package com.fasterxml.sort;
import com.fasterxml.sort.std.StdTempFileProvider;
/**
* Configuration object used for changing details of sorting
* process. Default settings are usable, so often
* instance is created without arguments and used as is.
*/
public class SortConfig
{
/**
* By default we will use 40 megs for pre-sorting.
*/
public final static long DEFAULT_MEMORY_USAGE = 40 * 1024 * 1024;
/**
* Default merge sort is 16-way sort (using 16 input files concurrently)
*/
public final static int DEFAULT_MERGE_FACTOR = 16;
protected int _mergeFactor;
protected long _maxMemoryUsage;
protected TempFileProvider _tempFileProvider;
/*
/************************************************************************
/* Construction
/************************************************************************
*/
public SortConfig()
{
_mergeFactor = DEFAULT_MERGE_FACTOR;
_maxMemoryUsage = DEFAULT_MEMORY_USAGE;
_tempFileProvider = new StdTempFileProvider();
}
protected SortConfig(SortConfig base, int mergeFactor) {
_maxMemoryUsage = base._maxMemoryUsage;
_mergeFactor = mergeFactor;
_tempFileProvider = base._tempFileProvider;
}
protected SortConfig(SortConfig base, long maxMem) {
_maxMemoryUsage = maxMem;
_mergeFactor = base._mergeFactor;
_tempFileProvider = base._tempFileProvider;
}
protected SortConfig(SortConfig base, TempFileProvider prov) {
_mergeFactor = base._mergeFactor;
_maxMemoryUsage = base._maxMemoryUsage;
_tempFileProvider = prov;
}
/*
/************************************************************************
/* Accessors
/************************************************************************
*/
public int getMergeFactor() { return _mergeFactor; }
public long getMaxMemoryUsage() { return _maxMemoryUsage; }
public TempFileProvider getTempFileProvider() { return _tempFileProvider; }
/*
/************************************************************************
/* Fluent construction methods
/************************************************************************
*/
/**
* Method for constructing configuration instance that defines that maximum amount
* of memory to use for pre-sorting. This is generally a crude approximation and
* implementations make best effort to honor it.
*
* @param maxMem Maximum memory that pre-sorted should use for in-memory sorting
* @return New
*/
public SortConfig withMaxMemoryUsage(long maxMem)
{
if (maxMem == _maxMemoryUsage) {
return this;
}
return new SortConfig(this, maxMem);
}
public SortConfig withTempFileProvider(TempFileProvider provider)
{
if (provider == _tempFileProvider) {
return this;
}
return new SortConfig(this, provider);
}
}