漏斗分析算法实现

import lombok.Data;

import java.text.SimpleDateFormat;
import java.util.*;
import java.util.stream.Collectors;

@Data
public class CalculatorDemo {

public static List<FunnelDataDTO> visitList = new ArrayList<FunnelDataDTO>();

static {

    visitList.add(new FunnelDataDTO("ggr", 1535624314001L, "20180830", "v2"));
    visitList.add(new FunnelDataDTO("ggr", 1535624314002L, "20180830", "v1"));
    visitList.add(new FunnelDataDTO("ggr", 1535624314003L, "20180830", "v1"));
    visitList.add(new FunnelDataDTO("ggr", 1535624314004L, "20180830", "v2"));
    visitList.add(new FunnelDataDTO("ggr", 1535624314005L, "20180830", "v1"));

    visitList.add(new FunnelDataDTO("ggr", 1535710714000L, "20180831", "v1"));
    visitList.add(new FunnelDataDTO("ggr", 1535710714001L, "20180831", "v2"));
    visitList.add(new FunnelDataDTO("ggr", 1535710714002L, "20180831", "v1"));
    visitList.add(new FunnelDataDTO("ggr", 1535710714003L, "20180831", "v2"));
    visitList.add(new FunnelDataDTO("ggr", 1535710714004L, "20180831", "v2"));
    visitList.add(new FunnelDataDTO("ggr", 1535710714005L, "20180831", "v2"));

    visitList.add(new FunnelDataDTO("ggr", 1535797114000L, "20180901", "v1"));
    visitList.add(new FunnelDataDTO("ggr", 1535797114003L, "20180901", "v3"));
    visitList.add(new FunnelDataDTO("ggr", 1535797114003L, "20180901", "v2"));
    visitList.add(new FunnelDataDTO("ggr", 1535797114004L, "20180901", "v1"));
    visitList.add(new FunnelDataDTO("ggr", 1535797114004L, "20180901", "v3"));
}


public Map<String,List<Integer>> getDayTransForm(List<FunnelDataDTO> visitList, long startTime, long endTime, int cycle, String step){

    int countDay = Math.ceil((endTime - startTime) / 86400000.0D) > 1.0D ? (int) Math.ceil((endTime - startTime) / 86400000.0D) : 1;
    Map<String, Integer> dayMap = new LinkedHashMap<>(countDay + 1);
    SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd");
    String[] stepArray = step.split(",");
    int[] stepCountArray = new int[stepArray.length];
    while (countDay > 0) {
        /***初始化日期列表和结果列表*/
        dayMap.put(format.format(new java.util.Date(endTime - (86400000 * countDay))), 0);
        countDay--;
    }
    dayMap.put(format.format(new Date(endTime)), 0);
    /**开始查找*/
    for (int k = 0; k < visitList.size(); k++) {
        boolean hasFirstStep = visitList.get(k).getVid().equals(stepArray[0]) && dayMap.get(visitList.get(k).getDay()).equals(0);
        if (hasFirstStep) {
            stepCountArray[0] = 1;
            /*计算左右两边的边界时间,并截取合法的访问记录进行比对*/
            long left = visitList.get(k).getTimestamp().longValue();
            long right = visitList.get(k).getTimestamp().longValue() + (86400000 * cycle);
            List<FunnelDataDTO> subList = visitList.subList(k, visitList.size()).stream()
                    .filter(funnelDataDTO -> funnelDataDTO.getTimestamp() > left && funnelDataDTO.getTimestamp() <= right)
                    .sorted((x, y) -> (int) (y.getTimestamp() - x.getTimestamp()))
                    .collect(Collectors.toList());

            /**记录已经找到的步骤数，只有当所有步骤全部都找到了才算转化成功*/
            int stepCount = stepArray.length - 1;
            for (int l = 0; l < subList.size(); l++) {
                if (subList.get(l).getVid().equals(stepArray[stepCount])) {
                    stepCount--;
                } else {
                    continue;
                }
                /**如果已经找到了所有的步骤就更新一下endStepCount数组，并退出本次循环*/
                if (stepCount == 0) {
                    dayMap.put(visitList.get(k).getDay(), 1);
                    break;
                }
            }

            /**计算每一步的到达人数,得到漏斗图数据*/
            stepCount = 1;
            for (int m = subList.size() - 1; m >= 0; m--) {
                if (stepCount < stepArray.length && subList.get(m).getVid().equals(stepArray[stepCount])) {
                    stepCountArray[stepCount] = 1;
                    stepCount++;
                }
            }
        }
    }

    ArrayList<Integer> trendCountList = new ArrayList<>(dayMap.values());
    List<int[]> stepCountList = Arrays.asList(stepCountArray);
    Map map = new HashMap(2);
    map.put("trendCountList",trendCountList);
    map.put("stepCountList",stepCountList);
    return map;
}


public static void main(String[] args) throws Exception {
    CalculatorDemo demo = new CalculatorDemo();
    Map<String, List<Integer>> dayTransForm = demo.getDayTransForm(CalculatorDemo.visitList, 1535550316000L, 1535809516000L, 2, "v1,v2,v3");
    System.out.println(dayTransForm);

}

}