diff -r 03c5c5dc94e7 -r 58ec6da75f6f task4/solution14/src/org/apidesign/apifest08/currency/Rate.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/task4/solution14/src/org/apidesign/apifest08/currency/Rate.java	Sat Oct 11 23:38:46 2008 +0200
@@ -0,0 +1,68 @@
+
+package org.apidesign.apifest08.currency;
+
+public final class Rate {
+
+    private double rate;
+
+    public Rate(int amountA, int amountB) {
+        rate = amountA / (double)amountB;
+        if (rate <= 0) {
+            throw new IllegalArgumentException("Exchange rate must be positive.");
+        }
+    }
+
+    public Rate(double amountA, double amountB) {
+        rate = amountA / amountB;
+        if (rate <= 0) {
+            throw new IllegalArgumentException("Exchange rate must be positive.");
+        }
+    }
+    
+    public Rate(double rate) {
+        this.rate = rate;
+        if (this.rate <= 0) {
+            throw new IllegalArgumentException("Exchange rate must be positive.");
+        }
+    }
+
+    public double convertAtoB(int a) {
+        return a / rate;
+    }
+
+    public double convertAtoB(double a) {
+        return a / rate;
+    }
+
+    public double convertBtoA(int b) {
+        return b * rate;
+    }
+
+    public double convertBtoA(double b) {
+        return b * rate;
+    }
+
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == null) {
+            return false;
+        }
+        if (getClass() != obj.getClass()) {
+            return false;
+        }
+        final Rate other = (Rate) obj;
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        int hash = 5;
+        return hash;
+    }
+
+    @Override
+    public String toString() {
+        return ""+rate;
+    }
+}