random

import java.util.Random;
import java.util.ArrayList;

prevTreshold = vars.get("TRESHOLD");
prevSwitchId = vars.get("SWITCH_ID");
numItems = Integer.parseInt(vars.get("NUM_ITEMS"));

Random rand = new Random();
item = 1 + rand.nextInt(numItems);
vars.put("ITEM_ID", Integer.toString(item));

treshold = 1+rand.nextInt(numItems);
vars.put("TRESHOLD", Integer.toString(treshold));

//System.out.println("Treshold1 = " + treshold);
//System.out.println("ITEM_ID1 = " + item);

[BeanShell PreProcessor] ITEM_ID

int ADMIN_CONFIRM = 0;
int ADMIN_REQUEST = 1;
int BEST_SELLERS = 2;
int BUY_CONFIRM = 3;
int BUY_REQUEST = 4;
int CUSTOMER_REGISTRATION = 5;
int HOME = 6;
int NEW_PRODUCTS = 7;
int ORDER_DISPLAY = 8;
int ORDER_INQUIRY = 9;
int PRODUCT_DETAIL = 10;
int SEARCH_REQUEST = 11;
int SEARCH_RESULTS = 12;
int SHOPPING_CART = 13;

/*
 * See http://www.tpc.org/tpcw/spec/tpcw_v16.pdf page 94
 */
int[][] tresholdsMatrix = {
    {0, 0, 0, 0, 0, 0, 9952, 0, 0, 0, 0, 9999, 0, 0},
    {8999, 0, 0, 0, 0, 0, 9999, 0, 0, 0, 0, 0, 0, 0},
    {0,0,0,0,0, 0, 167, 0,0,0, 472, 9927,0,9999},
    {0,0,0,0,0, 0, 84, 0,0,0,0,9999,0,0},
    {0,0,0,4614,0, 0, 6546, 0,0,0,0,0,0,9999},
    {0,0,0,0,8666, 0, 8760, 0,0,0,0,9999,0,0},
    {0,0,3124,0,0, 0, 0, 6249,0, 6718,0,7026,0,9999},
    {0,0,0,0,0, 0, 156, 0,0,0,9735,9784,0,9999},
    {0,0,0,0,0, 0, 69, 0,0,0,0,9999,0,0},
    {0,0,0,0,0, 0, 72, 0,8872,0,0,9999,0,0},
    {0,58,0,0,0, 0, 832, 0,0,0,1288,8603,0,9999},
    {0,0,0,0,0, 0, 635, 0,0,0,0,0,9135,9999},
    {0,0,0,0,0, 0, 2657, 0,0,0,9294,9304,0,9999},
    {0,0,0,0,0, 2585, 9552, 0,0,0,0,0,0,9999},
};

int nextOperation(int currentOperation)
{
    int newOperation = -1;
    
    Random rand = new Random();
    int r = 1 + rand.nextInt(9999);
    
    for( int i = 0; i < tresholdsMatrix[currentOperation].length; i++)
    {
        int t = tresholdsMatrix[currentOperation][i];
        if( r <= t)
            return i;
    }
    
    return newOperation;
}

previousOperation = vars.get("OPERATION");
newOp = nextOperation(Integer.parseInt(previousOperation));
vars.put("OPERATION", String.valueOf(newOp));

import org.apache.commons.math3.distribution.EnumeratedDistribution;
import org.apache.commons.math3.util.Pair;
import java.util.ArrayList;

class Item
{
    String operation;
    double probability;
    int jmeterIndex;
    
    public Item(String operation, double probability, int jmeterIndex)
    {
        this.operation = operation;
        this.probability = probability;
        this.jmeterIndex = jmeterIndex;
    }
}

ArrayList items = new ArrayList(){{
    add(new Item("Home", 29, 7)); 
    add(new Item("New products", 11, 8)); 
    add(new Item("Best Sellers", 11, 3));
    add(new Item("Product Detail", 21, 11)); 
    add(new Item("Search Request", 12, 12));
    add(new Item("Search Results", 11, 13)); 
    add(new Item("Shopping Cart", 1.25, 14));
    add(new Item("Customer Registration", 0.82, 6));
    add(new Item("Buy Request", 0.75, 5));
    add(new Item("Buy Confirm", 0.69, 4));
    add(new Item("Order Inquiry", 0.30, 10));
    add(new Item("Order Display", 0.25, 9));
    add(new Item("Admin Request", 0.10, 2));
    add(new Item("Admin Confirm", 0.09, 1));
}};

ArrayList itemWeights = new ArrayList();
for(Item i : items)
{
    itemWeights.add(new Pair(i, i.probability));
}

newOperation = new EnumeratedDistribution(itemWeights).sample();

vars.put("SWITCH_ID", String.valueOf(newOperation.jmeterIndex));