BlankNodeAllocatorHash (Apache Jena ARQ)

java.lang.Object
- org.apache.jena.riot.lang.BlankNodeAllocatorHash

All Implemented Interfaces:

BlankNodeAllocator

Direct Known Subclasses:

BlankNodeAllocatorFixedSeedHash
```
public class BlankNodeAllocatorHash
extends java.lang.Object
implements BlankNodeAllocator
```
Allocate bnode labels using a per-run seed and the label presented.
This is the most scalable, always legal allocator.
New allocators must be created per parser run, or .reset() called. These are fed to a digest to give a bit string, (currently MD5, to get a 128bit bit string) that is used to form a bNode AnonId of hex digits.
In addition, there is a cache of label->node allocations, using the natural tendency to locality in a database dump. (subject bNodes, bNodes in lists and other data values structures like unit values).
Not thread safe.

Constructor Summary

Constructors
Constructor Description

BlankNodeAllocatorHash()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`Node`	`alloc(java.lang.String label)`	Allocate based on a non-null label.
`Node`	`create()`	Create a fresh blank node, different from anything generated so far.
`void`	`reset()`	Reset allocation state - calls to `BlankNodeAllocator.alloc(java.lang.String)` or `BlankNodeAllocator.create()`

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

- Constructor Detail
  - BlankNodeAllocatorHash
```
public BlankNodeAllocatorHash()
```
- Method Detail
  - reset
```
public void reset()
```
    Description copied from interface: BlankNodeAllocator
    
    Reset allocation state - calls to BlankNodeAllocator.alloc(java.lang.String) or BlankNodeAllocator.create()
    
    Specified by:
    
    reset in interface BlankNodeAllocator
  - alloc
```
public Node alloc(java.lang.String label)
```
    Description copied from interface: BlankNodeAllocator
    
    Allocate based on a non-null label. Calling this twice, with the same label will generate equivalent nodes but they may not be identical (i.e they are .equals but may not be ==)
    
    Specified by:
    
    alloc in interface BlankNodeAllocator
  - create
```
public Node create()
```
    Description copied from interface: BlankNodeAllocator
    
    Create a fresh blank node, different from anything generated so far. Will not clash with a node allocated by BlankNodeAllocator.alloc(java.lang.String)
    
    Specified by:
    
    create in interface BlankNodeAllocator