for storing additional information during serialization
    
    See Also:
    
    Constant Field Values
  - USERVERTEX_PADDING_BITWIDTH
```
public static final long USERVERTEX_PADDING_BITWIDTH
```
    The padding bit width for user vertices
  - MAX_PADDING_BITWIDTH
```
public static final long MAX_PADDING_BITWIDTH
```
    The maximum number of padding bits of any type
- Constructor Detail
  - IDManager
```
public IDManager(long partitionBits)
```
  - IDManager
```
public IDManager()
```
- Method Detail
  - getPartitionBound
```
public long getPartitionBound()
```
  - isUserVertexId
```
public final boolean isUserVertexId(Object vertexId)
```
  - getPartitionId
```
public long getPartitionId(long vertexId)
```
  - getKey
```
public StaticBuffer getKey(Object vertexId)
```
  - getKeyID
```
public Object getKeyID(StaticBuffer b)
```
    Parse and get vertex ID from static buffer Historically, JanusGraph only supports long-type ID, so the buffer was assumed to be 8-byte and represent a long value. To support non long-type ID, we use a convention that if the buffer's length is not 8 bytes, then it's non long-type ID. The first byte is a marker representing the type of the ID. Currently, there is only one possibility: string-type ID. For string-type ID, we use BufferUtil.getStringIdBuffer(String) to encode it. Note that if the marker + length of the ID is equivalent to 8 bytes, then we add a dummy padding byte at the end to make it not equivalent to 8 bytes. NOTE: due to design reason, the encoding scheme of long-type ID here is different from IDHandler. An important difference here is that the first bit of the first byte for a long-type ID is not guaranteed to be zero (as opposed to the case in IDHandler)). Therefore, we cannot rely on the first byte to check if it's long-type or not. Luckily, we can use the "size == 8" trick to know if the buffer stores a long value, because we know the entire buffer represents the ID only. While in IDHandler, only a (non-fixed) portion of the buffer represents the ID, so we use a different trick there.
    
    Parameters:
    
    b -
    
    Returns:
  - getRelationID
```
public long getRelationID(long count,
                          long partition)
```
  - getVertexID
```
public long getVertexID(long count,
                        long partition,
                        IDManager.VertexIDType vertexType)
```
  - getPartitionHashForId
```
public long getPartitionHashForId(long id)
```
  - getCanonicalVertexId
```
public long getCanonicalVertexId(long partitionedVertexId)
```
  - isCanonicalVertexId
```
public boolean isCanonicalVertexId(long partitionVertexId)
```
  - getPartitionedVertexId
```
public long getPartitionedVertexId(long partitionedVertexId,
                                   long otherPartition)
```
  - getPartitionedVertexRepresentatives
```
public long[] getPartitionedVertexRepresentatives(long partitionedVertexId)
```
  - toVertexId
```
public long toVertexId(long id)
```
    Converts a user provided long id into a JanusGraph vertex id. The id must be positive and less than getVertexCountBound(). This method is useful when providing ids during vertex creation via Graph.addVertex(Object...).
    
    Parameters:
    
    id - long id
    
    Returns:
    
    a corresponding JanusGraph vertex id
    
    See Also:
    
    fromVertexId(long)
  - fromVertexId
```
public long fromVertexId(long id)
```
    Converts a JanusGraph vertex id to the user provided id as the inverse mapping of toVertexId(long).
    
    Parameters:
    
    id - JanusGraph vertex id (must be positive)
    
    Returns:
    
    original user provided id
    
    See Also:
    
    toVertexId(long)
  - isPartitionedVertex
```
public boolean isPartitionedVertex(Object id)
```
  - getRelationCountBound
```
public long getRelationCountBound()
```
  - getVertexCountBound
```
public long getVertexCountBound()
```
  - getTemporaryRelationID
```
public static long getTemporaryRelationID(long count)
```
  - getTemporaryVertexID
```
public static long getTemporaryVertexID(IDManager.VertexIDType type,
                                        long count)
```
  - isTemporary
```
public static boolean isTemporary(long id)
```
  - getSchemaId
```
public static long getSchemaId(IDManager.VertexIDType type,
                               long count)
```
  - stripEntireRelationTypePadding
```
public static long stripEntireRelationTypePadding(long id)
```
  - stripRelationTypePadding
```
public static long stripRelationTypePadding(long id)
```
  - addRelationTypePadding
```
public static long addRelationTypePadding(long id)
```
  - isSystemRelationTypeId
```
public static boolean isSystemRelationTypeId(Object id)
```
  - getSchemaCountBound
```
public static long getSchemaCountBound()
```
  - isSchemaVertexId
```
public final boolean isSchemaVertexId(Object id)
```
  - isRelationTypeId
```
public final boolean isRelationTypeId(Object id)
```
  - isEdgeLabelId
```
public final boolean isEdgeLabelId(Object id)
```
  - isPropertyKeyId
```
public final boolean isPropertyKeyId(Object id)
```
  - isGenericSchemaVertexId
```
public boolean isGenericSchemaVertexId(Object id)
```
  - isVertexLabelVertexId
```
public boolean isVertexLabelVertexId(Object id)
```
  - isUnmodifiableVertex
```
public boolean isUnmodifiableVertex(Object id)
```

Class IDManager

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

SCHEMA_PARTITION

PARTITIONED_VERTEX_PARTITION

TYPE_LEN_RESERVE

USERVERTEX_PADDING_BITWIDTH

MAX_PADDING_BITWIDTH

Constructor Detail

IDManager

IDManager

Method Detail

getPartitionBound

isUserVertexId

getPartitionId

getKey

getKeyID

getRelationID

getVertexID

getPartitionHashForId

getCanonicalVertexId

isCanonicalVertexId

getPartitionedVertexId

getPartitionedVertexRepresentatives

toVertexId

fromVertexId

isPartitionedVertex

getRelationCountBound

getVertexCountBound

getTemporaryRelationID

getTemporaryVertexID

isTemporary

getSchemaId

stripEntireRelationTypePadding

stripRelationTypePadding

addRelationTypePadding

isSystemRelationTypeId

getSchemaCountBound

isSchemaVertexId

isRelationTypeId

isEdgeLabelId

isPropertyKeyId

isGenericSchemaVertexId

isVertexLabelVertexId

isUnmodifiableVertex