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package edu.brown.cs.student.term.hub;
import edu.brown.cs.student.term.DatabaseQuerier;
import edu.brown.cs.student.term.trade.Trade;
import java.sql.SQLException;
import java.time.Instant;
import java.util.*;
public class LinkMapper {
//TODO: Review what we actually need in here
//not strictly necessary but may be nice to maintain
//private List<List<Trade>> allTrades = new ArrayList<>();
private Map<Holder, Set<Holder>> followerToLeaders = new HashMap<>();
private static Map<Integer, Set<Trade>> holderIDToTrades = new HashMap<>();
private DatabaseQuerier databaseQuerier;
public LinkMapper(DatabaseQuerier db){
this.databaseQuerier = db;
}
/**
* Returns the follower to leaders map as is, does not update it
* @return person to follower map
*/
public Map<Holder, Set<Holder>> getFollowerToLeaders() {
return followerToLeaders;
}
/**
* This links a person and the set of people whose trades they followed
* in the same time period
* @param start - instant representing start of time period to look at
* @param end - instant representing end of time period to look at
* @return - the newly updated link map
*/
public Map<Holder, Set<Holder>> makeFollowerLinks(Instant start, Instant end){
if(databaseQuerier != null){
try{
List<List<Trade>> allTrades = databaseQuerier.getAllTradesByStock(start, end);
//reset the map to be blank
followerToLeaders = new HashMap<>();
for(List<Trade> tradeList : allTrades){
convertTradeListToFollowerMap(tradeList);
}
} catch(SQLException e) {
System.out.println("ERROR: SQL Error while retrieving trade list");
}
} else {
System.out.println("ERROR: No database loaded in yet");
}
return followerToLeaders;
}
public static List<String> getCommonTrades(int leaderID, int followerID){
Set<Trade> leaderTrades = new HashSet<>(holderIDToTrades.get(leaderID));
Set<Trade> followerTrades = new HashSet<>(holderIDToTrades.get(followerID));
leaderTrades.retainAll(followerTrades);
//TODO: Could retain WAY more info in here!
List<String> commonTrades = new ArrayList<>();
for(Trade leaderTrade: leaderTrades){
String buyType = "";
if(leaderTrade.isBuy()){
buyType = "Buy";
} else{
buyType = "Sell";
}
commonTrades.add(buyType + ": " + leaderTrade.getStock());
}
return commonTrades;
}
/**
* Converts a single trade list into entries in the follower to leader map
* @param tradeList - a list of trades for a single stock (either buy or sell)
*/
private void convertTradeListToFollowerMap(List<Trade> tradeList){
List<Holder> holderList = new ArrayList<>();
//gets in order list of people
for (Trade trade : tradeList) {
Holder currentHolder = trade.getHolder();
holderList.add(currentHolder);
if(!holderIDToTrades.containsKey(currentHolder.getId())){
Set<Trade> tradeSet = new HashSet<>();
tradeSet.add(trade);
holderIDToTrades.put(currentHolder.getId(), tradeSet);
} else {
holderIDToTrades.get(currentHolder.getId()).add(trade);
}
}
//Set<Holder> followers = new HashSet<>(holderList);
Set<Holder> encountered = new HashSet<>();
//[bob, george, jane, bob, mary]
for(Holder current: holderList){
//only want to use first instance of a holder to dictate who they followed
//for instance, if the person whose at the front buys again, they probably
//didn't follow the people in between, just wanted to buy again
if(!encountered.contains(current)){
if(followerToLeaders.containsKey(current)){
//TODO: this probably makes it O(n^2), might want to optimize later
followerToLeaders.get(current).addAll(encountered);
} else {
Set<Holder> currentLeaders = new HashSet<>(encountered);
followerToLeaders.put(current, currentLeaders);
}
encountered.add(current);
}
}
}
//This code creates a leader => follower map!
/*private void convertTradeListToFollowerMap(List<Trade> tradeList){
List<Holder> holderList = new ArrayList<>();
//gets in order list of people
for (Trade trade : tradeList) {
holderList.add(trade.getHolder());
}
Set<Holder> followers = new HashSet<>(holderList);
Set<Holder> encountered = new HashSet<>();
for(Holder current: holderList){
//want to check if we've already gotten followers for this trade for this holder
if(!encountered.contains(current)){
encountered.add(current);
followers.remove(current);
if(personToFollowers.containsKey(current)){
//TODO: this probably makes it O(n^2), might want to optimize later
personToFollowers.get(current).addAll(followers);
} else {
Set<Holder> currentFollowers = new HashSet<>(followers);
personToFollowers.put(current, currentFollowers);
}
}
}
}*/
//Old version using lists of followers, allowing for duplicates
/*private void convertTradeListToFollowerMap(List<Trade> tradeList){
List<Holder> holderList = new ArrayList<>();
//gets in order list of people
for (Trade trade : tradeList) {
holderList.add(trade.getHolder());
}
Set<Holder> followers = new HashSet<>(holderList);
Set<Holder> encountered = new HashSet<>();
for(Holder current: holderList){
//want to check if we've already gotten followers for this trade for this holder
if(!encountered.contains(current)){
encountered.add(current);
followers.remove(current);
if(personToFollowers.containsKey(current)){
//TODO: this probably makes it O(n^2), might want to optimize later
personToFollowers.get(current).addAll(followers);
} else {
List<Holder> currentFollowers = new ArrayList<>(followers);
personToFollowers.put(current, currentFollowers);
}
}
}
}*/
}
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