finishe dall except parameterization

src/main/java/com/zipcodewilmington/generic/group/Group.java

@@ -3,6 +3,7 @@ package com.zipcodewilmington.generic.group;
 import com.zipcodewilmington.generic.identifiables.IdentifiableInterface;
 
 import java.io.Serializable;
+import java.lang.reflect.Type;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.function.Predicate;
@@ -12,7 +13,8 @@ import java.util.stream.Stream;
 /**
  * @author leon on 06/12/2018.
  */
-public class Group<TypeOfId, TypeOfEntity extends IdentifiableInterface> extends AbstractGroup{
+public class Group<TypeOfId extends Serializable,
+        TypeOfEntity extends IdentifiableInterface> extends AbstractGroup{
 
     List<TypeOfEntity> list = new ArrayList<>();
 
@@ -51,8 +53,8 @@ public class Group<TypeOfId, TypeOfEntity extends IdentifiableInterface> extends
     }
 
     @Override
-    public List filter(Predicate predicate) {
-        return (List) Stream.of(list).filter(predicate).collect(Collectors.toList());
+    public List<TypeOfEntity> filter(Predicate predicate) {
+        return (List<TypeOfEntity>) list.stream().filter(predicate).collect(Collectors.toList());
     }
 
     @Override