我看过其他问题this https://stackoverflow.com/questions/17774367/selectonemenu-converter and this https://stackoverflow.com/questions/16164237/primefaces-selectonemenu-with-converter-not-working-with-my-backingbean, etc, 问题是我的转换被调用但 selectOneMenu 的值没有改变。我的实体类已生成,并且具有 equals 和 hashCode,我不想更改其中的任何内容 - 如果重新生成它,则所有更改都将丢失(解决方法是更改实体类的 toString)。
HTML 代码片段:
<p:selectOneMenu id="defid"
value="#{abcController.selected.defid}"
converter="defConverter">
转换器:
@FacesConverter("defConverter")
public class DefConverter implements Converter
{
private static final Logger LOG = Logger.getLogger(DefConverter.class.getName());
@EJB
private DefFacade defFacade;
@Override
public Object getAsObject(FacesContext fc, UIComponent uic, String string)
{
LOG.info("getAsObject: " + string);
try
{
return defFacade.findWithNFieldsWithValue("name", string, "=").get(0);
}
catch (Exception ex)
{
LOG.log(Level.SEVERE, "Error while fetching Def for " + string, ex);
}
return null;
}
@Override
public String getAsString(FacesContext fc, UIComponent uic, Object obj)
{
LOG.info("getAsString obj class: " + obj.getClass().getName());
if(obj instanceof Def)
{
Def def = (Def)obj;
LOG.info("getAsString def name: " + def.getName());
return def.getName();
}
else
{
StringBuilder sbError = new StringBuilder("The object of class ");
sbError.append(obj.getClass().getName()).append(" is not of Def");
throw new ClassCastException(sbError.toString());
}
}
}
实体类被剪断(这是生成的):
...
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name = "defid")
private Long defid;
...
@Override
public int hashCode()
{
int hash = 0;
hash += (defid != null ? defid.hashCode() : 0);
return hash;
}
@Override
public boolean equals(Object object)
{
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof Def))
{
return false;
}
Def other = (Def) object;
if ((this.defid == null && other.defid != null) || (this.defid != null && !this.defid.equals(other.defid)))
{
return false;
}
return true;
}
当页面加载时,我可以看到日志语句如下:
getAsString obj class: com.xyz.Def
getAsString def name: Name 1
getAsString obj class: com.xyz.Def
getAsString def name: Name 2
getAsString obj class: com.xyz.Def
getAsString def name: Name 3
因此,转换器被调用并返回正确的值,但在页面上它仍然是com.xyz.Def[defid=1](下拉并正常)