--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/main/java/de/mpiwg/indexmeta/utils/QuadKey.java	Thu Apr 11 15:25:26 2013 +0200
@@ -0,0 +1,116 @@
+package de.mpiwg.indexmeta.utils;
+
+public class QuadKey<F, S, T> {
+	private F firstKey;
+	private S secondKey;
+	private T thirdKey;
+	private Object ownKey;
+	/*
+	public QuadKey(Long firstKey, Long secondKey, Long thirdKey, Long ownKey){
+		this.firstKey = firstKey;
+		this.secondKey = secondKey;
+		this.thirdKey = thirdKey;
+		this.ownKey = ownKey;
+	}*/
+	
+	public QuadKey(F firstKey, S secondKey, T thirdKey, Long ownKey){
+		this.firstKey = firstKey;
+		this.secondKey = secondKey;
+		this.thirdKey = thirdKey;
+		this.ownKey = ownKey;
+	}
+	
+	/*
+	public boolean containsKey(Object key){
+		if(key != null){
+			if(key.equals(firstKey) || key.equals(secondKey) || key.equals(ownKey)){
+				return true;
+			}
+		}
+		return false;
+	}*/
+	
+
+	public boolean equalsFirstKey(Object key){
+		if(firstKey != null && key != null){
+			return firstKey.equals(key);
+		}else if(firstKey == null && key == null){
+			return true;
+		}
+		return false;
+	}
+	
+	public boolean equalsSecondKey(Object key){
+		if(secondKey != null && key != null){
+			return secondKey.equals(key);
+		}else if(secondKey == null && key == null){
+			return true;
+		}
+		return false;
+	}
+	
+	public boolean equalsThirdKey(Object key){
+		if(thirdKey != null && key != null){
+			return thirdKey.equals(key);
+		}else if(thirdKey == null && key == null){
+			return true;
+		}
+		return false;
+	}
+	
+	public boolean equalsOwnKey(Object key){
+		if(ownKey != null && key != null){
+			return ownKey.equals(key);
+		}else if(ownKey == null && key == null){
+			return true;
+		}
+		return false;
+	}
+	
+	public Object getFirstKey() {
+		return firstKey;
+	}
+
+	public void setFirstKey(F firstKey) {
+		this.firstKey = firstKey;
+	}
+
+	public Object getSecondKey() {
+		return secondKey;
+	}
+
+	public void setSecondKey(S secondKey) {
+		this.secondKey = secondKey;
+	}
+
+	public Object getOwnKey() {
+		return ownKey;
+	}
+
+	public void setOwnKey(Object ownKey) {
+		this.ownKey = ownKey;
+	}
+	
+	public Object getThirdKey() {
+		return thirdKey;
+	}
+
+	public void setThirdKey(T thirdKey) {
+		this.thirdKey = thirdKey;
+	}
+
+	@Override
+	public boolean equals(Object o){
+		if(o instanceof QuadKey){
+			QuadKey other = (QuadKey)o;
+			
+			if(this.equalsOwnKey(other.getOwnKey()) &&
+					this.equalsFirstKey(other.getFirstKey()) &&
+					this.equalsSecondKey(other.getSecondKey()) &&
+					this.equalsThirdKey(other.getThirdKey())){
+				return true;
+			}
+		}
+		return false;
+	}
+}