HashPartitioningFunction (Dataflow Library Distribution Project 8.2.0-176 API)

java.lang.Object
- com.pervasive.datarush.ports.record.HashPartitioningFunction

All Implemented Interfaces:: PartitioningFunction

public final class HashPartitioningFunction
extends Object
implements PartitioningFunction

A default hash partitioning function

Nested Class Summary
- Nested classes/interfaces inherited from interface com.pervasive.datarush.ports.record.PartitioningFunction
  PartitioningFunction.Evaluator

Field Summary

Fields
Modifier and Type Field Description

static HashPartitioningFunction INSTANCE
The single instance of this class

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`PartitioningFunction.Evaluator`	`getEvaluator(PartitioningFunctionContext ctx)`	Create an Evaluator bound to the specified context.
`boolean`	`isEquivalentPartitioning(PartitioningFunction other)`	Returns true iff, given a single row of input, this function is guaranteed to produce the same partitioning as the other function.
`boolean`	`isFunctionOfInput()`	Returns true iff, given two identical rows of input, this function will return the same value.
`PartitioningFunction`	`remapFieldReferences(Map<String,String> oldToNewMapping)`	Creates a new function, equivalent to the given function, but with all field references renamed according to the given mapping.
`void`	`validateForType(RecordTokenType type)`	Performs validation of the specified input type

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

- Field Detail
  - INSTANCE
```
public static HashPartitioningFunction INSTANCE
```
    The single instance of this class
- Method Detail
  - getEvaluator
```
public PartitioningFunction.Evaluator getEvaluator(PartitioningFunctionContext ctx)
```
    Description copied from interface: PartitioningFunction
    
    Create an Evaluator bound to the specified context.
    
    Specified by:
    
    getEvaluator in interface PartitioningFunction
    
    Parameters:
    
    ctx - the partitioning context
    
    Returns:
    
    an Evaluator bound to the specified context.
  - validateForType
```
public void validateForType(RecordTokenType type)
```
    Description copied from interface: PartitioningFunction
    
    Performs validation of the specified input type
    
    Specified by:
    
    validateForType in interface PartitioningFunction
    
    Parameters:
    
    type - the input type
  - isEquivalentPartitioning
```
public boolean isEquivalentPartitioning(PartitioningFunction other)
```
    Description copied from interface: PartitioningFunction
    
    Returns true iff, given a single row of input, this function is guaranteed to produce the same partitioning as the other function. A return of true thus implies the following:
  - both functions are deterministic
  - both function are stateless (not sensitive to previous values read or to input ordering)

Specified by:: isEquivalentPartitioning in interface PartitioningFunction
Parameters:: other - the other function
Returns:: whether this function produces the same results as the other function.

isFunctionOfInput
```
public boolean isFunctionOfInput()
```
Description copied from interface: PartitioningFunction

Returns true iff, given two identical rows of input, this function will return the same value. A return of true thus implies :
the function is deterministic
the function is stateless (not sensitive to previous values read or to input ordering)

Specified by:: isFunctionOfInput in interface PartitioningFunction
Returns:: whether this function is a stateless, deterministic function of input

remapFieldReferences
```
public PartitioningFunction remapFieldReferences(Map<String,String> oldToNewMapping)
```
Description copied from interface: PartitioningFunction

Creates a new function, equivalent to the given function, but with all field references renamed according to the given mapping.

Specified by:

remapFieldReferences in interface PartitioningFunction

Parameters:

oldToNewMapping - a mapping from old names to new names. If a name is not present in the given mapping, it will remain as-is.

Returns:

a new function with all field reference renamed appropriately