TEntityTableA
   @Id
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 36)
    @Column(name = "Table_A_ID")
    private String table_A_ID;

  @OneToMany(mappedBy = "table_A_ID")
    private Collection<TEntityTableB> tEntityTableBCollection;
-----------------------------------------------------------------------------
TEntityTableB
    @Id   
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 36)
    @Column(name = "Table_B_ID")
    private String table_B_ID;

@JoinColumn(name = "Table_A_ID", referencedColumnName = "Table_A_ID")
@ManyToOne 
private  TEntityTableA table_A_ID;

@OneToMany(mappedBy = "table_B_ID")
    private Collection<TEntityTableB> tEntityTableCCollection;
------------------------------------------------------------------------------------------
TEntityTableC
    @Id
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 36)
    @Column(name = "Table_C_ID")
    private String  table_B_ID;
    @Size(max = 25)
    @Column(name = "Cell")
    private String cell;
    @JoinColumn  (name = "Table_B_ID", referencedColumnName = "Table_B_ID")
    @ManyToOne 
    private TEntityTableB table_B_ID;

// Entities-Injection fort 3 Tables

@EJB  
     TableB_Bean_IF TableB_Bean;
@EJB  
     TableA_Bean_IF TableA_Bean;
@EJB  
     TableC_Bean_IF TableC_Bean;
//---------------------------------------------------------------------

//INSERT

//create Record in Table B with selected PK from Table A : Table A is master for Table B
// Create Record in Table C with selected PK from Table B : Table B is Master for Table A

container_Table_A = new BeanItemContainer<TEntityTableA>(TEntityTableA.class, getallRecordsTableA)   //container for all records from Table A
Item_Table_A = containerTableA.getItem(event.getItemId());  // Current Item from Table A from Click-Event 

    TEntityTableB Insert_NewRec_Table_B = new TEntityTableB();    //prepearing Insert for Table B         
    Insert_NewRec_Table_B.set_TableA_ID(ItemTableA.getBean());   //   Primary Key from Table A to Table B  as FK
    TableB_Bean.create(Insert_NewRec_Table_B);                  //Insert to Talbe B 
    Item_Table_A.getBean().get_RecodsCollection_for_Table_B().add(Insert_NewRec_Table_B);  //Inserted Item to collection of Records from Table B in Table A


//for (TKeywordsTable key : getallkeys) {   //some loop for insert

            TEntityTableC Insert_NewRec_Table_C = new TEntityTableC();      //prepearing Insert for Table B 

            Insert_NewRec_Table_C.set_TableB_ID(Insert_NewRec_Table_B);    //   Primary Key from Table A to Table B as FK
            Insert_NewRec_Table_B.get_RecordsCollection_for_Table_C().add(Insert_NewRec_Table_C);  //Inserted Item to collection of Records from Table C in Table B
            TableC_Bean.create(Insert_NewRec_Table_C);   //Insert to Talbe C 

             TableC_Bean.flush();
             TableB_Bean.flush();
//             TableA_Bean.flush();         
             
//    }

//----------------------------------------------------------------------------------------------
//DELETE: 

try {
    
            if (Item_Table_A != null){
             for ( TEntityTableB condit : Item_Table_A.getBean().get_RecordsCollection_for_Table_B()){

               for (TEntityTableC kw : condit.get_RecordsCollection_for_Table_C()) {
               TableC_Bean.remove(kw);
               }
             TableC_Bean.getCollection_for_Table_C().clear();
            TableB_Bean.remove(condit);
          }             
        }