update,

it114105/itp3914/Lab10/Ex4/CurrencyConverter.java

@@ -0,0 +1,48 @@
+class CurrencyConverter {
+	private double exchangeRate;
+	private double commissionRate;
+	private int largeAmount;
+ 
+	public CurrencyConverter(double er , double cr){
+		exchangeRate = er;
+		commissionRate = cr;
+	}
+ 
+	public double fromUSDollar(double dollar){
+		if (dollar >= largeAmount)
+			return (dollar * exchangeRate * (1-commissionRate*0.5));
+		else
+			return (dollar * exchangeRate * (1-commissionRate));
+	}
+ 
+	public double toUSDollar(double foreignMoney){
+		if (foreignMoney/exchangeRate >= largeAmount)
+			return (foreignMoney/exchangeRate*(1-commissionRate*0.5));
+		else
+			return (foreignMoney/exchangeRate*(1-commissionRate));
+	}
+ 
+	public void setExchangeRate(double rate){
+		exchangeRate = rate;
+	}
+ 
+	public double getExchangeRate(){
+		return exchangeRate;
+	}
+ 
+	public void setCommissionRate(double rate){
+		commissionRate = rate;
+	}
+ 
+	public double getCommissionRate(){
+		return commissionRate;
+	}
+ 
+	public void setLargeAmount(int amount){
+		largeAmount = amount;
+	}
+ 
+	public int getLargeAmount(){
+		return largeAmount;
+	}
+}

it114105/itp3914/Lab10/Ex4/Ex4.java

@@ -0,0 +1,19 @@
+public class Ex4 {
+    public static void main(String[] args) {
+        CurrencyConverter yenConverter = new CurrencyConverter(115.7, 0.0005);
+        CurrencyConverter euroConverter = new CurrencyConverter(0.9881, 0.0003);
+        
+        yenConverter.setLargeAmount(50000);
+        euroConverter.setLargeAmount(50000);
+        int yens = 1500000;
+        System.out.println(yens + " yens = US$ " + yenConverter.toUSDollar(yens));
+        int usd = 20000;
+        System.out.println("US$ " + usd + " = " + yenConverter.fromUSDollar(usd) + " yens");
+
+        int euros = 170000;
+        System.out.println(euros + " euros = US$ " + euroConverter.toUSDollar(euros));
+        usd = 20000;
+        System.out.println("US$ " + usd + " = " + euroConverter.fromUSDollar(usd) + " euros");
+
+    }
+}