Integrated the clusters in a simple way

java/com.sap.sse.datamining.shared/src/com/sap/sse/datamining/shared/SSEDataMiningSerializationDummy.java

@@ -3,12 +3,14 @@ package com.sap.sse.datamining.shared;
 import java.io.Serializable;
 
 import com.sap.sse.datamining.shared.impl.GenericGroupKey;
+import com.sap.sse.datamining.shared.impl.dto.ClusterDTO;
 
 @SuppressWarnings("unused")
 public final class SSEDataMiningSerializationDummy implements Serializable {
     private static final long serialVersionUID = 1L;
     
     private GenericGroupKey<String> groupKey;
+    private ClusterDTO cluster;
     
     private SSEDataMiningSerializationDummy() { }
     

java/com.sap.sse.datamining.shared/src/com/sap/sse/datamining/shared/impl/dto/ClusterDTO.java

@@ -0,0 +1,54 @@
+package com.sap.sse.datamining.shared.impl.dto;
+
+import java.io.Serializable;
+
+public class ClusterDTO implements Serializable {
+    private static final long serialVersionUID = -2962035066215989018L;
+    
+    private String signifier;
+
+    /**
+     * <b>Constructor for the GWT-Serialization. Don't use this!</b>
+     */
+    @Deprecated
+    ClusterDTO() { }
+
+    public ClusterDTO(String signifier) {
+        this.signifier = signifier;
+    }
+    
+    public String getSignifier() {
+        return signifier;
+    }
+    
+    @Override
+    public String toString() {
+        return getSignifier();
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + ((signifier == null) ? 0 : signifier.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        ClusterDTO other = (ClusterDTO) obj;
+        if (signifier == null) {
+            if (other.signifier != null)
+                return false;
+        } else if (!signifier.equals(other.signifier))
+            return false;
+        return true;
+    }
+    
+}