Add implemented the CSVReader functions

CM2005 Object Oriented Programming/Topic 3/3.4.9/CSVReader.cpp

@@ -0,0 +1,90 @@
+#include "CSVReader.h"
+#include "OrderBookEntry.h"
+#include <fstream>
+#include <iostream>
+
+CSVReader::CSVReader()
+{
+
+}
+
+std::vector<OrderBookEntry> CSVReader::readCSV(std::string csvFilename)
+{
+  std::vector<OrderBookEntry> entries;
+
+  std::string line;
+  std::ifstream csvFile{csvFilename};
+
+  if(csvFile.is_open())
+  {
+    int count = 1;
+    while (std::getline(csvFile, line))
+    {
+      
+      try
+      {
+        OrderBookEntry obe = stringsToBE(tokenise(line, ','));
+        entries.push_back(obe);
+      }
+      catch(const std::exception& e)
+      {
+        // std::cerr << e.what() << '\n';
+        // reached error
+        std::cout << "Error at line " << count << std::endl;
+      }++count;
+    }
+    std::cout << "Read: " <<entries.size() << " entries." << std::endl;
+  }
+
+  return entries;
+}
+
+std::vector<std::string> CSVReader::tokenise(std::string csvLine, char separator)
+{
+  std::vector<std::string> tokens;
+  signed int start{}, end{};
+  std::string token;
+  start = csvLine.find_first_not_of(separator, 0);
+  do
+  {
+    end = csvLine.find_first_of(separator, start);
+    if(start == csvLine.length() || start == end) break;
+    if(end >= 0)
+      token = csvLine.substr(start, end - start);
+    else
+      token = csvLine.substr(start, csvLine.length() - start);
+    
+    tokens.push_back(token);
+    start = end + 1;
+  }
+  while (end > 0);
+  return tokens;
+}
+
+OrderBookEntry CSVReader::stringsToBE(std::vector<std::string> tokens)
+{
+  if(tokens.size() != 5) //bad
+  {
+    throw std::exception{};
+  }
+  
+  // We checked and we have 5 tokens
+  double price{};
+  double amount{};
+  try
+  {
+    price = std::stod(tokens[3]);
+    amount = std::stod(tokens[4]);
+  }
+  catch(const std::exception& e)
+  {
+    throw e;
+  }
+
+  OrderBookEntry obe{ price,
+                      amount,
+                      tokens[0],
+                      tokens[1],
+                      OrderBookEntry::stringToOrderBookType(tokens[2])};
+  return obe;
+}