Hash (Jackrabbit Oak 1.78.0 API)

java.lang.Object
- org.apache.jackrabbit.oak.index.indexer.document.flatfile.analysis.utils.Hash

```
public class Hash
extends Object
```
A hash function utility class.

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static long`	`hash64(long x)`	Calculate a 64-bit hash value from a value.
`static long`	`hash64(long x, long seed)`	Calculate a 64-bit hash value from a value, using a seed.
`static int`	`reduce(int hash, int n)`	Shrink the hash to a value 0..n.

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

- Method Detail
  - hash64
```
public static long hash64(long x,
                          long seed)
```
    Calculate a 64-bit hash value from a value, using a seed. The current algorithm used the finalizer of the MurmurHash3 hash function, but callers shouldn't rely on that.
    
    Parameters:
    
    x - the value
    
    seed - the seed
    
    Returns:
    
    the hash value
  - hash64
```
public static long hash64(long x)
```
    Calculate a 64-bit hash value from a value. The input is a 64-bit value and the output is a 64-bit values. Two different inputs are never mapped to the same output. The operation is reversible.
    
    Parameters:
    
    x - the value
    
    Returns:
    
    the hash value
  - reduce
```
public static int reduce(int hash,
                         int n)
```
    Shrink the hash to a value 0..n. Kind of like modulo, but using multiplication and shift, which are faster to compute.
    
    Parameters:
    
    hash - the hash
    
    n - the maximum of the result
    
    Returns:
    
    the reduced value