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## org.apache.lucene.util
Class SorterTemplate

    java.lang.Object
      org.apache.lucene.util.SorterTemplate

    public abstract class SorterTemplate

extends Object

This class was inspired by CGLIB, but provides a better QuickSort algorithm without additional InsertionSort at the end. To use, subclass and override the four abstract methods which compare and modify your data. Allows custom swap so that two arrays can be sorted at the same time.

NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.

Constructor Summary
`SorterTemplate()`

Method Summary
`protected abstract int` | `compare(int i, int j)` Compares slots `i` and `j` of you data.
`protected abstract int` | `comparePivot(int j)` Implements the compare function for the previously stored pivot value.
`void` | `insertionSort(int lo, int hi)` Sorts via stable in-place InsertionSort algorithm (ideal for small collections which are mostly presorted).
`void` | `mergeSort(int lo, int hi)` Sorts via stable in-place MergeSort algorithm For small collections falls back to `insertionSort(int,int)`.
`void` | `quickSort(int lo, int hi)` Sorts via in-place, but unstable, QuickSort algorithm.
`protected abstract void` | `setPivot(int i)` Implement this method, that stores the value of slot `i` as pivot value
`protected abstract void` | `swap(int i, int j)` Implement this method, that swaps slots `i` and `j` in your data

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

Constructor Detail

### SorterTemplate

    public SorterTemplate()

Method Detail

### swap

    protected abstract void swap(int i,
                                 int j)

  Implement this method, that swaps slots `i` and `j` in your data

### compare

    protected abstract int compare(int i,
                                   int j)

  Compares slots `i` and `j` of you data. Should be implemented like `valueOf(i).compareTo(valueOf(j))`

### setPivot

    protected abstract void setPivot(int i)

  Implement this method, that stores the value of slot `i` as pivot value

### comparePivot

    protected abstract int comparePivot(int j)

  Implements the compare function for the previously stored pivot value. Should be implemented like `pivot.compareTo(valueOf(j))`

### insertionSort

    public final void insertionSort(int lo,
                                    int hi)

  Sorts via stable in-place InsertionSort algorithm (ideal for small collections which are mostly presorted).

### quickSort

    public final void quickSort(int lo,
                                int hi)

  Sorts via in-place, but unstable, QuickSort algorithm. For small collections falls back to `insertionSort(int,int)`.

### mergeSort

    public final void mergeSort(int lo,
                                int hi)

  Sorts via stable in-place MergeSort algorithm For small collections falls back to `insertionSort(int,int)`.

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