1 files changed, 99 insertions, 75 deletions
diff --git a/src/de/fhswf/in/inf/java1/aufgabe5/Konto.java b/src/de/fhswf/in/inf/java1/aufgabe5/Konto.java
index 3d3aed5..24194b3 100644
--- a/src/de/fhswf/in/inf/java1/aufgabe5/Konto.java
+++ b/src/de/fhswf/in/inf/java1/aufgabe5/Konto.java
@@ -1,75 +1,99 @@
-/**
- * 
- */
-package de.fhswf.in.inf.java1.aufgabe5;
-
-import java.math.BigDecimal;
-
-/**
- * TODO Add comment here
- *
- * @author $Author: $
- * @version $Revision: $, $Date: $ UTC
- */
-public class Konto
-{
-
-   private BigDecimal guthaben;
-
-   private BigDecimal dispo;
-
-   private Person besitzer;
-
-   /**
-    * TODO Add constructor comment here
-    *
-    * @param besitzer
-    *           Owner of the account
-    * @param dispo
-    *           Dispo of the account
-    * @param guthaben
-    *           Initial balance of the account
-    */
-   public Konto(Person besitzer, BigDecimal dispo, BigDecimal guthaben)
-   {
-
-      if (besitzer == null)
-      {
-         throw new IllegalArgumentException("Besitzer can't be null");
-      }
-      if (dispo == null)
-      {
-         throw new IllegalArgumentException("Dispo can't be null");
-      }
-      if (guthaben == null)
-      {
-         throw new IllegalArgumentException("Guthaben can't be null");
-      }
-
-      this.besitzer = besitzer;
-      this.dispo = dispo;
-      this.guthaben = guthaben;
-
-   }
-
-   /**
-    * TODO Add method comment here
-    *
-    * @param betrag
-    */
-   public void abheben(BigDecimal betrag)
-   {
-
-   }
-
-   /**
-    * TODO Add method comment here
-    *
-    * @param betrag
-    */
-   public void einzahlen(BigDecimal betrag)
-   {
-
-   }
-
-}
+/**
+ * 
+ */
+package de.fhswf.in.inf.java1.aufgabe5;
+
+import java.math.BigDecimal;
+
+/**
+ * An implementation of the Konto class wich represents a bank account.
+ *
+ * @author $Author: $
+ * @version $Revision: $, $Date: $ UTC
+ */
+public class Konto
+{
+
+   private BigDecimal guthaben;
+
+   private BigDecimal dispo;
+
+   private Person besitzer;
+
+   /**
+    * Creates an account with an owner, a dispo and an initial balance.
+    *
+    * @param besitzer
+    *           Owner of the account
+    * @param dispo
+    *           Dispo of the account
+    * @param guthaben
+    *           Initial balance of the account
+    */
+   public Konto(Person besitzer, BigDecimal dispo, BigDecimal guthaben)
+   {
+
+      if (besitzer == null)
+      {
+         throw new IllegalArgumentException("Besitzer can't be null");
+      }
+      if (dispo == null)
+      {
+         throw new IllegalArgumentException("Dispo can't be null");
+      }
+      if (guthaben == null)
+      {
+         throw new IllegalArgumentException("Guthaben can't be null");
+      }
+
+      this.besitzer = besitzer;
+      this.dispo = dispo;
+      this.guthaben = guthaben;
+
+   }
+
+   /**
+    * Function for withdrawing money from the account.
+    *
+    * @param betrag
+    *           Amount of cash to be withdrawn
+    */
+   public void abheben(BigDecimal betrag)
+   {
+      if (betrag == null)
+      {
+         throw new IllegalArgumentException("Betrag can't be null");
+      }
+      if (betrag.compareTo(BigDecimal.ZERO) < 0)
+      {
+         throw new IllegalArgumentException("Betrag can't be negative");
+      }
+      if (guthaben.add(dispo).compareTo(betrag) >= 0)
+      {
+         throw new IllegalArgumentException("Betrag surpasses dispo limit");
+      }
+
+      guthaben = guthaben.subtract(betrag);
+   }
+
+   /**
+    * Function to deposit money into the account.
+    *
+    * @param betrag
+    *           Amount of cash to be disposed
+    */
+   public void einzahlen(BigDecimal betrag)
+   {
+      if (betrag == null)
+      {
+         throw new IllegalArgumentException("Betrag can't be null");
+      }
+      if (betrag.compareTo(BigDecimal.ZERO) < 0)
+      {
+         throw new IllegalArgumentException("Betrag can't be negative");
+      }
+
+      guthaben = guthaben.add(betrag);
+   }
+
+}