diff --git a/03/src/de/dis2013/data/Haus.java b/03/src/de/dis2013/data/Haus.java
index 40f52ec..c67e36b 100644
--- a/03/src/de/dis2013/data/Haus.java
+++ b/03/src/de/dis2013/data/Haus.java
@@ -52,20 +52,15 @@ public class Haus extends Immobilie {
 			return false;
 	
 		Haus other = (Haus)obj;
-	
-		if(other.getId() != getId() ||
-				other.getPlz() != getPlz() ||
-				other.getFlaeche() != getFlaeche() ||
-				!Helper.compareObjects(this.getOrt(), other.getOrt()) ||
-				!Helper.compareObjects(this.getStrasse(), other.getStrasse()) ||
-				!Helper.compareObjects(this.getHausnummer(), other.getHausnummer()) ||
-				getStockwerke() != other.getStockwerke() ||
-				getKaufpreis() != other.getKaufpreis() ||
-				isGarten() != other.isGarten())
-		{
-			return false;
-		}
 		
-		return true;
+		return !(other.getId() != getId() ||
+		         other.getPlz() != getPlz() ||
+		         other.getFlaeche() != getFlaeche() ||
+		         !Helper.compareObjects(this.getOrt(), other.getOrt()) ||
+		         !Helper.compareObjects(this.getStrasse(), other.getStrasse()) ||
+		         !Helper.compareObjects(this.getHausnummer(), other.getHausnummer()) ||
+		         getStockwerke() != other.getStockwerke() ||
+		         getKaufpreis() != other.getKaufpreis() ||
+		         isGarten() != other.isGarten());
 	}
 }
diff --git a/03/src/de/dis2013/data/Immobilie.java b/03/src/de/dis2013/data/Immobilie.java
index 102c846..134bd62 100644
--- a/03/src/de/dis2013/data/Immobilie.java
+++ b/03/src/de/dis2013/data/Immobilie.java
@@ -13,7 +13,7 @@ public abstract class Immobilie {
 	private String hausnummer;
 	private int flaeche;
 	private Makler verwalter;
-	static int currentId = 0;
+	private static int currentId = 0;
 	
 	public Immobilie() {
 		this.id = currentId++;
@@ -83,17 +83,12 @@ public abstract class Immobilie {
 			return false;
 	
 		Immobilie other = (Immobilie)obj;
-	
-		if(other.getId() != getId() ||
-				other.getPlz() != getPlz() ||
-				other.getFlaeche() != getFlaeche() ||
-				!Helper.compareObjects(this.getOrt(), other.getOrt()) ||
-				!Helper.compareObjects(this.getStrasse(), other.getStrasse()) ||
-				!Helper.compareObjects(this.getHausnummer(), other.getHausnummer()))
-		{
-			return false;
-		}
 		
-		return true;
+		return !(other.getId() != getId() ||
+		         other.getPlz() != getPlz() ||
+		         other.getFlaeche() != getFlaeche() ||
+		         !Helper.compareObjects(this.getOrt(), other.getOrt()) ||
+		         !Helper.compareObjects(this.getStrasse(), other.getStrasse()) ||
+		         !Helper.compareObjects(this.getHausnummer(), other.getHausnummer()));
 	}
 }
diff --git a/03/src/de/dis2013/data/Kaufvertrag.java b/03/src/de/dis2013/data/Kaufvertrag.java
index b953697..ed80451 100644
--- a/03/src/de/dis2013/data/Kaufvertrag.java
+++ b/03/src/de/dis2013/data/Kaufvertrag.java
@@ -53,16 +53,11 @@ public class Kaufvertrag extends Vertrag {
 			return false;
 	
 		Kaufvertrag other = (Kaufvertrag)obj;
-	
-		if(other.getVertragsnummer() != getVertragsnummer() ||
-				!Helper.compareObjects(this.getDatum(), other.getDatum()) ||
-				!Helper.compareObjects(this.getOrt(), other.getOrt()) ||
-				other.getAnzahlRaten() != getAnzahlRaten() ||
-				other.getRatenzins() != getRatenzins())
-		{
-			return false;
-		}
 		
-		return true;
+		return !(other.getVertragsnummer() != getVertragsnummer() ||
+		         !Helper.compareObjects(this.getDatum(), other.getDatum()) ||
+		         !Helper.compareObjects(this.getOrt(), other.getOrt()) ||
+		         other.getAnzahlRaten() != getAnzahlRaten() ||
+		         other.getRatenzins() != getRatenzins());
 	}
 }
diff --git a/03/src/de/dis2013/data/Makler.java b/03/src/de/dis2013/data/Makler.java
index a3c02b5..b9996a8 100644
--- a/03/src/de/dis2013/data/Makler.java
+++ b/03/src/de/dis2013/data/Makler.java
@@ -87,16 +87,11 @@ public class Makler {
 			return false;
 	
 		Makler other = (Makler)obj;
-	
-		if(other.getId() != getId() ||
-				!Helper.compareObjects(getName(), other.getName()) ||
-				!Helper.compareObjects(getAdresse(), other.getAdresse()) ||
-				!Helper.compareObjects(getLogin(), other.getLogin()) ||
-				!Helper.compareObjects(getPasswort(), other.getPasswort()))
-		{
-			return false;
-		}
 		
-		return true;
+		return !(other.getId() != getId() ||
+		         !Helper.compareObjects(getName(), other.getName()) ||
+		         !Helper.compareObjects(getAdresse(), other.getAdresse()) ||
+		         !Helper.compareObjects(getLogin(), other.getLogin()) ||
+		         !Helper.compareObjects(getPasswort(), other.getPasswort()));
 	}
 }
diff --git a/03/src/de/dis2013/data/Mietvertrag.java b/03/src/de/dis2013/data/Mietvertrag.java
index 81d0150..153cf25 100644
--- a/03/src/de/dis2013/data/Mietvertrag.java
+++ b/03/src/de/dis2013/data/Mietvertrag.java
@@ -63,17 +63,12 @@ public class Mietvertrag extends Vertrag {
 			return false;
 	
 		Mietvertrag other = (Mietvertrag)obj;
-	
-		if(other.getVertragsnummer() != getVertragsnummer() ||
-				!Helper.compareObjects(this.getDatum(), other.getDatum()) ||
-				!Helper.compareObjects(this.getOrt(), other.getOrt()) ||
-				other.getDauer() != getDauer() ||
-				other.getNebenkosten() != getNebenkosten() ||
-				!Helper.compareObjects(other.getMietbeginn(), getMietbeginn()))
-		{
-			return false;
-		}
 		
-		return true;
+		return !(other.getVertragsnummer() != getVertragsnummer() ||
+		         !Helper.compareObjects(this.getDatum(), other.getDatum()) ||
+		         !Helper.compareObjects(this.getOrt(), other.getOrt()) ||
+		         other.getDauer() != getDauer() ||
+		         other.getNebenkosten() != getNebenkosten() ||
+		         !Helper.compareObjects(other.getMietbeginn(), getMietbeginn()));
 	}
 }
diff --git a/03/src/de/dis2013/data/Person.java b/03/src/de/dis2013/data/Person.java
index a3cf8e1..a791e16 100644
--- a/03/src/de/dis2013/data/Person.java
+++ b/03/src/de/dis2013/data/Person.java
@@ -58,15 +58,10 @@ public class Person {
 			return false;
 	
 		Person other = (Person)obj;
-	
-		if(other.getId() != getId() ||
-				!Helper.compareObjects(this.getVorname(), other.getVorname()) ||
-				!Helper.compareObjects(this.getNachname(), other.getNachname()) ||
-				!Helper.compareObjects(this.getAdresse(), other.getAdresse()))
-		{
-			return false;
-		}
 		
-		return true;
+		return !(other.getId() != getId() ||
+		         !Helper.compareObjects(this.getVorname(), other.getVorname()) ||
+		         !Helper.compareObjects(this.getNachname(), other.getNachname()) ||
+		         !Helper.compareObjects(this.getAdresse(), other.getAdresse()));
 	}
 }
diff --git a/03/src/de/dis2013/data/Vertrag.java b/03/src/de/dis2013/data/Vertrag.java
index 9dfebb2..34d4de0 100644
--- a/03/src/de/dis2013/data/Vertrag.java
+++ b/03/src/de/dis2013/data/Vertrag.java
@@ -11,9 +11,9 @@ public abstract class Vertrag {
 	private int vertragsnummer = -1;
 	private Date datum;
 	private String ort;
-	static int currentId = 0;
-	int id;
-	Person vertragspartner;
+	private static int currentId = 0;
+	private int    id;
+	private Person vertragspartner;
 	
 	public Vertrag() {
 		this.id = currentId++;
@@ -72,14 +72,9 @@ public abstract class Vertrag {
 			return false;
 	
 		Vertrag other = (Vertrag)obj;
-	
-		if(other.getVertragsnummer() != getVertragsnummer() ||
-				!Helper.compareObjects(this.getDatum(), other.getDatum()) ||
-				!Helper.compareObjects(this.getOrt(), other.getOrt()))
-		{
-			return false;
-		}
 		
-		return true;
+		return !(other.getVertragsnummer() != getVertragsnummer() ||
+		         !Helper.compareObjects(this.getDatum(), other.getDatum()) ||
+		         !Helper.compareObjects(this.getOrt(), other.getOrt()));
 	}
 }
diff --git a/03/src/de/dis2013/data/Wohnung.java b/03/src/de/dis2013/data/Wohnung.java
index f40167c..4ffd7e9 100644
--- a/03/src/de/dis2013/data/Wohnung.java
+++ b/03/src/de/dis2013/data/Wohnung.java
@@ -69,22 +69,17 @@ public class Wohnung extends Immobilie {
 			return false;
 	
 		Wohnung other = (Wohnung)obj;
-	
-		if(other.getId() != getId() ||
-				other.getPlz() != getPlz() ||
-				other.getFlaeche() != getFlaeche() ||
-				!Helper.compareObjects(this.getOrt(), other.getOrt()) ||
-				!Helper.compareObjects(this.getStrasse(), other.getStrasse()) ||
-				!Helper.compareObjects(this.getHausnummer(), other.getHausnummer()) ||
-				getStockwerk() != other.getStockwerk() ||
-				getMietpreis() != other.getMietpreis() ||
-				getZimmer() != other.getZimmer() ||
-				isBalkon() != other.isBalkon() ||
-				isEbk() != other.isEbk())
-		{
-			return false;
-		}
 		
-		return true;
+		return !(other.getId() != getId() ||
+		         other.getPlz() != getPlz() ||
+		         other.getFlaeche() != getFlaeche() ||
+		         !Helper.compareObjects(this.getOrt(), other.getOrt()) ||
+		         !Helper.compareObjects(this.getStrasse(), other.getStrasse()) ||
+		         !Helper.compareObjects(this.getHausnummer(), other.getHausnummer()) ||
+		         getStockwerk() != other.getStockwerk() ||
+		         getMietpreis() != other.getMietpreis() ||
+		         getZimmer() != other.getZimmer() ||
+		         isBalkon() != other.isBalkon() ||
+		         isEbk() != other.isEbk());
 	}
 }