JSF SelectOneMenu 在另一个字段上的验证错误已修复并重新提交表单后显示错误值

JSF SelectOneMenu showing wrong value after validation error on another field was fixed and form re-submitted

我 运行 遇到一个非常奇怪的问题,即 selectOneMenu jsf 控件在出现验证错误后将错误值显示为所选值(即使模型已更新为正确值)之前(不是当前)提交的完全不同的字段。

如何复制(最低代码如下):

  1. 加载表单并将 "Required text field" 文本框留空。
  2. 在几个下拉列表中将一些值设置为活动和非活动 以下。
  3. 提交表格。将出现有关的错误消息 "Required text field" 为空,您设置的下拉菜单将 仍然具有您给他们的相同价值(预期)。的打印输出 模型所具有的仍将显示旧值而不是值 您选择(预期)。
  4. 将一些文字放入“必填文字” 字段”并提交表单。
  5. 错误消息消失并且 表格得到 "saved"。模型旁边的打印输出 下拉菜单具有您设置的值(预期),但是,下拉菜单 自己不再有你选择的值作为选择 选项(未预期)。

示例代码:

    <?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:h="http://xmlns.jcp.org/jsf/html"
      xmlns:ui="http://xmlns.jcp.org/jsf/facelets"
      xmlns:f="http://xmlns.jcp.org/jsf/core">
    <h:head>
        <title>Facelet Title</title>
    </h:head>
    <h:body>
        <h:form id="myForm">
            <div>
                <h:outputLabel value="Required text field" for="reqField" />
                <h:inputText value="#{myBeanController.requiredField}" id="reqField" label="Required Text Field" required="true" />
            </div>
            <div>
                <h:outputLabel value="some objects" />
                <ui:repeat value="#{myBeanController.bunchOfObjects}" var="obj">
                    <div>
                        value on obj model: #{obj}
                        <h:selectOneMenu value="#{obj.type}">
                            <f:selectItems value="#{myBeanController.availableRequiredTypeOptions}" />
                        </h:selectOneMenu>
                    </div>
                </ui:repeat>
            </div>
            <div>
                <h:commandButton value="Submit" action="#{myBeanController.save}" />
            </div>
        </h:form>
    </h:body>
</html>

控制器 bean:

package com.mycompany.reproducefieldnotsavingaftervalidation;

import java.util.Collection;
import java.util.LinkedList;
import java.util.Map;
import java.util.TreeMap;
import javax.annotation.PostConstruct;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
import org.apache.commons.lang3.text.WordUtils;

@ManagedBean
@SessionScoped
public class MyBeanController {
    private String requiredField;
    private Collection<MyDomainClass> bunchOfObjects;

    @PostConstruct
    public void init(){
        // create some sample objects
        bunchOfObjects = new LinkedList<>();
        bunchOfObjects.add(new MyDomainClass(MyDomainClass.PossibleTypes.ACTIVE));
        bunchOfObjects.add(new MyDomainClass(MyDomainClass.PossibleTypes.INACTIVE));
        bunchOfObjects.add(new MyDomainClass(MyDomainClass.PossibleTypes.UNKNOWN));
        bunchOfObjects.add(new MyDomainClass(MyDomainClass.PossibleTypes.UNKNOWN));
        bunchOfObjects.add(new MyDomainClass(MyDomainClass.PossibleTypes.UNKNOWN));
        bunchOfObjects.add(new MyDomainClass(MyDomainClass.PossibleTypes.UNKNOWN));
    }

    public void save() {
        System.out.println("SAVING FORM");
        System.out.println("requiredField: " + getRequiredField());
        System.out.println("Bunch of objects: ");
        for(MyDomainClass obj : getBunchOfObjects()) {
            System.out.println("/tObj: " + obj);
        }
    }

    public Map<String, String> getAvailableRequiredTypeOptions() {
        Map<String, String> options = new TreeMap<>();

        for(MyDomainClass.PossibleTypes type : MyDomainClass.PossibleTypes.values()) {
            // make the text of the option pretty by removing all caps and replacing underscores with space
            options.put(WordUtils.capitalizeFully(type.name(), new char[]{'_'}).replaceAll("_", " "), type.name());
        }

        return options;
    }

    public String getRequiredField() {
        return requiredField;
    }

    public void setRequiredField(String requiredField) {
        this.requiredField = requiredField;
    }

    public Collection<MyDomainClass> getBunchOfObjects() {
        return bunchOfObjects;
    }

    public void setBunchOfObjects(Collection<MyDomainClass> bunchOfObjects) {
        this.bunchOfObjects = bunchOfObjects;
    }    
}

型号:

package com.mycompany.reproducefieldnotsavingaftervalidation;

import java.util.Objects;

public class MyDomainClass {
    private String type;

    public MyDomainClass() { }

    public MyDomainClass(PossibleTypes type) {
        this.type = type.name();
    }

    public MyDomainClass(String type) {
        this.type = type;
    }

    public static enum PossibleTypes {
        UNKNOWN, ACTIVE, INACTIVE
    }

    public String getType() {
        return type;
    }

    public void setType(String type) {
        this.type = type;
    }

    @Override
    public String toString() {
        return "MyDomainClass{" + "type=" + type + '}';
    }

    @Override
    public int hashCode() {
        int hash = 7;
        hash = 79 * hash + Objects.hashCode(this.getType());
        return hash;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (!(obj instanceof MyDomainClass)) {
            return false;
        }
        final MyDomainClass other = (MyDomainClass) obj;
        if (!Objects.equals(this.getType(), other.getType())) {
            return false;
        }
        return true;
    }

}

切换

<ui:repeat> 

<c:forEach>

问题似乎已解决。我不知道为什么 ui:repeat 只在先前验证失败后的保存中导致问题,而不是在第一次有效保存时导致问题(如果有人知道这个问题的答案,请 post 它,我会有兴趣知道)。根据一些研究,ui:repeat 发生在与 f:selectItem 或 f:selectItem 不同的阶段,但我希望每次保存时都会发生此问题,但事实并非如此。

无论如何,如果您看到类似的东西并且您的选择在 ui:repeat 内,请尝试将其切换为 c:forEach 以查看是否可以解决问题。