Connect between category and subcategory in jsf

[Rapter1990]

I devised a sample category with subcategory module in jsf by eclipse. I made an adding category module without any issue but I couldn't make an adding subcategory under related category . How I can devise addSubcategory() function in SubCategory which is my issue.. Here the code below.

Suncategory .xhtml

<h:form>

<p:panelGrid columns="2">

    <h:outputLabel value="Category Name></h:outputLabel>

    <p:selectOneMenu value="#{subCategoryMB.categoryName}">
        <f:selectItem itemLabel="Select Category" itemValue=""></f:selectItem>
        <f:selectItems value="#{subCategoryMB.categorylist}" />
    </p:selectOneMenu>

    <h:outputLabel value="Category Name"></h:outputLabel>
    <p:inputText value="#{subCategoryMB.subcategory.subName}"></p:inputText>

    <h:outputLabel value="Category Description"></h:outputLabel>
    <p:inputText value="#{subCategoryMB.subcategory.subNameDes}"></p:inputText>

    <h:commandButton value="Add Subcategory" action="#{subCategoryMB.addSubCategory()}"></h:commandButton>


</p:panelGrid>

/h:form
</h:body

Category Dao

public List getAllcategoriesbyName(String name) {
// TODO Auto-generated method stub
Session session = HibernateUtil.getSessionFactory().openSession();

try {

    List<Category> liste = session.createQuery("SELECT c FROM Category C where lower(name)='"+name+"'").list();
    liste.toString();
    return liste;


} catch (Exception e) {
    e.printStackTrace();

}finally {

    session.close();

}
return null;

}
SubCategoryMB

public class SubCategoryMB {

SubCategory subcategory = new SubCategory();

private String categoryName;
private List categorylist;
private List subCategoryList;
private Category category= new Category();

public SubCategoryMB() {
// TODO Auto-generated constructor stub
}

public SubCategory getSubcategory() {
return subcategory;
}

public void setSubcategory(SubCategory subcategory) {
this.subcategory = subcategory;
}

public List getCategorylist() {
CategoryDAO cDao = new CategoryDAO();
this.categorylist= cDao.getAllcategoriesSelectItemName();
return categorylist;
}

public void setCategorylist(List categorylist) {
this.categorylist = categorylist;
}

public String getCategoryName() {
return categoryName;
}

public void setCategoryName(String categoryName) {
this.categoryName = categoryName;
}

public Category getCategory() {
return category;
}

public void setCategory(Category category) {
this.category = category;
}

public List getSubCategoryList() {
SubCategoryDAO subDao = new SubCategoryDAO();
this.subCategoryList= subDao.getAllSubcategories();
return subCategoryList;
}

public void addSubCategory(){

       // ISSUE
categorylist= new CategoryDAO().getAllcategoriesbyName(categoryName);
System.out.println(categorylist.get(0));
//category.setId(categorylist.get(0).getId());  
//subcategory.setCategory(category);
//subcategory.setSubName(subcategory.getSubName());
//subcategory.setSubNameDes(subcategory.getSubNameDes());
//new SubCategoryDAO().addSubCategory(subcategory);

}
}