treats items property as a string

2019-08-28 04:13发布

问题:

I am trying to iterate over a collection of elements, which are complex types (another entities) using <c:forEach>:

<c:forEach items="#{repcatTree.items}" var="item">
    <div style="padding-top:7px; padding-bottom:7px; padding-right:15px;">
        <span class="report_item_category_class">
            <h:commandLink rendered="#{item.type == 'category'}" action="#{item.onNodeClicked}" styleClass="default_link">
                <h:graphicImage url="/views/tree/images/folder_big.gif" />
                <h:outputText value="#{item.attributes.FILE_NAME}" style="font-size:14px; font-weight:bold; padding-left:5px" />
            </h:commandLink>
            <h:commandLink rendered="#{item.type == 'report'}" styleClass="default_link" action="action_report_run" title="#{item.cells['report_name'].toolTip}">
                <h:graphicImage url="/icon?rdd_path=#{item.attributes.RDD_PATH}" />               
                <h:outputText value="#{item.cells['report_name'].display}" style="font-size:14px; font-weight:bold; padding-left:5px" />
                <f:param name="nodePath" value="#{item.attributes.RDD_PATH}" />
                <f:param name="nodePrettyPath" value="#{item.attributes.CAT_PATH}" />
            </h:commandLink>
        </span>
    </div>
</c:forEach>

However, inside of forEach block logic treats '#{item}' element as a regular java.lang.String causing

javax.el.PropertyNotFoundException: The class 'java.lang.String' does not have the property 'type'.

Here's my faces-config.xml (JSF 1.2) related mapping entry:

<managed-bean>
    <managed-bean-name>repcatTree</managed-bean-name>   
    <managed-bean-class>rpt.engine.runner.tree.impl.RepcatTreeModel</managed-bean-class>
    <managed-bean-scope>session</managed-bean-scope>
    <managed-property>
        <property-name>path</property-name>
        <property-class>java.lang.String</property-class>
        <value>/</value>
    </managed-property>
    <managed-property>
        <property-name>listener</property-name>
        <property-class>rpt.engine.runner.tree.listeners.ReportsTreeModelListener</property-class>
        <value>#{reportsTreeModelListener}</value>
    </managed-property>       
    <managed-property>
        <property-name>tableModel</property-name>
        <property-class>rpt.engine.runner.table.TableModel</property-class>
        <value>#{repcatTableModel}</value>
    </managed-property>
</managed-bean> 

How is this caused and how can I solve it?

回答1:

That can happen if you used the wrong JSTL version for the environment or used the wrong JSTL taglib URI declaration.

JSF 1.2 implies a minimum of Servlet 2.5 (your webapp's web.xml must also be declared as such!), which in turn implies a minimum of JSTL 1.2, which in turn implies a taglib URI of http://java.sun.com/jsp/jstl/core.

Make sure you got everything right. Your particular problem is caused because #{repcatTree.items} is not interpreted as an EL expression, but instead as plain string, indicating that EL in JSTL doesn't work at all, which in turn indicates that you're possibly using JSTL 1.0/1.1 (note that Glassfish already bundles JSTL, so you should not ship any along with your webapp), or used the JSTL 1.0 taglib URI without the /jsp path, or the web.xml is not declared conform Servlet 2.5.

See also:

  • Our JSTL wiki page - contains download links and installation instructions