海量数据相似度计算

package nbu.top.recommendation;

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.TimerTask;
import java.util.Map.Entry;

import nbu.top.util.DBHelperRecom;
import nbu.top.util.DBHelperService;

public class main1 extends TimerTask {

// 处理动态数据
int order;
int max;

public void run() {
String url = "jdbc:mysql://ip/test_source?useSSL=false";
String url1 = "jdbc:mysql://ip/test_source?useSSL=false";
DBHelperRecom dbHelper = new DBHelperRecom(url); // 连接数据库recommendation
DBHelperService dbHelper2 = new DBHelperService(url1); // 连接数据库service
String db = "article_integration_lxl";
String db1 = "article_similar";
try {
ArrayList<String> categoryID = new ArrayList<>();
categoryID = dbHelper.getRescyList();
 order = dbHelper2.readorder();