Added StockFileHandler class and temporary aksjer.csv file

Added aksjer.csv file for testing purposes, will be deleted later

src/main/java/StockFileHandler.java

@@ -0,0 +1,50 @@
+import java.nio.file.*;
+import java.io.IOException;
+import java.math.BigDecimal;
+import java.util.ArrayList;
+import java.util.List;
+
+public class StockFileHandler {
+
+    // lesing
+    public List<Stock> loadStocksFromFile(String filename) throws IOException {
+        List<Stock> stocks = new ArrayList<>();
+        List<String> lines = Files.readAllLines(Paths.get(filename));
+
+        for (String line : lines) {
+            line = line.trim();
+            if (line.isEmpty() || line.startsWith("#")) {
+                continue;
+            }
+
+            String[] parts = line.split(",");
+            if (parts.length == 3) {
+                String symbol = parts[0];
+                String name = parts[1];
+                BigDecimal price = new BigDecimal(parts[2]);
+
+                stocks.add(new Stock(symbol, name, price));
+            }
+        }
+        return stocks; // returnerer listen 
+    }
+
+    // lagring
+    public void saveStocksToFile(String filename, List<Stock> stocks) throws IOException {
+        List<String> lines = new ArrayList<>();
+
+        // header 
+        lines.add("# Ticker,Name,Price");
+
+        for (Stock stock : stocks) {
+            // formaterer hver aksje som "SYMBOL,NAME,PRICE"
+            String line = String.format("%s,%s,%s", 
+                stock.getSymbol(), 
+                stock.getCompany(), 
+                stock.getSalesPrice().toString());
+            lines.add(line);
+        }
+
+        Files.write(Paths.get(filename), lines);
+    }
+}

src/main/java/aksjer.csv

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+# Top 500 US Stocks by Market Cap
+# Ticker,Name,Price
+NVDA,Nvidia,191.27
+AAPL,Apple Inc.,276.43
+MSFT,Microsoft,404.68