JSF轉換導致驗證器（S）被忽略

Question

這裏的領域：

<h:inputText id="mobilePhoneNo" 
      value="#{newPatientBean.phoneNo}" 
      required="true" 
      requiredMessage="Required" 
      validator="#{mobilePhoneNumberValidator}" 
      validatorMessage="Not valid (validator)" 
      converter="#{mobilePhoneNumberConverter}" 
      converterMessage="Not valid (converter)" 
      styleClass="newPatientFormField"/> 

而且驗證：

@Named 
@ApplicationScoped 
public class MobilePhoneNumberValidator implements Validator, Serializable 
{ 
    @Override 
    public void validate(FacesContext fc, UIComponent uic, Object o) throws ValidatorException 
    { 
     // This will appear in the log if/when this method is called. 
     System.out.println("mobilePhoneNumberValidator.validate()"); 

     UIInput in = (UIInput) uic; 
     String value = in.getSubmittedValue() != null ? in.getSubmittedValue().toString().replace("-", "").replace(" ", "") : ""; 

     if (!value.matches("04\\d{8}")) 
     { 
      throw new ValidatorException(new FacesMessage(FacesMessage.SEVERITY_ERROR, "Please enter a valid mobile phone number.", null)); 
     } 
    } 
} 

當我按表格中的命令按鈕，我得到了以下行爲：

• 當該字段爲空時，該消息是「無效（轉換器）」。
• 當該字段有一個有效的條目時，該消息是「無效（驗證器）」。
• 當該字段有無效的條目時，該消息爲「無效（轉換器）」。

在所有三種情況下，調用了MobilePhoneNumberConverter.getAsObject()。 MobilePhoneNumberValidator.validate()是從不調用。當該字段爲空時，它忽略required="true"屬性並直接轉換。

我還以爲正確的行爲應該是：

• 當該字段爲空，該消息應該是「必需的」。
• 當該字段有一個有效的條目時，應該根本沒有消息。
• 當該字段有無效的條目時，該消息應該是「無效（驗證器）」。
• 如果在某種程度上通過轉換得到的驗證沒有通過，則該消息應該是「無效（轉換器）」。

注意：支持bean是請求的範圍，所以沒有花哨的AJAX業務在這裏進行。

更新：

也許它有一些做與javax.faces.INTERPRET_EMPTY_STRING_SUBMITTED_VALUES_AS_NULL被設置爲true？

Answer 1

轉換髮生在驗證之前。當值爲null或空時，轉換器也會被調用。如果您想將null值委託給驗證器，那麼您需要設計您的轉換器，當提供的值爲null或空時，它只返回null。

@Override 
public Object getAsObject(FacesContext context, UIComponent component, String value) { 
    if (value == null || value.trim().isEmpty()) { 
     return null; 
    } 

    // ... 
} 

---

無關到具體的問題，你的驗證器有一個缺陷。您不應該從組件提取提交的值。它是而不是與轉換器返回的值相同。正確的提交和轉換值已經作爲第三方法參數。

@Override 
public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException { 
    if (value == null) { 
     return; // This should normally not be hit when required="true" is set. 
    } 

    String phoneNumber = (String) value; // You need to cast it to the same type as returned by Converter, if any. 

    if (!phoneNumber.matches("04\\d{8}")) { 
     throw new ValidatorException(new FacesMessage(FacesMessage.SEVERITY_ERROR, "Please enter a valid mobile phone number.", null)); 
    } 
} 

Answer 2

在閱讀BalusC的評論後，我再次更新此帖。

我創建了一個小型演示應用程序，查看階段以及何時進行轉換和驗證。

查看：

<h:form> 
    <h:inputText value="#{demoBean.field}"> 
     <f:converter converterId="demoConverter"/> 
     <f:validator validatorId="demoValidator"/> 
    </h:inputText> 
    <h:commandButton value="Submit" action="#{demoBean.demoAxn()}"/> 
</h:form> 

管理的bean：

@ManagedBean 
@SessionScoped 
public class DemoBean implements Serializable { 
    private String field; 

    public DemoBean() { 
     System.out.println(Thread.currentThread().getStackTrace()[1]); 
    } 

    public String getField() { 
     System.out.println(Thread.currentThread().getStackTrace()[1]); 
     return field; 
    } 

    public void setField(String field) { 
     System.out.println(Thread.currentThread().getStackTrace()[1]); 
     this.field = field; 
    } 

    public String demoAxn() { 
     System.out.println(Thread.currentThread().getStackTrace()[1]); 
     return null; 
    } 
} 

轉換器：

@FacesConverter(value="demoConverter") 
public class DemoConverter implements Converter { 

    @Override 
    public Object getAsObject(FacesContext context, UIComponent component, String value) { 
     System.out.println(Thread.currentThread().getStackTrace()[1]);    
     return value; 
    } 

    @Override 
    public String getAsString(FacesContext context, UIComponent component, Object value) { 
     System.out.println(Thread.currentThread().getStackTrace()[1]); 
     return (String) value; 
    }  
} 

驗證：

@FacesValidator(value="demoValidator") 
public class DemoValidator implements Validator { 

    @Override 
    public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException { 
     System.out.println(Thread.currentThread().getStackTrace()[1]); 
    } 

} 

階段監聽器：

public class DemoPhaseListener implements PhaseListener { 
    @Override 
    public void afterPhase(PhaseEvent event) { 
     System.out.println(Thread.currentThread().getStackTrace()[1]); 
     System.out.println("PhaseId: " + event.getPhaseId() + " ===============================\n\n");   
    } 

    @Override 
    public void beforePhase(PhaseEvent event) { 
     System.out.println("\n\nPhaseId: " + event.getPhaseId() + " ==============================="); 
     System.out.println(Thread.currentThread().getStackTrace()[1]);   
    } 

    @Override 
    public PhaseId getPhaseId() { 
     return PhaseId.ANY_PHASE; 
    }  
} 

註冊階段監聽器：

<lifecycle> 
    <phase-listener>pkg.DemoPhaseListener</phase-listener> 
</lifecycle> 

通過該設置時 「提交」 按鈕時，輸出爲：

 
INFO: PhaseId: RESTORE_VIEW 1 =============================== 
INFO: pkg.DemoPhaseListener.beforePhase(DemoPhaseListener.java:17) 
INFO: pkg.DemoPhaseListener.afterPhase(DemoPhaseListener.java:10) 
INFO: PhaseId: RESTORE_VIEW 1 =============================== 

INFO: PhaseId: APPLY_REQUEST_VALUES 2 =============================== 
INFO: pkg.DemoPhaseListener.beforePhase(DemoPhaseListener.java:17) 
INFO: pkg.DemoPhaseListener.afterPhase(DemoPhaseListener.java:10) 
INFO: PhaseId: APPLY_REQUEST_VALUES 2 =============================== 

INFO: PhaseId: PROCESS_VALIDATIONS 3 =============================== 
INFO: pkg.DemoPhaseListener.beforePhase(DemoPhaseListener.java:17) 
INFO: pkg.DemoConverter.getAsObject(DemoConverter.java:13) 
INFO: pkg.DemoValidator.validate(DemoValidator.java:14) 
INFO: pkg.DemoBean.getField(DemoBean.java:17) 
INFO: pkg.DemoPhaseListener.afterPhase(DemoPhaseListener.java:10) 
INFO: PhaseId: PROCESS_VALIDATIONS 3 =============================== 

INFO: PhaseId: UPDATE_MODEL_VALUES 4 =============================== 
INFO: pkg.DemoPhaseListener.beforePhase(DemoPhaseListener.java:17) 
INFO: pkg.DemoBean.setField(DemoBean.java:22) 
INFO: pkg.DemoPhaseListener.afterPhase(DemoPhaseListener.java:10) 
INFO: PhaseId: UPDATE_MODEL_VALUES 4 =============================== 

INFO: PhaseId: INVOKE_APPLICATION 5 =============================== 
INFO: pkg.DemoPhaseListener.beforePhase(DemoPhaseListener.java:17) 
INFO: pkg.DemoBean.demoAxn(DemoBean.java:27) 
INFO: pkg.DemoPhaseListener.afterPhase(DemoPhaseListener.java:10) 
INFO: PhaseId: INVOKE_APPLICATION 5 =============================== 

INFO: PhaseId: RENDER_RESPONSE 6 =============================== 
INFO: pkg.DemoPhaseListener.beforePhase(DemoPhaseListener.java:17) 
INFO: pkg.DemoBean.getField(DemoBean.java:17) 
INFO: pkg.DemoConverter.getAsString(DemoConverter.java:20) 
INFO: pkg.DemoPhaseListener.afterPhase(DemoPhaseListener.java:10) 
INFO: PhaseId: RENDER_RESPONSE 6 =============================== 

但是，當做出改變在轉換器中拋出NPE如下：

@Override 
public Object getAsObject(FacesContext context, UIComponent component, String value) { 
    System.out.println(Thread.currentThread().getStackTrace()[1]);    
    throw new NullPointerException(); 
} 

輸出爲：

 
INFO: PhaseId: RESTORE_VIEW 1 =============================== 
INFO: pkg.DemoPhaseListener.beforePhase(DemoPhaseListener.java:17) 
INFO: pkg.DemoPhaseListener.afterPhase(DemoPhaseListener.java:10) 
INFO: PhaseId: RESTORE_VIEW 1 =============================== 

INFO: PhaseId: APPLY_REQUEST_VALUES 2 =============================== 
INFO: pkg.DemoPhaseListener.beforePhase(DemoPhaseListener.java:17) 
INFO: pkg.DemoPhaseListener.afterPhase(DemoPhaseListener.java:10) 
INFO: PhaseId: APPLY_REQUEST_VALUES 2 =============================== 

INFO: PhaseId: PROCESS_VALIDATIONS 3 =============================== 
INFO: pkg.DemoPhaseListener.beforePhase(DemoPhaseListener.java:17) 
INFO: pkg.DemoConverter.getAsObject(DemoConverter.java:13) 
INFO: pkg.DemoPhaseListener.afterPhase(DemoPhaseListener.java:10) 
INFO: PhaseId: PROCESS_VALIDATIONS 3 =============================== 

INFO: pkg.DemoBean.getField(DemoBean.java:17) 

但堆棧跟蹤被顯示在所得到的圖。