From http://examples.javacodegeeks.com/core-java/quicksort-algorithm-in-java-code-example/

package com.javacodegeeks.sorting.quicksort;public class QuicksortExample {	private static int []a;	public static void main(String[] args) {		// Get a random generated array		a = getArray();				// prints the given array		printArray();				// sort the array		sort();				System.out.println("");				//prints the sorted array		printArray();			}		// This method sorts an array and internally calls quickSort 	public static void sort(){		int left = 0;		int right = a.length-1;					quickSort(left, right);	}		// This method is used to sort the array using quicksort algorithm.	// It takes the left and the right end of the array as the two cursors.	private static void quickSort(int left,int right){				// If both cursor scanned the complete array quicksort exits		if(left >= right)			return;				// For the simplicity, we took the right most item of the array as a pivot 		int pivot = a[right];		int partition = partition(left, right, pivot);				// Recursively, calls the quicksort with the different left and right parameters of the sub-array		quickSort(0, partition-1);		quickSort(partition+1, right);	}		// This method is used to partition the given array and returns the integer which points to the sorted pivot index	private static int partition(int left,int right,int pivot){		int leftCursor = left-1;		int rightCursor = right;		while(leftCursor < rightCursor){                while(a[++leftCursor] < pivot);                while(rightCursor > 0 && a[--rightCursor] > pivot);			if(leftCursor >= rightCursor){				break;			}else{				swap(leftCursor, rightCursor);			}		}		swap(leftCursor, right);		return leftCursor;	}		// This method is used to swap the values between the two given index	public static void swap(int left,int right){		int temp = a[left];		a[left] = a[right];		a[right] = temp;	}		public static void printArray(){		for(int i : a){			System.out.print(i+" ");		}	}		public static int[] getArray(){		int size=10;		int []array = new int[size];		int item = 0;		for(int i=0;i<size;i++){			item = (int)(Math.random()*100); 			array[i] = item;		}		return array;	}}

Quick Sort