Question

我是struts2的新手，我在提交表单和使用验证时遇到错误。

请参阅我的struts.xml

<action name="alltagpage" class="com.ksh.tags.Initialization">
            <result name="success">/alltagspage.jsp</result>
        </action>
        <action name="submittags" class="com.ksh.tags.TagActionClass">
            <result name="input">/alltagspage.jsp</result>
            <result name="success">/tagsresult.jsp</result>
        </action>

当我传递此alltagpage请求时，它正在初始化“Initialization”类并初始化radiobutton的内容。

public class Initialization {

    private List<String> languages;
    private List<KeyValue> genders;

    public Initialization()
    {
        System.out.println("Model COnstructor is called");

        languages = new ArrayList<String>();
        languages.add("English");
        languages.add("Hindi");
        languages.add("Gujarati");

        KeyValue keyValue0 = new KeyValue();
        keyValue0.setKey(0);
        keyValue0.setValue("Male");

        KeyValue keyValue1 = new KeyValue();
        keyValue1.setKey(1);
        keyValue1.setValue("Female");

        KeyValue keyValue2 = new KeyValue();
        keyValue2.setKey(2);
        keyValue2.setValue("Unknown");

        genders = new ArrayList<KeyValue>();
        genders.add(keyValue0);
        genders.add(keyValue1);
        genders.add(keyValue2);
    }
    getters and setters..

    public String execute()
    {
        return "success";
    }
}

以下是我提交表格时会打电话的课程。

public class TagActionClass extends ActionSupport implements ModelDriven<Model> {

    Initialization initialization = new Initialization();
    Model model = new Model();

    public String execute()
    {
        return "success";
    }

    @Override
    public Model getModel() 
    {
        return model;
    } 


    public void validate()
    {
        System.out.println("Kshitij :"+ getModel().getTextfield());

        System.out.println("Kshitij :"+ getModel().getSelectedlanguage());

        System.out.println("Kshitij :"+ getModel().getSelectedgender());

        if(getModel().getTextfield() == null || getModel().getTextfield().isEmpty())
        {
            addActionError("Text Field is empty");
        }
    }
}

当我使用空用户名提交表单时，它会触发错误。我知道为什么会这样。我需要解决方案。

org.apache.jasper.JasperException: tag 'radio', field 'list', name 'selectedlanguage': The requested list key 'languages' could not be resolved as a collection/array/map/enumeration/iterator type. Example: people or people.{name} - [unknown location]
    org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:534)
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:457)
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:333)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
    org.apache.struts2.dispatcher.ServletDispatcherResult.doExecute(ServletDispatcherResult.java:159)
    org.apache.struts2.dispatcher.StrutsResultSupport.execute(StrutsResultSupport.java:186)
    com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:373)
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:277)
    com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:263)
    org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
    com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
    com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:133)
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
    com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:207)
    com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
    com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:207)
    com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
    com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:190)
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
    org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
    org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94)
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
    org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:243)
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
    com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100)
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

Answer 1

在我看来，这是struts2验证中第一个也是最常见的问题。

当验证失败时，struts2会重定向到您的“输入”结果（在“struts.xml”中定义），并且它不会执行您的任何操作方法。如果输入是JSP，它将尝试呈现该JSP ... 你没有包含yor JSP，但它可能包含radio，select或其他标签，它们希望从你的动作中收集一个集合来初始化它们，但是当验证失败时它们不会得到任何东西，所以这就是错误。

解决方案：您需要在操作中使用一些方法来创建jsp中始终需要的所需集合或其他参数。您可以在您的动作构造函数中执行此操作，即使验证失败，也会调用它，但这是一个肮脏的解决方案。好的解决方案是使用Preparable拦截器（包含在Struts2拦截器的DefaultStack中）。然后，即使验证失败，您也将拥有一个始终被调用的prepare（）方法。

http://struts.apache.org/release/2.0.x/docs/prepare-interceptor.html

当我使用无线电，选择等时，Struts2验证失败

1 个答案: