org.primefaces.component.datatable.DataTable 不能转换为 MyEntity

Question

我正在试验 DataTable - 单元格编辑，如 PrimeFaces showcase 所示，我想保存修改后的对象 方法onCellEdit定义如下：

public void onCellEdit(CellEditEvent event) {  
       Object oldValue = event.getOldValue();  
       Object newValue = event.getNewValue();
       Matpilotaccess mpltiacc = (Matpilotaccess)event.getSource();
       articleDAO.Updatetable(mpltiacc);
       //event.getSource();
       System.out.println("///////////////////////"+event.getOldValue());
       System.out.println("///////////////////////"+event.getNewValue());
}

Matpilotaccess 类定义如下：

@Entity
@Table(name="matpilotaccess")
public class Matpilotaccess implements Serializable{

    private static final long serialVersionUID = 1L;

    @Id
    @Column(name="idmatpilotaccess1")
    private int idmatpilotaccess1;
    @Column(name="serie")
    private String serie;
    @Column(name="cap")
    private int cap;
    @Column(name="cal")
    private String cal;
    @Column(name="classe")
    private int classe;
    @Column(name="unite")
    private String unite;
    @Column(name="puhtva")
    private float puhtva;

    @Column(name="puttc")
    private float puttc;
    @Column(name="quantite")
    private float quantite;
    @Column(name="monthtva")
    private float monthtva;
    @Column(name="montttc")
    private float montttc;


    public Matpilotaccess1(int idmatpilotaccess1, String serie, int cap,
            String cal, int classe, String unite, float puhtva, float puttc,
            float quantite, float monthtva, float montttc) {
        super();
        this.idmatpilotaccess1 = idmatpilotaccess1;
        this.serie = serie;
        this.cap = cap;
        this.cal = cal;
        this.classe = classe;
        this.unite = unite;
        this.puhtva = puhtva;
        this.puttc = puttc;
        this.quantite = quantite;
        this.monthtva = monthtva;
        this.montttc = montttc;
    }
    public Matpilotaccess1() {
        super();
    }

    //getters and setters



}

并抛出以下异常：

org.primefaces.component.datatable.DataTable cannot be cast to com.pfe.model.Matpilotaccess

如何继续将 primefacesDatatable 转换为 Matpilotaccess（我的实体）？

Answer 1

“用修改后的对象替换旧对象”意味着更新一个实体对象而不是更新整个实体（数据表），所以这应该足够了：

public void onCellEdit(CellEditEvent event) {  
    ...
    FacesContext context = FacesContext.getCurrentInstance();
    Matpilotaccess mpltiacc  = context.getApplication().evaluateExpressionGet(context, "#{mpltiacc}", Matpilotaccess.class);  
    articleDAO.Updatetable(mpltiacc);
    ...
}